A phylogeny of Astyanax (Characiformes: Characidae) in ... - Ecosur

Zootaxa 4109 (2): 101–130 http://www.mapress.com/j/zt/ Copyright © 2016 Magnolia Press

Article

ISSN 1175-5326 (print edition)

ZOOTAXA

ISSN 1175-5334 (online edition)

http://doi.org/10.11646/zootaxa.4109.2.1 http://zoobank.org/urn:lsid:zoobank.org:pub:A084F919-17D2-41E1-90EB-0B6AF576C272

A phylogeny of Astyanax (Characiformes: Characidae) in Central and North America JUAN J. SCHMITTER-SOTO El Colegio de la Frontera Sur (ECOSUR), A.P. 424, MX-77000 Chetumal, QR, Mexico. E-mail: [email protected]

Abstract A phylogeny is presented for 34 species of Astyanax, 27 of them once included within A. aeneus or A. fasciatus in Central America and Mexico, based on 52 morphological characters (mostly osteological, but also pigmentation and meristics), with three outgroups. Monophyly is not supported for A. aeneus s. lat., as Brazilian species such as A. fasciatus s. str. and others occur also within that clade. There were only five resolved clades, three of them including both Brazilian and Central American species, one purely Nicaraguan, and one for central-northern Mexico and Texas. Coincidence with previous cladistic hypotheses is only partial. The genus Bramocharax Gill is not recovered, and thus confirmed as a synonym of Astyanax Baird & Girard. The findings point at a more complex biogeographic history of the region than usually recognized. Key words: Osteology, cladistics, Bramocharax, characids, tetragonopterines, Middle America

Resumen Se presenta una filogenia para 34 especies de Astyanax, 27 de ellas incluidas alguna vez en A. aeneus o A. fasciatus en Centroamérica y México, con base en 52 caracteres morfológicos (sobre todo osteológicos, pero también de pigmentación y merística), con tres grupos externos. No se apoya la monofilia de A. aeneus s. lat., dado que especies brasileñas, como A. fasciatus s. str. y otras, aparecen dentro de tal clado. Hubo sólo cinco clados definidos, tres de ellos con especies de Brasil y de Centroamérica, uno puramente nicaragüense, y uno del centro-norte de México y Texas; la coincidencia con hipótesis cladísticas previas es sólo parcial. El género Bramocharax Gill no se recupera, de modo que se confirma como sinónimo de Astyanax Baird & Girard. Según los hallazgos, la historia biogeográfica de la región es más compleja de lo que se generalmente se reconoce.

Introduction Few authors have attempted to provide a cladistic hypothesis for Central American and Mexican Astyanax, perhaps because the alpha taxonomy is not clear to begin with. The prevailing views have been that virtually all Astyanax forms in the study area belong either to A. fasciatus s. lat. (restricted to Rio São Francisco, Brazil, by Melo 2005), to A. aeneus s. lat. and, in northern Mexico and Petén (Miller et al. 2009), to A. mexicanus. Populations identifiable as Astyanax aeneus sensu lato (sometimes as A. fasciatus s. lat. or A. mexicanus s. lat.) in Central America and Mexico were molecularly analyzed by Ornelas-García et al. (2008), who recommended several species to be recognized. This suggestion is being examined by Schmitter-Soto (unpubl. data), who describes nine new species and resurrects nine more. The present contribution is a phylogenetic study of these species. Valdez-Moreno (1997) used 30 cranial characters for 23 Mexican populations and found osteological synapomorphies for the northern Mexican populations that validated their earlier recognition (e.g. Miller 1986) as A. mexicanus (de Filippi 1853), but she was unable to diagnose the southern Mexican – northern Middle American

Accepted by M.R. de Carvalho: 29 Feb. 2016; published: 6 May 2016

101

populations, provisionally called A. aeneus (Günther 1860, non Hensel 1870) by recent authors (e.g. Greenfield & Thomerson 1997; Bussing 1998; Schmitter-Soto et al. 2008; Miller et al. 2009). She also suggested that the population at Tamazulapan was a new species. Later on, Valdez-Moreno (2005) erected a phylogeny of 19 characid species, among which only two Astyanax, A. bimaculatus and A. mexicanus, and found the genus Bramocharax to be monophyletic, a finding contested by Ornelas-García et al. (2008) and by the present work. The results of Strecker et al. (2004) support Valdez-Moreno’s (1997), inasmuch as they found only one mtDNA lineage in northern Mexico, but at least five in the south. On the other hand, in their molecular cladogram for 147 populations, Ornelas-García et al. (2008) found two lineages in northern Mexico and several in Middle America, many of these considered as possible new species. As stated by Hausdorf et al. (2011), “…further investigations are necessary to show which […] clades classified by Ornelas-García et al. (2008) as separate species represent independently evolving entities.” However, Hausdorf et al. (2011) found only one slightly mixed population of A. mexicanus, with 4% individuals having nuclear genes from A. aeneus s. lat. Mirande (2010) included one Central American species of Bramocharax and one North American species of Astyanax in his osteology-based phylogenetic hypothesis of the Characidae. He found them to lie in quite distant clades, contradicting all previous work. The present phylogenetic reconstruction does not recover monophyly of A. aeneus s. lat. However, autapomorphies support the diagnosis of several new and resurrected species (Schmitter-Soto, unpubl. data) and the phylogeny, although not completely resolved, suggests an interesting, complex biogeographic history of the region, given the tendency for South American forms to be nested within Middle American clades. The objective of this contribution is to propose a phylogeny for the former species complex of A. aeneus s. lat. and close species in the same genus in Characidae, based on morphology (mostly osteology), and to compare it to other hypotheses, especially the molecular phylogeny by Ornelas-García et al. (2008) and the cladogram for Mexican populations based on cranial osteology by Valdez-Moreno (1997). All species of genus Bramocharax are included, as this taxon has been proven to be polyphyletic (Ornelas-García et al. 2008).

Material and methods The specimens examined (Appendix 1) include representatives from all nominal species that have at various times been synonymized with Astyanax aeneus s. lat. (Schmitter-Soto, unpubl. data), as well as comparative material of other species in the genus and all species of Bramocharax. Brycon guatemalensis, Hyphessobrycon compressus, and Roeboides guatemalensis were chosen as outgroups, following previous authors (Valdez-Moreno 1997, 2005; Ornelas-García et al. 2008), in addition to three species of Astyanax never determined as A. fasciatus s. lat.: A. bimaculatus, A. atratoensis, and A. orthodus All specimens were observed by the author, except for H. compressus and R. guatemalensis, coded based on the detailed illustrations by Valdez-Moreno (2005). Osteological methodology (i.e., clearing and staining) followed Taylor and van Dyke (1985), with the following minor modifications (W. Fink, pers. comm.): before dehydration, specimens were bleached in 50% H2O2 for ca. 3 h; after alcian blue staining and neutralization in a saturated borax solution, clearing proceeded by changing the enzyme buffer solution (30% borax solution, with trypsin) every 3 days, with the specimen over a neon-light box, then staining with alizarin red, returning to the clearing regime, rinsing, and equilibrating in glycerin. Radiographs (of type specimens) and skeletonized material were also used. Cladistic analyses were based on maximum parsimony and reconstructions were performed with program PARS-discrete character parsimony in package PHYLIP, version 3.69 (Felsenstein 2009); character states were considered as unordered, multistate, or binary, and all received the same weight. Meristic characters were used only if satisfactorily amenable to statistical coding: their states were determined by means of an ANOVA followed by a Duncan a posteriori test (“homogeneous subset coding”, Simon 1983), with differences significant at α < 0.05 marking different character states. The strict consensus tree was obtained and optimized using the package Mesquite, version 2.75 (Maddison & Maddison 2011), to arrive at a phylogenetic hypothesis. Optimization followed the ACCTRAN option in order not to lose any putative synapomorphy (Kitching et al. 1998). Homoplasy levels were calculated with Mesquite, as consistency and retention indices, for the tree (CI, RI) and also for every character (ci, ri) (Archie 1989, Farris 1989).

102 · Zootaxa 4109 (2) © 2016 Magnolia Press

SCHMITTER-SOTO

Results Character description and analysis. The following list includes 52 characters (see matrix, Table 1), selected out of 90 screened traits mostly because they were amenable to reasonably objective coding. Some of them have been used before, but all relevant anatomical material was reevaluated; I compare my interpretations mainly against those of Valdez-Moreno (1997, 2005) and Mirande (2010). Many characters (22) are binary, but most are multistate, non-additive, unordered. I did not exclude autapomorphies, because they provide special support for species diagnoses (Schmitter-Soto, unpubl. data); to avoid bias, I did not leave out polymorphic and other highly homoplastic traits either. Gill arches, characters 1–6 1. Upper pharyngeal tooth plates, contour [0] oval, fusiform (Fig. 1a); [1] crescent-shaped (Fig. 1b); [2] S-shaped (Fig. 1c) Fifteen steps, ci=0.20, ri=0.14. State 1, homoplastically synapomorphic for A. cf. fasciatus “Ceará” + A. panamensis; state 2, homoplastically synapomorphic for the northern Mexican-Texan clade. Several polymorphisms and homoplastic autapomorphies. This is Valdez-Moreno’s (1997) character 20, where she distinguished two states, similar to the ones established here: 0, oval; 1, S-shaped; apparently she conflated my states 0 and 1 into her state 0.

FIGURE 1. Upper pharyngeal tooth plates: (a) oval, fusiform (Astyanax aeneus, UMMZ 191719); (b) crescent-shaped (A. panamensis, GCRL 13409); (c) S-shaped (A. “Quiché”, UMMZ 193886). Bars are 0.2 mm long.

2. Lower pharyngeal tooth plates [0] single (Fig. 2a); [1] double (Fig. 2b) State 1 occurs only in A. cocibolca and A. “Costa Rica”, convergent autapomorphies; two steps, ci=0.50, ri=0.00.

FIGURE 2. Lower pharyngeal tooth plates: (a) single (Astyanax aeneus, UMMZ 178568), illustrating also caudal side concave; (b) double (A. “Costa Rica”, UMMZ 243884), illustrating also caudal side straight.

PHYLOGENY OF ASTYANAX

Zootaxa 4109 (2) © 2016 Magnolia Press ·

103

3. Lower pharyngeal tooth plates, caudal side [0] concave (Fig. 2a); [1] straight (Fig. 2b) Synapomorphic homoplastically for A. cf. fasciatus “das Velhas” + A. cocibolca and for B. bransfordii + A. nasutus; also in A. “Costa Rica”. Three steps, ci=0.33, ri=0.50. 4. Epibranchial III, insertion of uncinate process [0] widely open, “hyperbolic” (Fig. 3a); [1] rather closed, semicircular (Fig. 3b) State 1 is synapomorphic for “A. fasciatus s. lat.” (i.e. all Central American and Mexican Astyanax species, plus A. fasciatus s. str. and other Brazilian material close to A. fasciatus). Nine steps; rather homoplastic (ci=0.22), but providing some structure (ri=0.50). A synapomorphic reversion to state 0 for the clade A. nicaraguensis + (A. cf. fasciatus “das Velhas” + A. cocibolca); also autapomorphically in A. “Petén”, A. aeneus, A. “Tehuacán”, and A. mexicanus. Some species polymorphic.

FIGURE 3. Epibranchial III, insertion of uncinate process: (a) widely open; distal segment straight (Astyanax “Texas”, UMMZ 170107); (b) rather closed; distal segment curved (A. “Acatlán”, UMMZ 191698). Bars are 0.5 mm long.

5. Epibranchial III, main body, distal segment [0] straight (Fig. 3a); [1] curved (Fig. 3b) Seven steps, ci=0.29, ri=0.17. A synapomorphy for the northern Mexican-Texan clade, autapomorphical in A. “Veracruz”, polymorphic in several species. 6. Gill rakers, first arch, total number [0] 26 or more; [1] 19–26, mean 22–25; [2] 18–23, mean 20–21; [3] 16–20, mean 17–19 Fourteen steps, ci=0.29, ri=0.17. State 1 is synapomorphic for the studied Astyanax; state 2, synapomorphic for the northern Mexican-Texan clade, as convergent autapomorphies in Hyphessobrycon and several Astyanax. State 3 is an autapomorphy for A. cocibolca, occurring also in Roeboides. This was one of the classic diagnostic characters used to key out “A. mexicanus” sensu Miller et al. (2009), i.e. including A. “Quiché”, with state 2, vs. “A. aeneus” s. lat., supposedly with state 1 (actually polymorphic for the trait). Hyoid series, characters 7–10 7. Urohyal, ventrorostral edge [0] convex, uniform (Fig. 4a); [1] angled (Fig. 4b); [2] spiny (Fig. 4c) Three steps, ci=1.00, ri=0.00; states 1 and 2 are strict autapomorphies for A. cf. fasciatus “Ceará” and A. “Tehuacán”, respectively. Astyanax “Quiché” is polymorphic for the trait. 8. Urohyal, ventral apex [0] almost at caudal end (Fig. 4d); [1] about equidistant between rostral and caudal ends (Fig. 4a); [2] somewhat closer to caudal end (Fig. 4b) Seventeen steps, ci=0.18, ri=0.13. In addition to convergent autapomorphies for several Astyanax, state 1 is homoplastically synapomorphic for A. cf. fasciatus “Ceará” + A. panamensis; also in Roeboides. State 2 is a synapomorphy for all the studied Astyanax, with a reversion to state 1 in A. atratoensis. A reversion to state 0 is autapomorphic for B. dorioni and for A. “Tamazulapan”. Astyanax “Costa Rica”, A. “Petén”, and A. nicaraguensis are polymorphic for the trait.


SCHMITTER-SOTO

Valdez-Moreno (1997) found all characteristics of the urohyal to be variable, except the rostral tip, her character 17, which she coded as “round”, state 0, vs. “pointed”, state 1. The bone was more useful at the generic level: Valdez-Moreno (2005) used its relative length and thickness as her characters 69 and 70, respectively.

FIGURE 4. Urohyal: (a) ventrorostral edge convex, uniform; ventral apex about equidistant between rostral and caudal ends (Astyanax mexicanus, UMMZ 169835); (b) ventrorostral edge angled; ventral apex closer to caudal end (A. “Quiché”, UMMZ 161769); (c) ventrorostral edge with a spine (arrow) (A. “Tehuacán”, UMMZ 198853); (d) ventrorostral edge convex; ventral apex almost at caudal end (A. “Tamazulapan”, UMMZ 234194). Bars are 1 mm long.

9. Ceratohyal, foramen [0] oval (Fig. 5a); [1] drop-shaped (Fig. 5b); [2] circular; [3] comet-shaped (Fig. 5c); [4] absent Fifteen steps, ci=0.33, ri=0.09. State 1 is homoplastically autapomorphic for A. atratoensis, A. “Campeche”, and B. dorioni. State 2 is a strict autapomorphy for A. cf. fasciatus “das Velhas”. State 3 occurs convergently in two Brazilian species and in A. nasutus; state 4, in B. bransfordii, A. “Macal”, and A. “Texas”. Three out of seven species in the Atlantic southern Mexican-Guatemalan clade are polymorphic for the trait.

FIGURE 5. Ceratohyal: first three specimens, rostral vertices angled: (a) foramen oval (Astyanax mexicanus, UMMZ 169835); (b) foramen drop-shaped (A. “Campeche”, UMMZ 196571); (c) foramen comet-shaped (A. cf. fasciatus “Alto São Francisco”, UMMZ 216281); (d) foramen oval, rostral vertices round (A. “Bacalar”, UMMZ 196540). Bars are 0.5 mm long.



105

10. Ceratohyal, rostral vertices [0] round (Fig. 5d); [1] angled (Fig. 5a,b,c) Ten steps, ci=0.20, ri=0.33. State 1 is synapomorphic for the subgenus Astyanax; several reversions and polymorphisms lower the consistency for this character. Neurocranium, characters 11–18 11. Anterior fontanel, length [0] longer (Fig. 6a); [1] shorter (Fig. 6b) Nine steps, ci=0.22, ri=0.42. State 1 is homoplastically synapomorphic for Astyanax cf. fasciatus “Ceará” + A. panamensis, for A. “Rioverde” + A. “Texas”, and for the Atlantic southern Mexican-Guatemalan clade, with a reversion to state 0 for A. “Campeche” + A. “Ocotal” and polymorphisms in A. “Petén” and A. “Quiché”.

FIGURE 6. Anterior fontanel: (a) longer, sides convex at mid-length (arrow), tip sharp (Astyanax “Texas”, UMMZ 170107); (b) shorter, sides straight at mid-length (arrow), tip blunt (A. “Veracruz”, UMMZ 97336).

12. Anterior fontanel, sides [0] straight (Fig. 6b); [1] convex (Fig. 6a) Five steps, ci=0.40, ri=0.50. State 1 is homoplastically synapomorphic for Astyanax cf. fasciatus “Alto São Francisco” + A. “Macal” + A. altior, and A. “Rioverde” + A. “Texas”, with two other autapomorphies. Polymorphic for A. “Costa Rica”. 13. Anterior fontanel, rostral tip [0] blunt (Fig. 6b); [1] sharp (Fig. 6a) Fifteen steps, ci=0.20, ri=0.20. State 1 is synapomorphic for the two Nicaraguan clades and also for A. “Rioverde” + A. “Texas”, with the strictly autapomorphic state 2 for A. cf. fasciatus “das Velhas”. Several polymorphisms. 14. Caudal side of supraoccipital, lateral view [0] undulate to straight (Fig. 7a); [1] slightly concave (Fig. 7b); [2] convex (Fig. 7c); [3] angled (Fig. 7d); [4] strongly concave. Nineteen steps, ci=0.26, ri=0.26. State 1 is homoplastically synapomorphic for A. atratoensis + the large clade that includes A. fasciatus s.s. and A. aeneus. State 2 is a strict autapomorphy for A. orthodus; state 3 occurs in A. nasutus, A. nicaraguensis, A. “Veracruz”, and A. “Tehuacán”, with state 4 a convergent autapomorphy for B. bransfordii and for A. “Tamazulapan”. Polymorphisms and reversions to state 0 in the sister group to A. “Veracruz”.


SCHMITTER-SOTO

FIGURE 7. Supraoccipital, caudal side: (a) undulate to straight (Brycon guatemalensis, UMMZ 190656); (b) slightly concave (Astyanax mexicanus, UMMZ 169835); (c) convex (A. orthodus, UMMZ 160225); (d) angled (A. “Veracruz”, UMMZ 191727) . Bars are 1 mm long.

15. Supraoccipital, caudal process, dorsal view [0] longer, narrow-based (Fig. 8a); [1] shorter, wide-based (Fig. 8b) Nine steps, ci=0.11, ri=0.20. State 1 is a synapomorphy for the studied species of Astyanax + Hyphessobrycon, with several reversions, including one for B. bransfordii + A. nasutus. This is Valdez-Moreno’s (1997) character 26, same coding and polarity. We do, however, differ in particular evaluations: e.g., she found A. “Veracruz”, which she considered a series of intergrades between southern and northern forms, to be polymorphic for the trait (nine populations examined), while state 1 is found here to be constant for the species (eight populations examined). Mirande (2010) separated the length of the supraoccipital spine in two binary characters, comparing it to the length of the neural complex of the Weberian apparatus: in state 0 of his character 52, the spine is as long as the complex; state 1 of character 52, to one half the extent of the complex; state 0 of character 53 includes both states of character 52 (“spine extends to at least middle length of complex”); state 1 of character 53, only to anterior limit of complex. Apparently, we coincide in the polarity found, and he faced several polymorphisms as well.

FIGURE 8. Supraoccipital, dorsal view: (a) longer, narrow-based (Astyanax aeneus, UMMZ 178568); (b) shorter, wide-based (A. “Quiché”, UMMZ 173731) . Bars are 0.5 mm long.

16. Interorbital width [0] mean 8% SL or less; [1] mean 9% SL or more. Eleven steps, ci=0.18, ri=0.47. State 1, synapomorphic for Astyanax; reversions to state 0 for Panamanian and Nicaraguan clades. Several polymorphisms. The character was considered suitable for cladistic analysis because, unlike an osteologically composite measurement (like head length), interorbital width involves only the frontal bones. For coding, see Methods (ANOVA results available from the author on request). PHYLOGENY OF ASTYANAX


107

17. Supracephalic profile [0] convex (Fig. 9a); [1] concave (Fig. 9b) Seventeen steps, ci=0.12, ri=0.21. State 1, synapomorphic for the studied Astyanax (parallel in Roeboides); a reversion to state 0 is synapomorphic for the clade A. mexicanus + (A. “Rioverde” + A. “Texas”). The clade B. bransfordii + A. nasutus is polymorphic, as are 50% of the species in the Atlantic southern Mexican-Guatemalan the clade and elsewhere. As in character 16, this externally observable trait involves only the frontal bones.

FIGURE 9. Supracephalic profile: (a) convex (Astyanax mexicanus, UMMZ 169835); (b) concave (Astyanax aeneus, UMMZ 178568).

Infraorbitals, characters 18–21 18. Infraorbital II [0] rectangular; [1] triangular, base short, angled (Fig. 10a); [2] triangular, base short, convex (Fig. 10b); [3] an elongated triangle, base angled (Fig. 10c); [4] triangular, base with two angles (Fig. 10d); [5] triangular, base long, convex (Fig. 10e) Thirteen steps, ci=0.46, ri=0.13. State 1, synapomorphic for the studied species of Astyanax. State 2 appears in parallel in Hyphessobrycon, A. orthodus, and others. State 3 is a strict autapomorphy for A. cf. fasciatus “das Velhas”; state 4, for B. bransfordii. State 5 evolved frequently in the A. mexicanus clade, or else may be interpreted as synapomorphic, with a reversion to state 1 in A. “Rioverde”; parallel in A. “Tamazulapan”. Trait polymorphic in A. “Belize”. This is Valdez-Moreno’s (1997) character 1. State 0 is the same, but she discerns just two more states: 1, inferoposterior edge (“base”) short, and 2, long; I concur with her in finding a longer base in the northern form (A. “Texas”). Valdez-Moreno (2005) distinguished two characters for the bone: anterior shape (square vs. triangular) and posterior shape (square, semicircular, globose, or triangular). 19. Infraorbital III, infraposterior side [0] angled, hyperbolic (Fig. 11a); [1] semicircular (Fig. 11b) Eleven steps, ci=0.18, ri=0.10. State 1, synapomorphic for Astyanax + Hyphessobrycon; several reversions and polymorphisms. Valdez-Moreno (1997) coded this bone as her character 2, with three states: 0, squarish, equivalent to what I call “angled” or hyperbolic; 1, semicircular with dorsoposterior projection, and 2, semicircular without such projection. I find the alleged projection to be very variable, even within populations; her states 1 and 2 appear in populations of A. “Veracruz”, a species which I also find polymorphic, but for my states 0 and 1. On the other hand, the polarity was found to be the same.


SCHMITTER-SOTO

FIGURE 10. Infraorbital II: (a) triangular, base short, angled (Astyanax “Rioverde”, UMMZ 192510); (b) triangular, base shorter, convex (A. aeneus, UMMZ 178568); (c) an elongated triangle, base angled (A. cf. fasciatus “das Velhas”, UMMZ 216372); (d) triangular, base with two angles (B. bransfordii, FMNH 5919); (e) triangular, base longer, convex (A. mexicanus, UMMZ 169835). Bars are 0.5 mm long.

FIGURE 11. Infraorbital III, infraposterior side: (a) angled, hyperbolic (Astyanax aeneus, UMMZ 144617); (b) semicircular (A. mexicanus, UMMZ 169835).

20. Infraorbital IV [0] square, no projections (Fig. 12a); [1] square, with a rostroventral projection (Fig. 12b); [2] pentagonal (Fig. 12c); [3] rectangular, no projections (Fig. 12d); [4] rectangular, with projections (Fig. 12e) Fourteen steps, ci=0.36, ri=0.36. State 1, synapomorphic for the studied species of Astyanax. State 2, a strict autapomorphy for A. bimaculatus; state 3, for A. cf. fasciatus “das Velhas”. State 4 is homoplastically synapomorphic for the Atlantic southern Mexican-Guatemalan clade and for A. “Rioverde” + A. “Texas”. This bone is triangular in Roeboides (Valdez-Moreno 2005). This is Valdez-Moreno’s (1997) character 3, same polarity found, although she splits my state 1 in two: 1, projection smaller; 2, projection larger, and she omits my states 3 and 4. Her states 1 and 2 occur polymorphically



109

in A. “Veracruz”, A. “Tamiahua”, and A. “Texas”, which reinforces my view that they should be considered only one state (with projection). This is also Mirande’s (2010) character 67, but he conflates all of my states into his state 0, square or longer longitudinally, and recognizes only one other state, longer dorsoventrally than longitudinally, which does not occur in any of the species I studied. His character 68 deals with a posterior dorsoventral expansion which does not correspond to any of my states, although it is reminiscent of what I describe as pentagonal, my state 2, a form that he found in Oligosarcus.

FIGURE 12. Infraorbital IV: (a) square, no projections (Astyanax “Tamiahua”, UMMZ 167489); (b) square, with a rostroventral projection (A. mexicanus, UMMZ 169835); (c) pentagonal (A. bimaculatus, UMMZ 206863); (d) rectangular, no projections (A. cf. fasciatus “das Velhas”, UMMZ 216372); (e) rectangular, with a projection (A. “Texas”, UMMZ 170107). Bars are 0.5 mm long, except in (a), which is 0.2 mm long.

21. Contact between infraorbital II and III [0] wider; [1] narrower Eight steps, ci=0.25, ri=0.00. State 1 is homoplastically autapomorphic for A. aeneus, A. nicaraguensis, and A. “Tamazulapan”; several instances of polymorphism. Mouth and jaws, characters 22–28 22. Mouth [0] upper lip protruding; [1] not upturned, even; [2] upturned; [3] lower lip protruding; [4] elongated Ten steps, ci=0.40, ri=0.14. State 1, synapomorphic for the studied species of Astyanax + Hyphessobrycon. State 2, convergently autapomorphic for A. “Macal” and for A. cocibolca; same situation for state 3, for A. nicaraguensis and for A. nasutus. State 4 arose independently in all species of Bramocharax, including A. “Ocotal”, considered a Bramocharax by Valdez-Moreno (2005).


SCHMITTER-SOTO

23. Metapterygoid, dorsorostral projections [0] none (Fig. 13a); [1] one (Fig. 13b); [2] two (Fig. 13c) Thirteen steps, ci=0.23, ri=0.23. State 2 is synapomorphic for the studied species of Astyanax + Hyphessobrycon; state 1, homoplastically synapomorphic for A. cf. fasciatus “Ceará” + A. panamensis and for the Nicaraguan clade that includes A. cf. fasciatus “das Velhas”; also in Roeboides and other Astyanax. Several polymorphisms. This is Valdez-Moreno’s (1997) character 15, with three states, although she includes not only the number of dorsorostral projections, but also the absence of a foramen in state 0; however, the foramen can also be absent in state 2 (see Fig. 12c). I agree with her that A. aeneus, A. “Veracruz”, and A. “Texas” are polymorphic for the trait. Valdez-Moreno (2005) used five characters from this bone. Her character 54, state 0, dorsoposterior margin with two processes, was a synapomorphy uniting Bramocharax, Astyanax, Deuterodon, and Knodus.

FIGURE 13. Metapterygoid: (a) no dorsorostral projections, rostral arm somewhat longer than ventral (Brycon guatemalensis, UMMZ 190656); (b) one dorsorostral projection, rostral arm much longer (Astyanax fasciatus, UMMZ 216281); (c) two such projections, arms subequal (B. dorioni, UMMZ 193918). Bars are 1 mm long.

24. Arms of metapterygoid [0] rostral arm somewhat longer than ventral (Fig. 13a); [1] rostral much longer than ventral (Fig. 13b); [2] arms subequal (Fig. 13c) Five steps, ci=0.50, ri=0.75. State 1, a strict synapomorphy for the subgenus Astyanax; state 2, strictly autapomorphic for A dorioni. A reversion to state 0, synapomorphic for B. bransfordii + A. nasutus. Polymorphism in A. “Costa Rica”. 25. Quadrate dorsal process [0] distally expanded (Fig. 14a); [1] not expanded (Fig. 14b) Thirteen steps, ci=0.15, ri=0.27. State 1, synapomorphic for the studied species of Astyanax + Hyphessobrycon. A reversion to state 0, synapomorphic for the clade including A. mexicanus and for the Atlantic southern Mexican-Guatemalan clade; convergently autapomorphic in other species, including some Bramocharax. Polymorphisms. Valdez-Moreno (2005) coded this same character (her character 49) differently, with state 0 as “semicircular” vs. state 1 as “straight”, the latter a synapomorphy for all characid genera studied by her.

FIGURE 14. Dorsal process of quadrate: (a) distally expanded, process narrower (Astyanax mexicanus, UMMZ 169835); (b) not expanded, process wider (A. aeneus, UMMZ 178568). Bars are 0.5 mm long.



111

26. Arms of premaxilla [0] dentigerous longer (Fig. 15a); [1] subequal (Fig. 15b) Fifteen steps, ci=0.13, ri=0.00. State 1 could be interpreted as a synapomorphy for the Atlantic southern Mexican-Guatemalan clade followed by a reversion to state 0 in most of its species, parallel in A. aeneus and others.

FIGURE 15. Premaxilla: (a) dentigerous arm longer (Astyanax “Tamazulapan”, UMMZ 234194); (b) arms subequal (A. aeneus, UMMZ 178568). Bars are 1 mm long.

27. First row of premaxillary teeth [0] with nine teeth or more; [1] with three to five teeth (Fig. 15); [2] with two teeth Four steps, ci=0.50, ri=0.33. State 1 is a synapomorphy for the studied Astyanax + Hyphessobrycon, some species having 3–4, others 4–5, but most of them constantly with four teeth. State 2 is an homoplastic synapomorphy for A. cf. fasciatus “das Velhas” + A. cocibolca, the latter being the sole Central American species with this trait, convergent in A. orthodus, in A. cf. fasciatus “Ceará”, and in Roeboides. Mirande (2010) coded this trait differently, as two binary characters: 129, with states 0, four or fewer teeth, and 1, five or more; and character 130, states 0, seven or fewer teeth, and 1, eight or more. He coincides with the classic distinction by Eigenmann (1921) of genera with four teeth, such as Bryconamericus, and genera “with five teeth”, such as Astyanax. I do not find such constancy in the latter genus. 28. Premaxillary teeth rows [0] three; [1] two (Fig. 15) One step, ci=1.0, ri=0.0. State 1 is a strict synapomorphy for the studied species of Astyanax + Hyphessobrycon (also in Roeboides). The character was used also by Valdez-Moreno (1997), same polarity found; nevertheless, in a subsequent multigeneric cladogram (Valdez-Moreno 2005), having three rows of teeth on the premaxilla turned out to be a synapomorphy for genus Brycon, the condition of having only two rows being plesiomorphic, which is also the view of Zanata & Vari (2005) for the Characiformes. This corresponds to Mirande’s (2010) binary character 123, with one or two rows as state 0, typical of most of the Characidae, and three rows as state 1, a homoplastic synapomorphy for various clades, including the one containing Brycon. He discusses potential problems in recognizing homology in this character. Opercular series, characters 29–35 29. Dorsal half of opercle [0] sides about parallel at mid-length (Fig. 16a); [1] sides divergent (Fig. 16b) One step, ci=1.00, ri=0.00. State 1 is a strict autapomorphy for A. “Tehuacán”.


SCHMITTER-SOTO

FIGURE 16. Sides of upper half of opercle: (a) about parallel at mid-length (Astyanax “Macal”, UMMZ 178599); (b) divergent at mid-length (A. “Tehuacán”, UMMZ 198853). Bars are 1 mm long.

30. Interopercle [0] longer; [1] shorter One step, ci=1.00, ri=0.00. State 1 is a strict synapomorphy for the studied species of Astyanax + Hyphessobrycon, also in Roeboides. Valdez-Moreno (1997) first proposed this character, with the same interpretation. 31. Posterior edge of interopercle [0] with an angle (Fig. 17a); [1] convex, without any angle (Fig. 17b)

FIGURE 17. Interopercle, caudal edge: (a) with an angle (arrow) (Astyanax mexicanus, UMMZ 169835); (b) no such angle (A. “Texas”, UMMZ 170107). Bars are 1 mm long.



113

Fifteen steps, ci=0.13, ri=0.24. State 1, homoplastically synapomorphic for A. bimaculatus + A. orthodus, for the clade including A. nicaraguensis, and for A. “Texas” + A. “Rioverde”; also in Hyphessobrycon and others. Several polymorphisms. 32. Subopercular dorsorostral projection [0] absent; [1] present One step, ci=1.00, ri=0.00. State 1 is a strict synapomorphy for the studied species of Astyanax. This is Valdez-Moreno’s (1997) character 14, same interpretation. 33. Preopercular ventral rim [0] straight, at least anteriorly (Fig. 18a); [1] convex (Fig. 18b) Five steps, ci=0.40, ri=0.00. State 1 appears autapomorphically in parallel in A. “Acatlán”, A. “Tamazulapan”, and A. “Rioverde”; polymorphisms in A. “Costa Rica” and A. “Veracruz”. Valdez-Moreno (1997) combined this trait and the following one into her character 12, with three states: 0, ventral rim straight and anterodorsal edge concave; 1, ventral rim curved and anterodorsal edge convex; 2, ventral rim curved and anterodorsal edge concave. Her state 1 apparently occurred only in one population of A. “Texas”.

FIGURE 18. Preopercle: (a) ventral rim nearly straight, anterodorsal edge straight-concave (Astyanax cf. fasciatus “Alto São Francisco”, UMMZ 216281); (b) ventral rim convex (A. “Rioverde”, UMMZ 192510); (c) anterodorsal edge with a median convexity, arrow (A. “Campeche”, UMMZ 143428). Bars are 1 mm long.

34. Preopercular anterodorsal edge [0] straight-concave (Fig. 18a); [1] with a median convexity (Fig. 18c) Thirteen steps, ci=0.15, ri=0.39. State 1, synapomorphic for the studied Astyanax; synapomorphic reversions to state 0 at the larger clades for Atlantic southern Mexico-Guatemala and central-northern Mexico, with several polymorphisms. 35. Preopercular canals [0] two (Fig. 18); [1] one One step, ci=1.0, ri=0.0. State 1 is a strict autapomorphy for A. cocibolca. Axial skeleton, characters 36–37 36. Edge of epuric plate on last neural spine [0] concave; [1] straight, not indented (Fig. 19a); [2] convex, not indented (Fig. 19b); [3] straight, indented (Fig. 19c); [4] roundish, indented (Fig. 19d) Eighteen steps, ci=0.28, ri=0.13. State 1, synapomorphic for the studied Astyanax. State 2, synapomorphic for A. nasutus + B. bransfordii and for the northern Mexican-Texan clade. State 3, convergently autapomorphic for A. nicaraguensis, A. “Cubilhuitz”, and B. caballeroi. State 4, a strict autapomorphy for B. dorioni. Polymorphisms in the Atlantic southern Mexican-Guatemalan clade.


SCHMITTER-SOTO

FIGURE 19. Edge of epuric plate on last neural spine (arrows): (a) straight, no indentation (Astyanax orthodus, UMMZ 160225); (b) convex, no indentation (A. “Texas”, UMMZ 170107); (c) straight, indented (A. “Rioverde”, UMMZ 192510); (d) roundish, indented (A. “Quiché”, UMMZ 186378)

37. Total vertebrae [0] 42; [1] 34; [2] 32 or 33; [3] 31 Eleven steps, ci=0.36, ri=0.13. State 1 is strictly autapomorphic for A. atratoensis; state 2, a synapomorphy for genus Astyanax; state 3, a synapomorphy for subgenus Astyanax. Autapomorphic reversions to state 2 in A. cf. fasciatus “Ceará”, A. “Quiché”, B. caballeroi, and A. nasutus. Astyanax “Costa Rica and A. nicaraguensis are polymorphic for this trait. Mirande (2010) coded the character with just two states: 0, 40 vertebrae or fewer, which includes my states 13; and state 1, 41 vertebrae or more. He acknowledged that this coding is “rather subjective”; most of the characids that he examined had 35-38 vertebrae. Squamation, characters 38–42 38. Scales on lateral line [0] 48 or more; [1] 43 or fewer One step, ci=1.00, ri=1.00. State 1 is a strict synapomorphy for the studied species of Astyanax. 39. Scale rows between lateral line and pelvic fin origin [0] mean 5 or 6; [1] mean 7 or 8; [2] mean 4 Six steps, ci=0.50, ri=0.00. State 1, homoplastically autapomorphic for A. atratoensis, A. “Macal”, and A. “Costa Rica”; state 2, for A. cf. fasciatus “das Velhas” and A. orthodus. Astyanax panamensis is polymorphic for the trait. 40. Predorsal scales [0] mean 16; [1] mean 11–13; [2] mean 10 Six steps, ci=0.50, ri=0.40. State 1 is synapomorphic for the studied species of Astyanax. State 2 is a strict autapomorphy for A. “Tamiahua”. Polymorphism in several South American species and also in A. “Macal”.



115

41. Predorsal scale series [0] incomplete, an unscaled space behind tip of supraoccipital process (Fig. 20a); [1] complete to caudal tip of supraoccipital process (Fig. 20b) The character was originally proposed by Eigenmann (1921) to separate his subgenera Poecilurichthys and Astyanax. Two steps, ci=0.50, ri=0.67; state 1 is a synapomorphy for the subgenus Astyanax (parallel in Hyphessobrycon), to the exclusion of species in Poecilurichthys (A. atratoensis, A. bimaculatus, A. orthodus); the latter subgenus is not recovered as monophyletic. Mirande (2010) found the opposite polarity for this character.

FIGURE 20. Predorsal scale series: (a) incomplete at nape, arrow (Astyanax bimaculatus, UMMZ 206863); (b) complete to supraoccipital (A. aeneus, UMMZ 178568).

42. Scaly sheath at anal fin base [0] with imbricated scales, long; [1] simple, long; [2] simple, short; [3] with imbricated scales, short Eight steps, ci=0.50, ri=0.50. State 1, synapomorphic for genus Astyanax. State 2, synapomorphic for subgenus Astyanax sensu Eigenmann (1921). State 3, a strict autapomorphy for B. dorioni. Autapomorphic reversions to state 0 in A. panamensis, A. cocibolca, B. bransfordii, and A. altior. Astyanax “Costa Rica” is polymorphic for the trait. Fins, pectoral and pelvic girdles, characters 43–51 43. Anal-fin rays [0] mean 33–36; [1] mean 28–30; [2] mean 25–27; [3] mean 21–24; [4] mean 19 Eighteen steps, ci=0.28, ri=0.24. State 1 is a strict synapomorphy for A. orthodus + A. bimaculatus. State 2 is homoplastically synapomorphic for A. nasutus + B. bransfordii, autapomorphic for several species formerly in Bramocharax and for A. aeneus, A. fasciatus “Alto São Francisco”, A. “Belize”, and Hyphessobrycon. State 3 is synapomorphic for the subgenus Astyanax sensu Eigenmann (1921); state 4, a strict autapomorphy for A. “Rioverde”. Several polymorphisms. Mirande (2010) split this multistate character into four binary characters. He observes that “its phylogenetic utility may be mostly restricted to the resolution of rather small clades.” In his view, a low rather than a high number of rays is the plesiomorphic state, because most non-characid Characiformes have few anal-fin rays; his character 286, state 1, 11 rays or more, is typical of most Characidae. 44. First branched anal-fin ray [0] width about normal (Fig. 21a); [1] noticeably wider than the rest (Fig. 21b) Eight steps, ci=0.25, ri=0.40. State 1 is homoplastically synapomorphic for A. bimaculatus + A. orthodus and the two Nicaraguan clades; autapomorphic in most former Bramocharax species and A. “Tamazulapan”. Polymorphism in A. “Costa Rica” and A. panamensis.


SCHMITTER-SOTO

FIGURE 21. First unbranched anal-fin ray: (a) about same width as the rest, arrow (Astyanax “Texas”, UMMZ 170107); (b) noticeably wider than the rest (B. dorioni, UMMZ 193918).

45. Post-anal element [0] shorter (Fig. 22a); [1] longer (Fig. 22b) Four steps, ci=0.50, ri=0.00. State 1 is parallel for A. “Petén” and B. bransfordii. Polymorphic in A. “Belize” and A. “Quiché”.

FIGURE 22. Post-anal element (arrow): (a) shorter (Astyanax “Texas”, UMMZ 170107); (b) longer (B. bransfordii, FMNH 5919).

46. Predorsal elements [0] 11; [1] 4–6 One step, ci=1.00, ri=1.00. State 1 is a strict synapomorphy for the studied Astyanax. This is Mirande’s (2010) character 281 (as “number of supraneurals”), opposite polarity found, with states 0 and 1 defined respectively by him as seven or fewer vs. eight or more. 47. First dorsal pterygiophore, rostral edge [0] curved (Fig. 23a); [1] with a spine (Fig. 23b) Nine steps, ci=0.22, ri=0.30. State 1, synapomorphic for subgenus Astyanax sensu Eigenmann (1921), parallel in A. bimaculatus. Synapomorphic reversal to state 0 for A. nicaraguensis + (A. cocibolca + A. cf. fasciatus “das Velhas”). Polymorphism in A. mexicanus, A. “Campeche”, and A. “Bacalar”. PHYLOGENY OF ASTYANAX


117

FIGURE 23. First dorsal pterygiophore, rostral edge: (a) curved (Astyanax “Costa Rica”, UMMZ 159153); (b) angled (A. “Rioverde”, UMMZ 192510).

48. Cleithrum, suture to coracoid [0] single, deep, with two convexities (Fig. 24a); [1] 2–3 interdigitations (Fig. 24b); [2] 4–5 interdigitations (Fig. 24c); [3] single, triangular, broad (Fig. 24d); [4] 6 interdigitations (Fig. 24e) Eleven steps, ci=0.46, ri=0.14. State 1, synapomorphic for Astyanax. State 2, homoplastically autapomorphic for A. “Ocotal” and A. altior. State 3, strict autapomorphy for B. caballeroi; state 4, for A. “Rioverde”. A reversion to state 0 is synapomorphic for A. cocibolca + A. cf. fasciatus “das Velhas”, autapomorphic for A. “Cubilhuitz”. Polymorphisms in A. aeneus and other species.

FIGURE 24. Suture cleithrum-coracoid: (a) single, deep, with two convexities or angles (Astyanax “Quiché”, UMMZ 173731); (b) with 2–3 interdigitations (A. “Texas”, UMMZ 186469); (c) with 4–5 interdigitations (Oaxacan A. aeneus, UMMZ 184801); (d) single, triangular, broal (Honduran A. aeneus, UMMZ 144617); (e) six interdigitations (A. “Rioverde”, UMMZ 192510). Bars are 0.5 mm long, except in (c) and (e), 1 mm.


SCHMITTER-SOTO

49. Postcleithrum, caudal process [0] concave-sided dorsally and ventrally (Fig. 25a); [1] concave-sided dorsally, almost straight ventrally (Fig. 25b); [2] squarish (Fig. 25c); [3] concave-sided, with a dorsal angle (Fig. 25d); [4] straight-sided, with a ventral proximal indentation (Fig. 25e) Nineteen steps, ci=0.26, ri=0.18. State 1 is homoplastically synapomorphic for A. nicaraguensis + (A. cf. fasciatus “das Velhas” + A. cocibolca); state 2, autapomorphic for A. cf. fasciatus “Ceará”, A. aeneus, A. “Tamiahua”, B. dorioni, and B. bransfordii; state 3, synapomorphic for the Atlantic southern Mexican-Guatemalan clade, with several polymorphisms. State 4 is a strict autapomorphy for A. mexicanus.

FIGURE 25. Postcleithrum, caudal process: (a) concave-sided (Brycon guatemalensis, UMMZ 190656); (b) concave-sided dorsally, almost straight ventrally (Astyanax “Veracruz”, UMMZ 184761); (c) squarish (A. aeneus, UMMZ 178490); (d) concave-sided, with a dorsal angle (A. “Quiché”, UMMZ 161739); (e) straight-sided, with a ventral proximal indentation (A. mexicanus, UMMZ 169835).

50. Pelvic bone, proximal edge [0] curved to irregular (Fig. 26a); [1] straight (Fig. 26b) Three steps, ci=0.33, ri=0.33. State 1, synapomorphic for the A. nicaraguensis clade, autapomorphic for A. “Quiché” and B. dorioni.

FIGURE 26. Pelvic bone, proximal edge: (a) curved (Astyanax aeneus, UMMZ 178568); (b) straight (A. “Quiché”, UMMZ 193886).

51. Caudal fin lobes [0] subequal; [1] inferior longer Three steps, ci=0.33, ri=0.0. State 1, parallel in A. “Macal”, A. panamensis, and A. cocibolca.



119

Coloration, character 52 52. Caudal spot [0] on peduncle and on rays; [1] not on rays, only on peduncle Two steps, ci=0.50, ri=0.00. State 1 is a convergent autapomorphy for A. atratoensis and A. panamensis.

Phylogeny Forty-three equally most parsimonious trees were recovered. The strict consensus tree is 454 steps long (CI=0.289, RI=0.264, Fig. 27; matrix shown in Table 1). Synapomorphies are mentioned above for every character concerned. The genus Astyanax is recovered as monophyletic, but, to test this further, many more genera need to be included. Astyanax atratoensis is the sister group to the larger clade of Central American and Mexican Astyanax, i.e., the subgenus Astyanax, monophyletic, including four South American species. On the contrary, the subgenus Poecilurichthys is not recovered as monophyletic. Five clades stand resolved out of a large polytomy, three of them including one Brazilian species. A purely Nicaraguan (Great Lakes) clade is A. nasutus + B. bransfordii. A second, partly Nicaraguan, clade features the widespread A. nicaraguensis sister to A. cocibolca plus the Brazilian form A. cf. fasciatus “das Velhas”. The northern Brazilian form A. cf. fasciatus “Ceará” is in a same clade with A. panamensis. The largest resolved clade, with nine species, summarized as “Atlantic southern Mexican-Guatemalan” (but again including a South American species, in a derived position), shows the widespread Gulf of Mexico form A. “Veracruz” sister to the rest, which includes an inland central Mexican microendemic, A. “ Acatlán”, in turn sister to a clade with species from northeastern Guatemala, Belize, and southeastern Mexico. Finally, a central-northern Mexican-Texan clade shows the northernmost species in the genus, A. “Texas”, in a derived position. Bramocharax species were not recovered together. Two of them occur in separate resolved clades; the other three Bramocharax occur in the large polytomy corresponding to subgenus Astyanax, same as A. aeneus s. str. (restricted to Pacific southern Mexico and northern Central America) and A. fasciatus s. str. (lower Rio São Francisco, Brazil).

Discussion Eleven out of the 30 cranial characters used by Valdez-Moreno (1997) were also included in the present study, albeit many of them with different decisions on character states. Since hers was a population tree, the comparison to the present hypothesis is not clear, except that northern forms (what I call Astyanax “Texas”) occur in a derived position. Twelve out of the 360 morphological characters used by Mirande (2010) were also used in this analysis; he coded all additive characters as binary, which means that often one of my multistate character corresponds to two or more of his characters. He found B. bransfordii to lie in its own clade (with species of Oligosarcus, one undescribed), outside the Tetragonopterinae. No other authors have found Bramocharax so far away phylogenetically from Astyanax, hypotheses ranging from finding the former genus polyphyletic, every one of its component species being sister to a sympatric species of Astyanax (Ornelas-García et al. 2008), to recovering it as monophyletic if some species are excluded, but making Astyanax paraphyletic if recognized (Valdez-Moreno 1997). Mirande (2010) found his “A. mexicanus” (which corresponds to the form here called A. “Texas”) to be the sister taxon to a clade including many South American Astyanax. The “back to South America” pattern, a recurrent presence of South American species within primarily Middle American clades, has been observed in several groups. For example, Schmitter-Soto (2007) found the South American Caquetaia nested within Middle American cichlids, and Bermingham and Martin (1998) found Roeboides meeki from Colombia within Lower Central American species of the genus. Chakrabarty and Albert (2011) reviewed several Neotropical fish phylogenies suggesting that much of the Central American species diversity can be explained by older biogeographic events


SCHMITTER-SOTO

FIGURE 27. Strict-consensus species cladogram for Middle American Astyanax and comparative material (361 steps, CI 0.363, RI 0.431). Undescribed species of Astyanax are designated by their region or locality. Numbers above lines are apomorphies, with the superindex indicating the character state; for character numbering, see Character description and analysis.



121

TABLE 1. Matrix of characters and species used for parsimony analysis of character distribution in Central American and Mexican Astyanax and Bramocharax. Question marks designate not only unknown states, but also polymorphisms and inapplicable characters. See cladogram in Figure 27. 1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

Brycon

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Hyphessobrycon

0

0

?

0

0

2

0

0

0

0

0

0

?

0

1

0

0

2

Roeboides

0

0

?

0

0

3

0

1

0

?

0

0

?

0

0

?

1

0

“Acatlán”

0

0

0

1

0

2

0

2

?

1

1

0

0

?

1

1

1

2

aeneus

?

0

0

0

?

?

0

?

?

?

0

0

0

?

0

?

1

2

altior

0

0

0

1

?

1

0

2

?

1

1

1

0

?

0

1

1

1

“Campeche”

0

0

0

1

0

1

0

2

1

1

0

0

0

?

1

1

1

1

“Texas”

?

0

?

?

?

2

0

2

4

?

1

1

1

1

1

1

0

5

atratoensis

0

0

0

0

0

1

0

1

1

0

0

0

0

1

1

1

1

1

“Bacalar”

?

0

0

1

0

1

0

2

0

0

1

0

0

?

1

1

?

1

baileyi

?

?

?

?

?

1

?

?

?

?

0

0

0

?

0

0

1

1

“Belize”

1

0

0

1

0

1

0

2

0

0

0

0

?

?

1

0

?

?

bimaculatus

0

0

0

0

0

1

0

2

0

0

?

?

?

0

0

1

1

1

bransfordii

1

0

1

?

?

0

0

2

4

1

0

0

1

4

0

0

?

4

“Quiché”

?

0

0

1

?

2

?

2

?

1

?

0

?

?

1

?

?

1

caballeroi

0

0

0

1

0

1

0

2

0

1

0

0

1

1

0

0

0

1

cf. fasciatus “Alto São Francisco”

0

0

0

?

?

1

0

2

0

1

0

1

1

1

1

1

?

1

cf. fasciatus “Ceará”

1

0

0

1

0

1

0

1

0

0

0

0

0

1

1

0

1

1

cocibolca

2

1

1

0

0

3

0

1

2

1

0

0

2

1

1

0

?

1

“Cubilhuitz”

0

?

?

1

0

1

0

0

1

0

0

0

1

1

1

0

?

1

cf. fasciatus “das Velhas”

0

0

1

0

0

1

0

1

3

1

1

1

1

0

1

0

0

3

dorioni

2

0

0

1

0

1

1

1

3

0

1

0

0

1

1

0

1

1

fasciatus

?

?

?

?

?

1

?

?

?

?

0

0

0

1

1

0

1

?

“Veracruz”

?

0

0

?

1

1

0

1

0

1

1

0

0

3

1

?

1

1

“Macal”

0

?

?

1

0

2

0

2

4

1

1

1

0

0

1

1

?

1

mexicanus

2

0

0

0

1

2

0

1

0

1

0

0

0

1

1

1

0

5

nasutus

2

0

1

?

?

2

0

1

3

1

0

0

1

3

0

?

?

?

nicaraguensis

1

0

0

0

0

1

0

?

0

1

0

0

1

3

1

0

1

2

“Ocotal”

0

0

0

1

0

1

0

?

?

1

0

0

0

0

1

1

1

1

“Costa Rica”

0

1

1

1

?

1

0

?

0

?

?

?

?

?

1

1

?

1

orthodus

?

0

0

0

0

1

0

2

0

0

?

?

?

2

1

1

1

2

panamensis

1

0

0

?

?

1

0

1

?

?

1

0

1

?

1

?

1

2

“Petén”

1

0

0

0

0

1

0

?

0

1

?

0

?

1

1

1

?

1

“Rioverde”

2

0

0

1

1

2

0

2

0

1

1

1

1

?

1

1

0

1

“Tamazulapan”

0

0

0

1

0

2

0

0

0

1

0

0

1

4

1

0

0

5

“Tamiahua”

?

0

0

?

0

2

0

1

?

0

1

1

?

1

0

1

?

1

“Tehuacán”

2

?

?

0

0

2

2

2

0

1

0

0

1

3

0

0

0

1

......continued on the next page


SCHMITTER-SOTO

TABLE 1. (cont.) 19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

Brycon

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Hyphessobrycon

1

0

0

1

2

0

1

0

1

1

0

1

1

?

0

0

0

Roeboides

0

?

0

0

1

0

0

0

2

1

0

1

?

0

0

0

?

“Acatlán”

?

1

?

1

2

1

0

1

1

1

0

1

?

1

1

0

0

aeneus

?

?

1

1

?

1

1

1

1

1

0

1

?

1

0

?

0

altior

1

4

0

1

2

1

1

?

1

1

0

1

1

1

0

0

0

“Campeche”

1

?

0

1

2

1

?

?

1

1

0

1

?

1

0

?

0

“Texas”

1

4

0

1

?

1

0

?

1

1

0

1

1

1

0

0

0

atratoensis

0

1

0

1

2

0

1

0

1

1

0

1

0

?

0

1

0

“Bacalar”

1

?

?

1

2

1

?

?

1

1

0

1

1

1

0

1

0

baileyi

1

1

0

4

?

?

?

0

1

1

0

1

0

?

0

?

0

“Belize”

1

1

0

1

?

1

?

?

1

1

0

1

?

1

0

1

0

bimaculatus

1

2

0

1

2

0

1

0

1

1

0

1

1

1

0

1

0

bransfordii

0

4

0

4

2

0

0

0

1

1

0

1

0

1

0

1

0

“Quiché”

1

4

0

1

2

1

?

?

1

1

0

1

?

1

0

?

0

caballeroi

1

1

0

4

2

1

1

1

1

1

0

1

0

1

0

0

0

cf. fasciatus “Alto São Francisco”

1

1

0

1

1

1

1

0

1

1

0

1

0

1

0

0

0


1

1

0

1

1

1

1

0

2

1

0

1

0

1

0

1

0

cocibolca

1

1

0

2

1

1

1

1

2

1

0

1

1

1

0

1

1

“Cubilhuitz”

1

1

0

1

2

1

0

0

1

1

0

1

0

1

0

1

0


0

3

0

1

1

1

1

0

2

1

0

1

1

1

0

1

0

dorioni

1

4

0

4

2

2

0

0

1

1

0

1

0

1

0

1

0

fasciatus

1

?

0

1

?

?

?

?

?

1

?

?

?

?

0

?

?

“Veracruz”

?

1

0

1

?

1

1

1

1

1

0

1

?

1

?

0

0

“Macal”

1

4

0

2

2

1

1

0

1

1

0

1

0

1

0

1

0

mexicanus

1

1

0

1

2

1

0

?

1

1

0

1

0

1

0

0

0

nasutus

?

?

?

3

2

0

1

?

?

1

0

1

0

?

0

1

0

nicaraguensis

1

?

1

3

1

1

1

0

1

1

0

1

1

1

0

1

0

“Ocotal”

1

4

0

4

2

1

0

0

1

1

0

1

0

?

?

0

0

“Costa Rica”

0

1

?

1

2

?

1

?

1

1

0

1

?

1

?

?

0

orthodus

1

1

0

1

2

0

1

0

2

1

0

1

1

1

0

1

0

panamensis

?

?

?

1

1

0

1

?

1

1

0

1

1

1

0

?

0

“Petén”

1

4

0

1

2

1

0

0

1

1

0

1

0

1

0

?

0

“Rioverde”

0

4

0

1

1

1

0

0

1

1

0

1

1

1

1

0

0

“Tamazulapan”

1

1

1

1

1

1

0

0

1

1

0

1

0

1

1

1

0

“Tamiahua”

1

?

?

1

?

1

1

1

1

1

0

1

?

1

0

?

0

“Tehuacán”

0

1

?

1

1

1

0

0

1

1

1

1

0

1

0

0

0

......continued on the next page



123

TABLE 1 (cont.) 36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

Brycon

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Hyphessobrycon

?

?

0

0

0

1

0

2

0

?

0

?

?

?

?

0

?

Roeboides

?

?

0

0

0

?

0

0

0

?

0

?

?

?

?

0

0

“Acatlán”

?

3

1

0

1

1

2

3

0

0

1

1

1

3

0

0

0

aeneus

?

3

1

0

1

1

2

2

0

0

1

1

?

2

0

0

0

altior

1

3

1

0

1

1

0

3

0

0

1

1

2

?

0

0

0

“Campeche”

?

3

1

0

1

1

2

?

0

0

1

?

1

?

0

0

0

“Texas”

2

3

1

0

1

1

2

3

0

0

1

0

?

?

0

0

0

atratoensis

1

1

1

1

1

0

1

0

0

0

1

0

1

0

0

0

1

“Bacalar”

1

3

1

0

1

1

2

?

0

0

1

?

?

?

0

0

0

baileyi

?

?

1

0

1

1

2

2

1

?

?

?

?

?

?

0

0

“Belize”

?

3

1

0

1

1

2

2

0

?

1

1

1

?

0

0

0

bimaculatus

1

2

1

0

?

0

1

1

1

0

1

1

1

0

?

0

0

bransfordii

2

3

1

0

1

1

0

2

1

1

1

?

?

2

?

0

0

“Quiché”

1

2

1

0

1

1

2

3

0

?

1

1

?

?

1

0

0

caballeroi

3

2

1

0

1

1

2

2

0

0

1

1

3

3

0

0

0

cf. fasciatus “Alto São 1 Francisco”

3

1

0

?

1

2

2

0

0

1

1

1

3

0

0

0


3

3

1

0

1

1

2

3

0

0

1

1

1

2

0

0

0

cocibolca

2

3

1

0

1

1

0

2

1

0

1

0

0

3

?

1

0

“Cubilhuitz”

4

3

1

0

1

1

2

3

0

0

1

1

0

3

0

0

0


1

2

1

2

?

1

2

3

1

0

1

0

0

1

1

0

0

dorioni

1

2

1

0

1

1

3

3

1

0

1

0

1

2

1

0

0

fasciatus

?

?

1

0

?

1

?

2

0

0

1

?

?

?

?

?

0

“Veracruz”

?

3

1

0

1

1

2

?

0

0

1

1

1

?

0

0

0

“Macal”

1

2

1

1

?

1

2

3

0

0

1

1

1

3

0

1

0

mexicanus

2

3

1

0

1

1

2

3

0

0

1

?

1

5

0

0

0

nasutus

2

2

1

0

1

?

?

2

1

0

1

?

?

3

0

?

0

nicaraguensis

3

?

1

0

1

1

2

2

1

0

1

0

1

1

1

0

0

“Ocotal”

1

3

1

0

1

?

2

3

0

0

?

1

2

3

?

0

0

“Costa Rica”

?

?

1

1

1

1

?

?

?

0

1

0

?

?

0

0

0

orthodus

1

2

1

2

?

0

1

1

1

0

1

0

1

1

0

0

0

panamensis

1

3

1

?

1

1

0

?

?

0

1

1

1

?

0

1

1

“Petén”

?

3

1

0

1

1

2

3

0

1

1

1

1

?

0

0

0

“Rioverde”

?

3

1

0

1

1

2

4

0

0

1

1

4

3

0

0

0

“Tamazulapan”

2

3

1

0

1

1

2

3

1

0

1

1

1

3

0

0

0

“Tamiahua”

2

3

1

0

2

1

2

3

0

0

1

1

1

2

0

0

0

“Tehuacán”

1

3

1

0

1

1

2

3

0

0

1

1

1

?

0

0

0


SCHMITTER-SOTO

between Central and South America, and that the faunal interchange made possible by the rise of the isthmus led to several Plio-Pleistocene reinvasions of Central American taxa back into northwestern South America. A Paleocene first closure of the Isthmus was already proposed by Myers (1966), and geological evidence for this view exists (e.g. Iturralde-Vinent 2006). The occurrence of A. “Acatlán” in a relatively basal position within its clade is interesting, The new species (Schmitter-Soto, unpubl. data) is endemic to central Mexico; its sister-group relationship to GuatemalanSoutheastern Mexican species, in turn sister to a clade including a Brazilian species, bespeaks again a probable “return to South America”. In contrast, other highland, microendemic, undescribed species occur in derived positions within their clades. These are A. “Macal”, from the Maya mountains of Belize, and A. “Ocotal”, from an endorheic lake in Chiapas which harbors at least one other endemic, Rocio ocotal (Schmitter-Soto 2007). Including cytogenetic data, available only for A. “Texas”, A. “Veracruz” (both 2n=50: Klinkhardt et al. 1995, d’Artola-Barceló2009), and A. fasciatus (2n=46 or 48: Pazza et al. 2007), does not alter the topology of the tree. Mirande (2010) coded lower chromosome numbers as plesiomorphic, but the prevailing view (e.g. Portela et al. 1988) is that this decrease in chromosome number is a derived trend. Esquivel-Bobadilla’s (2011) unrooted mtDNA tree shows one clade for northern Mexico (= A. “Texas”), another for cave forms (also in northern Mexico), and a third clade for central-southern forms, in the pattern B. caballeroi + (A. “Veracruz” + A. “Campeche”), which is congruent with the present hypothesis. More extended in material examined and choice of genetic markers is the phylogeny by Ornelas-García et al. (2008), based on mtDNA (CO1, cyt b, 16 S) and nuclear DNA (RAG1). These authors found A. fasciatus s. str. to be the sister taxon to all studied Middle American Astyanax, not part of the ingroup. Astyanax panamensis (as per my identification) is in their cladogram the following sister species to the rest, which consists of two large clades: excluding new species and localities not considered here (e.g., hypogean populations), the first group unites A. nasutus, A. nicaraguensis + A.bransfordii, A. “Macal”, and A. “Belize”; a second, more northern, group includes A. “Quiché”, A. aeneus, B. dorioni + A.”Petén”, A. altior, B. caballeroi, A. “Veracruz”, A. mexicanus, and A. “Texas”. As Degnan and Rosenberg (2006) observed, “because of the stochastic way in which lineages sort out during speciation, gene trees may differ in topology from each other and from species trees”. Nevertheless, the present morphological cladogram does show interesting congruence with the molecular proposal by Ornelas-García et al. (2008). Both cladograms find “Nicaraguan clades”, with A. nasutus and B. bransfordii as sister taxa, as well as a derived position for the northernmost species. However, the placing of many species, such as A. “Macal” and A. aeneus, is at variance between our hypotheses, even given the uncertainty caused by the large polytomy in the present strict-consensus proposal. As mentioned above, Mirande (2010) found A. “Texas” in the basal position of a South American Astyanax clade; nevertheless, it is difficult to compare his hypothesis to the one here proposed, given that there are no other taxa in common (except for B. bransfordii), since his aim was to recover the phylogenetic relationships of the Characidae, not to test any lower-level relationships. Mirande (2010) found species of Hyphessobrycon, Psellogramus, and Markiana in Astyanax-dominated clades; a broader sampling of Astyanax species and related genera is the still-missing bridge between his revision and the present contribution. Most species in this study are polymorphic for several characters; among the few taxa with no polymorphisms are B. caballeroi, B. dorioni, and A. cf. fasciatus “Ceará”. However, invoking the pervading phenomenon to preserve an “A. aeneus s. lat.”, at any level, does not seem useful: despite polymorphisms, all species in this study are diagnosable under a phylogenetic species concept (unpubl. data.). The fact that contact zones with genetic exchange are ubiquitous between species of Astyanax has been used by some authors (Strecker et al. 2004, Hausdorf et al. 2011) to sustain the view that all of these forms belong in just one species, A. fasciatus, under a strict biological species concept. However, these authors themselves (e.g. Strecker 2005) have endorsed a different view concerning the species of Cyprinodon in Lake Chichancanab, many of which not only share haplotypes, but are indistinguishable by most molecular markers and display a certain percentage of hybrids in nature. In the laboratory, the females of C. beltrani prefer the males of the larger species C. maya (Strecker 1996). Hybrid zones are also common among species of Cyprinidae in Europe (Machordom et al. 1990). The nominal A. emperador Eigenmann & Ogle 1907 and A. robustus Meek 1912 have been considered species of Bryconamericus (Meek 1914, Grey 1947, Román-Valencia 2002). Hence they were not included in this study.



125

Also omitted were García-Ornelas et al.’s (2008) “species 2” (Río Máquinas, Veracruz) and “species 3” (Montebello, Pacific Chiapas), because of unavailability of material for osteological study. The equivalence of Ornelas-García et al.’s (2008) “species 5” (Ciruelas to Chires, Panama), “species 6” (Ciruelas, Panama to Tempisque, Costa Rica), and “species 8” (Chagres, Panama) is not clear, since material from their exact localities was not available for study. The Panamanian area deserves further analysis, since several Astyanax species coexist in the region, as is true also for the complex Guatemalan Petén. My hypothesis does not recover a Bramocharax clade. Ornelas-García et al. (2008) also found Bramocharax to be polyphyletic. Rosen (1972) proposed that this genus, understood as composed by B. baileyi, B. bransfordii, and B. dorioni (the latter two, considered subspecies of B. bransfordii—found quite apart in the present phylogeny), originated in the Usumacinta system, with B. baileyi as the most primitive species. Valdez-Moreno (2005) found the same pattern, adding a new species from Chiapas (= B. “Ocotal”) as the most basal taxon. She claimed Bramocharax to be monophyletic, but the inclusion of the other Middle American Astyanax in the analysis proves otherwise. Moreover, the clustering together of former Bramocharax in Valdez-Moreno’s (2005) cladogram may be due to the large number of “trophic” characters used. These species did not appear together in one clade in the molecular hypothesis of Ornelas-García et al. (2008), their phenotypic resemblance being attributed to adaptive convergence, as every examined Bramocharax species was in a same clade with its respective sympatric Astyanax species. As for the grouping of B. bransfordii and Oligosarcus in Mirande’s (2010) hypothesis, the author himself acknowledged that his material was not sufficient to solve the problem, and he suggested that “[t]he inclusion of some Mesoamerican species of Astyanax with relatively high number of maxillary teeth, such as A. nasutus Meek and some morphologically conservative species of Bramocharax, such as B. baileyi Rosen, would be useful to test the monophyly and position of this clade” (interestingly, A. nasutus was found to be sister to B. bransfordii in the present hypothesis). The sole synapomorphy for his Bramocharax clade is the form of the epioccipital bridge, medially depressed. Valdez-Moreno (2005) included O. hepsetus in her study, and found it to lie in a group with species of Acestrorhynchus, far outside her Bramocharax-Astyanax clade, in fact in a position basal respective to Roeboides and Hyphessobrycon. An ontogenetic character state shift for A. mexicanus in “trophic” traits has been documented, namely a transition from unicuspid to multicuspid teeth (Trapani et al. 2005). Valdez-Moreno (1997) observed not just variation in the number of cusps, but also a confounding effect of erosion in older individuals. I have made little use of dental characters in this review, and none of cuspidization. The use of quantitative characters in cladistics can be controversial (Pimentel & Riggins 1987). Nevertheless, overlapping variability exists in “qualitative” characters as well (Kitching et al. 1998), and statistical coding procedures help formulate objective decisions (Rae 1998). On the other hand, Mirande (2010) and other authors have made substantial use of quantitative characters without any explicit criterion for defining states, aside from coding as “polymorphic” any species with overlapping variability. Ayache and Near (2009) state that morphological data are valuable not just for the discovery and description of new species, but also for building phylogenetic hypotheses, notwithstanding the fact that resolution and robustness of cladograms based on anatomical traits tend to be much lower than those using DNA-sequence data. In spite of the shortcomings, morphological datasets may underscore problematic areas of phylogenies deserving further study. Such is the present case.

Acknowledgments This work was done while on sabbatical stay at the University of Michigan Museum of Zoology, Division of Fishes, under a partial grant from the Mexican Consejo Nacional de Ciencia y Tecnología. I thank most warmly my hosts, Bill Fink and Jerry Smith, as well as the collection manager, Doug Nelson, who handled loans from ANSP, BMNH, ECOCH, FLMNH FMNH, GCRL, LACM, MNCN, MNHN, UANL, USM, USNM, ZMB, and ZMUC. Humberto Bahena processed the photographs. Janneth Padilla prepared the maps and all figures.


SCHMITTER-SOTO

References Archie, J. (1989) Homoplasy excess ratios: new indices for measuring levels of homoplasy in phylogenetic systematics and a critique of the ocnsistency index. Systematic Zoology, 38, 253–269. http://dx.doi.org/10.2307/2992286 Ayache, N.C. & Near, T.J. (2009) The utility of morphological data in resolving phylogenetic relationships of darters as exemplified with Etheostoma (Teleostei: Percidae). Bulletin of the Peabody Museum of Natural History, 50 (2), 327–346. http://dx.doi.org/10.3374/014.050.0203 Bussing, W.A. (1998) Peces de las aguas continentales de Costa Rica. Revista de Biología Tropical, 46, 1–468. Bermingham, E., & Martin, A.P. (1998) Comparative mtDNA phylogeography of neotropical freshwater fishes: testing shared history to infer the evolutionary landscape of lower Central America. Molecular Ecology, 7 (4), 499–517. http://dx.doi.org/10.1046/j.1365-294x.1998.00358.x Chakrabarty, P. & Albert, J. (2011) Not so fast. A new take on the Great American Biotic Interchange. In: Albert, J. & Reis, R.E. (Eds.), Historical Biogeography of Neotropical Freshwater Fishes. University of California Press, Berkeley, pp. 293–305. http://dx.doi.org/10.1525/california/9780520268685.003.0018 Crisp, M.D. & Chandler, G.T. (1996) Paraphyletic species. Telopea, 6 (4), 813–844. http://dx.doi.org/10.7751/telopea19963037 d’Artola Barceló, A.L. (2009) Aspectos citogenéticos de dos poblaciones de la sardina de agua dulce Astyanax aeneus (Pisces: Characidae). Unpubl. B.Sc. Diss., Universidad Juárez Autónoma de Tabasco, Villahermosa, Mexico. Degnan, J.H. & Rosenberg, N.A. (2006) Discordance of species trees with their most likely gene trees. PLoS Genetics, 2 (5), 762–768. http://dx.doi.org/10.1371/journal.pgen.0020068 Eigenmann, C.H. (1921) The American Characidae. Part 3. Memoirs of the Museum of Comparative Zoology, 43, 209–310. Esquivel-Bobadilla, S. (2011) Análisis genético de Astyanax mexicanus (Characidae, Teleostei, Pisces) de la vertiente atlántica de México usando microsatélites. Unpubl. M.Sc. Diss., Centro de Investigaciones Biológicas del Noroeste, La Paz, Mexico, 83 pp. Farris, J.S. (1989) The retention index and the rescaled consistency index. Cladistics, 5, 417–419. http://dx.doi.org/10.1111/j.1096-0031.1989.tb00573.x Felsenstein, J. (2009) PHYLIP (Phylogeny Inference Package) version 3.69. Department of Genome Sciences, University of Washington, Seattle. Greenfield, D.W. & Thomerson, J.E. (1997) Fishes of the Continental Waters of Belize. University Press of Florida, Gainesville, 311 pp. Grey, M. (1947) Catalogue of type specimens of species in Chicago Natural History Museum. Fieldiana: Zoology, 32 (3), 109–205. Hausdorf, B., Wilkens, H., & Strecker, U. (2011) Population genetic patterns revealed by microsatellite data challenge the mitochondrial DNA based taxonomy of Astyanax in Mexico (Characidae, Teleostei). Molecular Phylogenetics and Evolution, 60 (1), 89–97. http://dx.doi.org/10.1016/j.ympev.2011.03.009 Iturralde-Vinent, M.A. (2006) Meso-Cenozoic Caribbean paleogeography: implications for the historical biogeography of the region. International Geology Review, 48 (9), 791–827. http://dx.doi.org/10.2747/0020-6814.48.9.791 Kitching, I.J., Forey, P.L., Humphries, C.J. & Williams, D.M. (1998) Cladistics. The Theory and Practice of Parsimony Analysis. 2nd Ed. Oxford University Press, Oxford, 228 pp. Klinkhardt, M., Tesche, M. & Greven, H. (1995) Database of fish chromosomes. Westarb Wissenschaften, Heidelberg, 237 pp. Machordom, A., Berrebi, P., & Doadrio, I. (1990) Spanish barbel hybridization detected using enzymatic markers: Barbus meridionalis Risso × Barbus haasi Mertens (Osteichthyes, Cyprinidae). Aquatic Living Resources, 3 (04), 295–303. http://dx.doi.org/10.1051/alr:1990030 Maddison, W.P. & Maddison, D.R. (2011) Mesquite: A modular system for evolutionary analysis, version 2.75. Available from: http://mesquiteproject.org (accessed 27 November 2012) Meek, S.E. (1914) An annotated list of fishes known to occur in the fresh-waters of Costa Rica. Field Museum of Natural History Publications, Zoölogical Series, 10 (10), 101–134. http://dx.doi.org/10.5962/bhl.title.5576 Melo, F.A.G. de (2005) Revisão taxonômica do complexo de espécies Astyanax fasciatus (Cuvier, 1819) (Teleostei: Characiformes: Characidae). Ph.D. Diss., Museu Nacional, Universidade Federal do Rio de Janeiro, Brazil. Miller, R.R. (1986) Composition and derivation of the freshwater fish fauna of Mexico. Anales de la Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 30, 121–153. Miller, R.R., Minckley, W.L. & Norris, S.M. (2009) Peces Dulceacuícolas de México. Comisiòn Nacional para el Conocimiento y Uso de la Biodiversidad, ECOSUR, Sociedad Ictiológica Mexicana, and Desert Fishes Council, Mexico City, 559 pp. Mirande, J.M. (2010) Phylogeny of the family Characidae (Teleostei: Characiformes): from characters to taxonomy.



127

Neotropical Ichthyology, 8, 385–568. http://dx.doi.org/10.1590/S1679-62252010000300001 Myers, G.S. (1966) Derivation of the freshwater fish fauna of Central America. Copeia, 1966, 766–773. http://dx.doi.org/10.2307/1441405 Ornelas-García, C.P., Domínguez-Domínguez, O. & Doadrio, I. (2008) Evolutionary history of the fish genus Astyanax Baird & Girard (1854) (Actinopterygii, Characidae) in Mesoamerica reveals multiple morphological homoplasies. BMC Evolutionary Biology, 8, 340. http://dx.doi.org/10.1186/1471-2148-8-340 Pazza, R., Kavalco, K.F. & Bertollo, L.A.C. (2007) Chromosome polymorphism in Astyanax fasciatus (Teleostei, Characidae). 1. Karyotype analysis, Ag-NORs and mapping of the 18S and 5S ribosomal genes in sympatric karyotypes and their possible hybrid forms. Cytogenetic and Genomic Research, 112, 313–319. Pimentel, R.A. & Riggins, R. (1987) The nature of cladistic data. Cladistics, 3, 201–209. http://dx.doi.org/10.1111/j.1096-0031.1987.tb00508.x Portela, A.L.B.S., Galetti Jr., P.M. & Bertollo, L.A.C. (1988) Considerations on the chromosome evolution of Tetragonopterinae (Pisces: Characidae). Revista Brasileira de Genética, 11 (2), 307–316. Rae, T.C. (1998) The logical basis for the use of continuous characters in phylogenetic systematics. Cladistics, 14, 221–228. http://dx.doi.org/10.1111/j.1096-0031.1998.tb00335.x Román-Valencia, C. (2002) A systematic review of the species of the genus Bryconamericus (Teleostei: Characidae) from Central America. Revista de Biología Tropical, 50 (1), 173–192. Rosen, D.E. (1972) Origin of the characid fish genus Bramocharax and a description of a second, more primitive, species in Guatemala. American Museum Novitates, 2500, 1–21. Sabaj Pérez, M.H. (Ed.) (2012) Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an online reference. Vers. 3.0. Available from: http://www.asih.org/ (accessed 20 April 2014) Schmitter-Soto, J.J. (2007) Phylogeny of species formerly assigned to the genus Archocentrus (Perciformes: Cichlidae). Zootaxa 1618, 1–50. Schmitter-Soto, J.J., Valdez-Moreno, M.E. Rodiles-Hernández, R.& González-Díaz, A.A. (2008) Astyanax armandoi, a junior synonym of Astyanax aeneus (Teleostei: Characidae). Copeia, 2008 (2), 409–413. http://dx.doi.org/10.1643/CI-07-012 Simon, C. (1983) A new coding procedure for morphometric data with an example from periodical cicada wing veins. In: Felsenstein, J. (Ed.), Numerical Taxonomy. Springer, Berlin, 378–383. http://dx.doi.org/10.1007/978-3-642-69024-2_40 Strecker, U. (1996) Molekulargenetische und ethologische Untersuchungen zur Speziation eines Artenschwarmes der Gattung Cyprinodon (Cyprinodontidae, Teleostei). Ph.D. Diss., Univ. Hamburg. Shaker Verlag, Hamburg. Strecker, U. (2005) Description of a new species from Laguna Chichancanab, Yucatan, Mexico: Cyprinodon suavium (Pisces: Cyprinodontidae). Hydrobiologia 541, 107–115. http://dx.doi.org/10.1007/s10750-004-4821-3 Strecker, U., Faúndez, V.H. & Wilkens, H. (2004) Phylogeography of surface and cave Astyanax (Teleostei) from Central and North America based on cytochrome b sequence data. Molecular Phylogenetics and Evolution, 33 (2), 469–481. http://dx.doi.org/10.1016/j.ympev.2004.07.001 Taylor, W.R. & van Dyke, G.C. (1985) Revised procedures for staining and clearing small fishes and other vertebrates for bone and cartilage study. Cybium, 9, 107–119. Trapani, J., Yamamoto, Y. & Stock, D.W. (2005) Ontogenetic transition from unicuspid to multicuspid oral dentition in a teleost fish: Astyanax mexicanus, the Mexican tetra (Ostariophysi: Characidae). Zoological Journal of the Linnean Society, 145 (4), 523–538. http://dx.doi.org/10.1111/j.1096-3642.2005.00193.x Valdez-Moreno, M.E. (1997) Estudio comparativo osteológico del género Astyanax en diversas cuencas de México. Unpubl. M.Sc. Diss., Universidad Nacional Autónoma de México, Mexico City. Valdez-Moreno, M.E. (2005) Osteología craneal del subgénero Catemaco género Bramocharax (Teleostei: Characidae): relaciones filogenéticas y biogeografía. Unpubl. Ph.D. Diss., Universidad Autónoma de Nuevo León, Monterrey, Mexico. Zanata, A.M. & Vari, R.P. (2005) The family Alestidae (Ostariophysi, Characiformes): a phylogenetic hypothesis of a transAtlantic clade. Zoological Journal of the Linnean Society, 145 (1), 1–144. http://dx.doi.org/10.1111/j.1096-3642.2005.00183.x


SCHMITTER-SOTO

APPENDIX 1. Material examined (in bold, with cleared-and-stained or skeletonised specimens). Order by country and locality, then collection codon and catalog number. Institutional codons follow Sabaj-Pérez (2012). Further data available from the author on request. Astyanax “Acatlán”: UMMZ 203317, Mexico, Río Acatlán; UMMZ 191698, Mexico, Río Jía. Astyanax “Bacalar”: ECOCH 1764, UMMZ 196478, 246454, Mexico, Laguna Bacalar; UMMZ 202874, Belize, Gabourel Creek; UMMZ 246840, Belize, River Sittie; ECOCH 1976, Mexico, Laguna Encantada; UMMZ 196540, Mexico, pool near Tulum; UMMZ 210875, Mexico, Río Hondo; UMMZ 194103, Guatemala, Río Mopán; FLMNH 101171, Mexico, Tulum. Astyanax “Belize”: MNHN 5224-5225 (ST of Tetragonopterus belizianus), Belize, Mullins River; UMMZ 246831, Belize, Moho River; BMNH 1861.8.12.20-21 (ST of T. brevimanus), MRAC 7057 (ST of T. brevimanus), ZMB 6801 (ST of A. panamensis), Guatemala, Lake Izabal; UMMZ 194018, Guatemala, Motagua; UMMZ 194002, Guatemala, Río Agua Fría; UF 115561, Guatemala, Río Dulce; UMMZ 197303, Guatemala, Río Trincheras; USM 34095, Honduras, Aguán; USM 35490, Honduras, Cangrejal; USM 36032, 36056, 36066, Honduras, Chamelecón; UF, Honduras, Colón; USM 31071, Honduras, La Ceiba; USM 35611, Honduras, Lancetilla; UMMZ 155869, Honduras, Río Celán; LACM 32458-1, USM 36370, 36408, Honduras, Río Coco; UMMZ 228667, Honduras, Río Jutiapa; UMMZ 199524, Honduras, Río Patuca; USM 34131, 36057, Honduras, Río Sico; UMMZ 155868, Honduras, Río Ulúa; USM 31910, Honduras, Tulián. Astyanax “Campeche”: BMNH ex 1857.7.31.9 (syntypes of T. angustifrons), “Mexico”; UMMZ 143326, Guatemala, Arroyo Subín; UMMZ 143428, Guatemala, Río San Pedro; UMMZ 102209, UMMZ 196571, Mexico, Río Champotón; UMMZ 196625, Mexico, Río Mamantel; UMMZ 246448, Mexico, Río Ulumán; UMMZ 64475, Mexico, aguada at Tuxpeña; UMMZ 187429, Mexico, Zohlaguna. Astyanax “Costa Rica”: ZMUC 948, ZMB 9197, ZMUC 947, ZMUC 955, ZMUC 956 (ST of T. orstedii), Costa Rica/ Nicaragua, Río San Juan; UMMZ 243884, Costa Rica, Corobicí; LACM 8311, Costa Rica, Divia; FMNH 6257 (HT of A. regani), GCRL 5095, Costa Rica, Las Cañas; LACM 4831, UMMZ 194212, Costa Rica, Puntarenas; UMMZ 245906, Costa Rica, Quebrada Blanca; UMMZ 245887, Costa Rica, Río Blanco; UMMZ 138248, Costa Rica, Siquirres; UMMZ 194221, Costa Rica, Tárraba; UMMZ 159153, 243890, Costa Rica, Tempisque; UMMZ 145677, Panama, Chiriquí. Astyanax “Cubilhuitz”: UMMZ 188007, Guatemala, Río Dolores. Astyanax “Macal”: UMMZ 178599, Belize, River Macal. Astyanax “Ocotal”: UMMZ 171139, Mexico, Laguna Ocotal. Astyanax “Petén”: BMNH 1864.1.26.374 (ST), Guatemala, Lake Petén Itzá ; UMMZ 190975, Guatemala, Arroyo El Chorro; UMMZ 143332, Guatemala, Arroyo Jolomax; UMMZ 143441, Guatemala, Eckibix; UMMZ 143433, Guatemala, Lago Petén Itzá; UMMZ 143424, Guatemala, Laguna Perdida; UMMZ 97877, Guatemala, Uaxactún; UMMZ 186378, Mexico, Río Chiapa. Astyanax “Quiché”: BMNH 1864.1.26.388, 1864.1.24.177 (ST of T. brevimanus), Guatemala, Río San Gerónimo; MNHN 5219 (ST of T. cobanensis, 6 dig), Guatemala, Cobán; LACM 37765-1, Guatemala, Ixcán; UMMZ 131142, Guatemala, Río Copón; UMMZ 193886, Guatemala, Río Sachichá; UMMZ 173731, Mexico, Cintalapa; UMMZ 167714, Mexico, Río Grande de Comitán; UMMZ 161769, Mexico, Río Santa Cruz. Astyanax “Rioverde”: UMMZ 192510, 172194, Mexico, “Rioverde”; UMMZ 193447, Mexico, Río Santa María. Astyanax “Tamazulapan”: TNHC 25027, TU 185676, UANL 14306, 14327, 22296, UMMZ 234194, USNM 357728, Mexico, Ojo de Agua de Tamazulapan. Astyanax “Tamiahua”: UMMZ 97362, Mexico, Río Cucharas; UMMZ 167489, Mexico, Río Nautla. Astyanax “Tehuacán”: UMMZ 198853, Mexico, Río Salado. Astyanax “Texas”: BMNH 1883.12.14.107 (ST of A. argentatus), USA, Río Nueces; UMMZ 182081, Mexico, Cuatro Ciénegas; UMMZ 186469, Mexico, Río Apodaca; UMMZ 192476 (161 spms., 8 dig), Mexico, Río Limón; UMMZ 179171, Mexico, Río Salado; UMMZ 211059, Mexico, Durango; UMMZ 170107, USA, Rio Pecos. Astyanax “Veracruz”: MNHN 5223 (ST of T. finitimus), Mexico, near Orizaba; UMMZ 183900, Mexico, Cocolapa; UMMZ 215480 (PT of A. armandoi), Mexico, Gregorio Sánchez Magaña; UMMZ 196382, Mexico, laguna near Tierra Blanca ; UMMZ 191727, Mexico, near Palenque; UMMZ 97335, Mexico, Río Chachalacas; ANSP 15598-608, 32271, 32272 (ST of T. streetsii), Mexico, Río Coatzacoalcos; UMMZ 184761, Mexico, Río Jaltepec; UMMZ 97336, Mexico, Río Paso San Juan; UMMZ 184703, Mexico, Río Teapa; BMNH 1905.12.6.20, USNM 127094 (ST of T. macrophthalmus), Mexico, Río Tonto. Astyanax aeneus: BMNH 1907.4.10.3, BMNH 1860.6.17.41-42, Mexico, Oaxaca; UMMZ 197102, Guatemala, creek near Taxisco; UMMZ 190523, Guatemala, ditches near Escuintla; BMNH 1865.4.29.43-44 (syntypes of T. microphthalmus), BMNH 1865.4.29.45-50 (syntypes of T. humilis), Guatemala, Lake Amatitlán; UF 115560, UF 115933, Guatemala, Escuintla; USM 36089, Honduras, Goascorán; UMMZ 144614, USM 33957, Honduras, Río Nacaome; UMMZ 144617, UMMZ 144618, UMMZ 144621, Honduras, Río Choluteca; UMMZ 191719, Mexico, Huixtla; UMMZ 161510, México, pond in Tehuantepec; UMMZ 168919, Mexico, Río Cacaluta; UMMZ 108596, UMMZ 108597, UMMZ 178490, UMMZ 181829, México, Río Papagayo; UMMZ 184737, Mexico, Río Tapanatepec; UMMZ 178568, Mexico, Río Tequisistlán; UMMZ 184801, Mexico, Río Arenas. Astyanax altior: UMMZ 102144 (holotype), UMMZ 102145 (paratypes), Mexico, Progreso; ECOCH 2988, Mexico, cenote near Celestún; ECOCH 2955, Mexico, cenote near Chunchucmil; UMMZ 196550, Mexico, cenote at Dzibilchaltún;



129

UMMZ 196564, Mexico, cenote near Sisal. Astyanax atratoensis: UMMZ 61965, 160232, Colombia, Truando. Astyanax bimaculatus: UMMZ 206863, Paraguay, Arroyo Tobatiry. Astyanax cf. fasciatus “Alto São Francisco”: UMMZ 216281, Brazil, upper Río São Francisco. Astyanax cf. fasciatus “Ceará”: UMMZ 147331, Brazil, Riacho do Constantino Astyanax cf. fasciatus “das Velhas”: UMMZ 216372 (117 spms., 1 dig), Brazil, Río das Velhas. Astyanax cocibolca: LACM 56648-1 (HT), 56648 (PT), UMIM 3601, UMMZ 209838, Nicaragua, Lake Nicaragua. Astyanax fasciatus: MNHN 8653 (ST), MNHN 9896 (ST), Brazil, Río São Francisco. Astyanax mexicanus: ZMUC 941, MZUT 149, ZMUC 942 (ST), “lake near Mexico”; UMMZ 169835, Mexico, Barranco Capire; MNHN 5194 (ST of T. fulgens), MNHN 5191 (ST of T. nitidus), Mexico, near Cuernavaca; UMMZ 178410, Mexico, Río Aguililla; UMSNH uncat., Mexico, Río Cupatitzio; UMMZ 160764, Mexico, Colima. Astyanax nasutus: FMNH 5909 (HT), 5908 (PT), Nicaragua, Lake Managua. Astyanax nicaraguensis: USNM 55653 (HT), USNM 55657 (PT), “Nicaragua”; UMMZ 166469, Costa Rica, Laguna del Misterio; UMMZ 162475 (PT of A. aeneus var. costaricensis), Costa Rica, Río Parismina; USNM 45381, Nicaragua, Greytown; USNM 44322, Nicaragua, Río Escondido; UMMZ 165772, Nicaragua, Matagalpa; USNM 44192, Nicaragua, San Carlos; UMMZ 145686, Panama, Río Sixaola. Astyanax orthodus: UMMZ 160225, Colombia, Truando. Astyanax panamensis: BMNH 1864.1.26.415 (ST), “Pacific Panama”; GCRL 13409, Panama, Calobre ; FLMNH 16696, Panama, Canal Zone; LACM 56197-2, Panama, Cárdenas; UF 12973, Panama, Chepo; UMMZ 61263, Panama, San Blas; UF 19666, Panama, Tonosí. Bramocharax baileyi: AMNH 30197 (HT), Guatemala, Río San Simón; UMMZ 190763, Guatemala, near Río Canilla. Bramocharax bransfordii: USNM 16885 (ST), FMNH 5922 (HT of B. elongatus), UMMZ 180608, 16885 (PT of B. elongatus), Nicaragua, Lake Nicaragua. Bramocharax caballeroi: UANL 5681 (HT), UMMZ 184539, Mexico, Lake Catemaco. Bramocharax dorioni: AMNH 29411 (HT), Guatemala, Río Semococh; UMMZ 187944, Guatemala, Río de la Pasión; UMMZ 193918, Guatemala, Río San Simón.. Brycon guatemalensis: UMMZ ex 246840, Belize, Sittie; UMMZ 190656, Guatemala, Livingston. Hyphessobrycon compressus: ECOCH 1449, Mexico, Arroyo Huay Pix; UANL 5784, 5849, after Valdez-Moreno (2005). Roeboides guatemalensis: UANL 1696, after Valdez-Moreno (2005).


SCHMITTER-SOTO