Crustacea: Amphipoda: Caprellidea - Universidad de Sevilla

J  N H, 2003, 37, 1059–1084

Revision of the genus Deutella (Crustacea: Amphipoda: Caprellidea) with description of a new species, redescription of Deutella venenosa Mayer, 1890 and a key to the species of Deutella J. M. GUERRA-GARCIÁ Laboratorio de Biologıá Marina, Departamento de Fisiologıá y Biologıá Animal, Facultad de Biologıá, Universidad de Sevilla, Apdo. 1095, E-41080 Sevilla, Spain; e-mail: [email protected] (Accepted 4 October 2001) The genus Deutella is reviewed and a key to the species is given. A new species of Deutella is described from Isla Margarita, Venezuela. Full description and illustrations are given for the adult male and female. Diagnostic features of this species are: body dorsally smooth, flagellum of antenna 1 with 14 articles in males and 10 in females, setal formula of the mandibular palp 1-9-1, molar flake present, propodus palm of gnathopod 1 with a pair of grasping spines, male abdominal appendages two-articulate. Deutella venenosa Mayer, 1890 is redescribed based on the material newly collected from Coquimbo, Chile. This species is recorded for the first time since the original description by Mayer (1890). The species Luconacia vemae McCain and Gray, 1971 is transferred to the genus Deutella. K: Crustacea, Amphipoda, Caprellidea, Deutella, taxonomy.

Introduction The genus Deutella was established by Mayer (1890). So far, six species of this genus have been described: Deutella aspiducha Gable and Lazo-Wasem, 1987, D. californica Mayer, 1890, D. incerta (Mayer, 1903), D. mayeri Stebbing, 1895, D. schieckei Cavedini, 1981 and D. venenosa Mayer, 1890. In the present paper, a new species Deutella margaritae is described and Luconacia vemae McCain and Gray, 1971 is transferred to the genus Deutella. Consequently, the genus Deutella is presently composed of eight species, which are reviewed and illustrated in this paper. During a short stay at the Universidad Cato´lica del Norte, Coquimbo, Chile, the author collected abundant material of Deutella venenosa Mayer, 1890, the first record for the species since the original description. The species is fully redescribed and illustrated in the present paper. As a result of consulting material of the genus Deutella from the collections of the National Museum of Natural History, Smithsonian Institution, Washington, DC, an undescribed species of Deutella collected from Isla Margarita, Venezuela in 1964 was found. Detailed examination Journal of Natural History ISSN 0022-2933 print/ISSN 1464-5262 online © 2003 Taylor & Francis Ltd http://www.tandf.co.uk/journals DOI: 10.1080/00222930110104267

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revealed that these specimens of Deutella belonged to a new species, described as Deutella margaritae in the present paper. Figures of all Deutella species and a key for easy identification have also been included based on careful examination of type and non-type material from Museums. The location of the specimens of Deutella examined is indicated by the following abbreviations: AMNH, American Museum of Natural History, New York, USA; CMNC, Canadian Museum of Nature, Canada; MCSN, Museo Civico di Storia Naturale di Verona, Italy; MCZ, Museum of Comparative Zoology, Harvard University, MA, USA; MNHN, Museo Nacional de Historia Natural de Santiago, Chile; USNM, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA. Systematics Family PARIAMBIDAE Laubitz, 1993 Diagnosis. Antenna 2 flagellum two-articulate. Mandible molar present, palp three-articulate; setal formula 1-x-1 or one apical setae; incisor five-toothed; left lacinia mobilis five-toothed; right lacinia serrate or broadly three-toothed. Lower lip with inner lobes well demarcated. Maxilla 1 with six spiniform setae on outer plate. Maxilliped outer plate larger than inner; inner plate truncate with few apical setae. Gnathopod 1 propodus triangular to slender. Gills on pereonite 3 and 4. Pereopod 3 and 4 greatly reduced; pereopod 5 weaker than 6 and 7. Genus Deutella Mayer, 1890 Diagnosis. Flagellum of antenna 2 with two articles, swimming setae absent. Mandibular palp three-articulate; setal formula for distal article 1-x-1; molar present. Outer lobe of maxilliped longer than inner lobe. Pereopod 5 with six articles. Male abdomen with pair of appendages and pair of setose lobes. Type species. Deutella californica Mayer, 1890. Deutella aspiducha Gable and Lazo-Wasem, 1987 (figure 1) Deutella aspiducha Gable and Lazo-Wasem, 1987: 629–639, figures 1–3.

Material examined. Male holotype, USNM 195178, Little River Cave, Bermuda, 8 May 1982; female allotype, USNM 195177, Little River Cave, Bermuda, 8 May 1982. Distribution. Only known from the type locality, Bermuda, USA. Ecology. Among hydroids, shallow subtidal. Remarks. Deutella aspiducha was recently described by Gable and Lazo-Wasem (1987). The most striking differences from all other Deutella species is the size and the shape of the last two articles (propodus and dactylus) of pereopod 5. Furthermore, this species lacks a triangular projection on the penultimate article of the palp of the maxilliped. Nevertheless, Gable and Lazo-Wasem (1987) classified this species as Deutella on the basis of the following characters: structure and proportions of the antennae, most of its mouthpart morphology, the various pereonite projections, the delineation of the palm of gnathopod 2 in males, the strong anterior insertion of gnathopod 2 on pereonite 2, the shape, length and insertion

Revision of the genus Deutella

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F. 1. Deutella aspiducha Gable and Lazo-Wasem, 1987. Lateral view and detail of gnathopod 2. (A, C ) Male; (B, D) female. Scale bars: (A, B) 1 mm; (C, D) 0.3 mm.

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patterns of pereopods 3 and 4, and the structure of the male abdomen. Even the smallest individuals of D. aspiducha show short dorsal spines on the cephalon and pereonite 2 (Gable and Lazo-Wasem, 1987). This species is, so far, endemic to Bermuda. Deutella californica Mayer, 1890 (figure 2) Deutella californica Mayer, 1890: 27–28, pl. 1, figures 3, 4, pl. 3, figures 15, 16, pl. 5, figure 18; Dougherty and Steinberg, 1953: 44; 1954: 169, 171, figure 82f; Steinberg and Dougherty, 1957: 279–281, figures 15, 21–23, 28; McCain, 1968: 54, figure 52; McCain and Steinberg, 1970: 48; Laubitz, 1970: 16–18, figures 3, 26.

Material examined. Seven males, three females, one juvenile, syntypes MCZ 1059, Cape Mendocino, California, 5 July 1860; three males, one female (non-types), CMNC 1989-0944, Tillamook, Oregon, 16 August 1966; one male (non-type), USNM 42667 Point Mugu, California, 5 December 1962. Distribution. Type locality: Cape Mendocino, California. Other localities: Monterey Bay and Mussel Point, California; San Juan area, Washington; Oregon, Washington and Vancouver Island; Juan de Fuca Strait, B.C., southern Prince William Sound, Alaska. Ecology. Collected from Obelia dichotoma (Linnaeus, 1758) on caparace and legs of Loxorhynchus grandis Stimpson, 1857 (ca 10–15 m depth). Also collected from flat fine sand, sandstone and shale bedrock. Remarks. The shape of the gnathopod 2 propodus in males is the best characteristic to differentiate easily this species among the remaining species of Deutella. Deutella californica was originally described by Mayer from Cape Mendocino, California and later reported from Monterey Bay by Dougherty and Steinberg (1953). Steinberg and Dougherty (1957) reported it as occurring at ‘probably Port Arkansas, Texas’. As has been pointed out by McCain (1968) and Laubitz (1970), the Texas locality record for this species is very doubtful; it is probable that Deutella californica is endemic to the Pacific. Deutella incerta (Mayer, 1903) (figure 3) Protellopsis stebbingii Kunkel, 1910: 111–113, figure 43. Deutella incerta; Steinberg and Dougherty, 1957: 281, 285–286; Gable and Lazo-Wasem, 1987: 635–636, figure 4. Luconacia incerta; Mayer, 1903: 49–50, pl. 2, figures 11–14; pl. 6, figures 73–75; pl. 9, figures 21, 40, 57; McCain, 1968: 53–54, 68–72, figures 33–35; McCain and Steinberg, 1970: 53.

Material examined. One male, one female (types), USNM 026001, three females (paratypes), USNM 123527, 213–234 m depth, 10 February 1934; one male, one female (non-types), USNM 42667, Gulf of Mexico. Distribution. Type locality: off Mobile Bay, Alabama, 29°24∞N, 88°04W. Other localities: Bermuda, east coast of North America from Woods Hole, Massachusetts to Straits of Florida; Gulf of Mexico from Cedar Keys, Florida to Yucatan; Virgin Islands; Barbuda; Barbados; Isla de Margarita, Aruba. Ecology. This species has been collected on mangrove roots, Sargassum, Thalassia, sponges, hydroids, alcyonarians, ascidians and it has occasionally been taken in plankton tows. Remarks. Deutella incerta is widely distributed in the temperate and tropical


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F. 2. Deutella californica Mayer, 1890. Lateral view and detail of gnathopod 2. (A, C ) Male; (B, D) female. Scale bars: 1 mm.

areas of the western North Atlantic (McCain, 1968) and seems to be one of the most commonly encountered caprellids in Bermuda (Gable and Lazo-Wasem, 1987). Steinberg and Dougherty (1957) synonymized Luconacia of Mayer (1903) with Deutella, transferring Luconacia incerta Mayer, 1903 to the genus Deutella. McCain

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F. 3. Deutella incerta (Mayer, 1903). Lateral view and detail of gnathopod 2. (A, C ) Male; (B, D) female. Scale bars: 1 mm.

(1968) re-established Luconacia on the basis of the following differences: apical setae are present on the terminal article of the maxilliped palp and a projection is present on the penultimate article in Deutella, while both are lacking in Luconacia incerta; the terminal article of the mandibular palp in Deutella has no knobs and in Luconacia incerta there is a knob; in Deutella the tip of the male abdominal appendage is


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without papillae and fringed or not fringed, and in Luconacia incerta both papillae and fringes are present; the female abdomen in Deutella is lobed and in Luconacia incerta it is not; pereopod 5 is inserted posteriorly on pereonite 5 in Deutella, but in Luconacia incerta at mid-length. The discovery of Deutella aspiducha by Gable and Lazo-Wasem (1987) provided these authors with a transitional form that allowed them to re-unite Deutella and Luconacia. Curiously, Gable and Lazo-Wasem (1987) overlooked the existence of the species Luconacia vemae McCain and Gray, 1971. This species had been described in a revision of the Caprellidea from the Antarctic and Subantarctic by McCain and Gray (1971). However, the differences between Luconacia vemae and Deutella incerta further support the combination of the two genera. The abdominal appendages of L. vemae do not bear as complete a fringe of small teeth around the papillae as in D. incerta. Furthermore, the knobs on the terminal article of the mandibular palp, one of the most important characteristics used by McCain (1968) to differentiate between Deutella (knobs absent) and Luconacia (knobs present), are not present in L. vemae. Therefore, the species Luconacia vemae must be transferred, as Luconacia incerta, to the genus Deutella with the genus Luconacia becoming a synonym. Deutella margaritae new species (figures 4–7) Material examined. Holotype male ( USNM 1000206), allotype female ( USNM 1000207) and paratypes (three males, seven females, USNM 1000208), 11 January 1964, Venezuela. Type locality. Puente de la Restinga, Isla Margarita, Venezuela. Etymology. Deutella margaritae is dedicated to Isla Margarita, the beautiful place where the specimens were collected. Ecology. The specimens were collected in boulders near Rhizophora. Description Holotype male Body length. 7.80 mm. Lateral view (figure 4A). Body dorsally smooth. Anterolateral margin of pereonites 2, 3 and 4 with triangular projection. Pereonites 3 and 4 subequal. Pereonite 5 the longest. Gills (figure 4A). Elongate, length about 3.5 times width. Mouthparts. Upper lip (figure 5F ) symmetrically bilobed, smooth. Mandibles (figure 5A, B) with three-articulate palp; distal article of palp with knobs and a setal formula 1-9-1; mandibular molar process strong, bordered by teeth; left mandible with incisor five-toothed, lacinia mobilis four-toothed followed by a row of three serrate spines; incisor of right mandible divided into five teeth, lacinia mobilis deeply serrate followed by a row of two serrate spines; molar flake present, serrate distally and carrying minute setulae. Lower lip (figure 5G) with inner lobes well demarcated; outer lobe without setae. Maxilla 1 (figure 5D) outer lobe carrying five spine-like setae; distal article of the palp with four distal spine-like setae and one seta medially. Maxilla 2 (figure 5C ) outer lobe with three setae distally; inner lobe rectangular, two-thirds of outer lobe in length, provided with four setae. Maxilliped (figure 5E) inner plate small and elongate with one tooth, three simple setae distally and a plumose seta laterally; outer plate about 2.5 times as long as inner plate, with four

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F. 4. Deutella margaritae new species. Lateral view. (A) Male; (B) female. Scale bar: 1 mm.

setae; penultimate article of palp without distal projection; dactylus wide, with rows of setulae. Antennae. Antenna 1 (figure 6A) about half of body length; peduncle not setose; flagellum 14-articulate. Antenna 2 (figure 6B) about two-thirds of antenna 1 length; proximal article of peduncle with an acute projection; flagellum two-articulate; peduncle and flagellum scarcely setose. Gnathopods. Gnathopod 1 (figure 6C ) basis as long as ischium to carpus combined; propodus elongate with a pair of grasping spines; grasping margin of propodus palm and dactylus smooth. Gnathopod 2 (figure 6D) inserted on the anterior half of pereonite 2; basis as long as pereonite 2; ischium rectangular; merus rounded; carpus short and triangular; propodus somewhat longer than basis; palm provided with a rectangular projection proximally, provided with a small tooth and small distal projection; dactylus thickened medially with three fine setae. Pereopods. Pereopods 3 and 4 (figure 7A, B) with two articles; distal article carrying six setae; pereopods 5–7 missing; insertion of pereopod 5 posteriorly in pereonite 5. Penes (figure 7C, D). Large, length 2.5 times width.


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F. 5. Deutella margaritae new species. Male. (A) Left mandible; (B) right mandible; (C ) maxilla 2; (D) maxilla 1; (E) maxilliped; (F ) upper lip; (G) lower lip. Scale bars: 0.1 mm.

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F. 6. Deutella margaritae new species. (A–D) Male. (A) antenna 1; (B) antenna 2; (C ) gnathopod 1; (D) gnathopod 2. (E) Female gnathopod 2. Scale bars: (A, B) 0.5 mm; (C ) 0.3 mm; (D, E) 0.5 mm.


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F. 7. Deutella margaritae new species. (A–D) Male. (A) Pereopod 3; (B) pereopod 4; (C ) abdomen (ventral view); (D) abdomen ( lateral view). (E) Female abdomen (ventral view). Scale bars: (A, B) 0.2 mm; (C–E) 0.1 mm.

Abdomen (figure 7C, D). Abdomen with a pair of two-articulate appendages, a pair of lateral lobes and a single dorsal lobe. Distal article of appendages minutely toothed, carrying small setulae distally. Allotype female Body length 6.20 mm. Flagellum of antenna 1 with 10 articles (figure 4B). Propodus of gnathopod 2 (figure 6E) lacking the rectangular projection present in males; dactylus not thickened medially, without setae. First pair of oostegites scarcely

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setose; second pair smooth (figure 4B). Abdomen (figure 7E) without appendages; lateral lobes not setose and single dorsal lobe provided with two plumose setae. Remarks Deutella margaritae nov. sp. posses two characteristics unique in the genus Deutella: male abdominal appendages two-articulate and a left lacinia mobilis fourtoothed. In connection with other morphological characters, D. margaritae resembles D. mayeri and D. schieckei in the absence of dorsal projections. Nevertheless, the mandibular palp is very different; there are knobs in D. margaritae and the setal formula is 1-9-1 while D. mayeri and D. schieckei lack knobs and have only one or two setae distally on the terminal article of the mandibular palp. Deutella mayeri Stebbing, 1895 (figure 8) Deutella mayeri Stebbing, 1895: 400–402, pl. 15a; Mayer, 1903: 44–45; McCain, 1968: 54–57, figures 25–26, 52; McCain and Steinberg, 1970: 48.

Material examined. One male, one female (non-types) USNM 225512, 18 m depth, Gulf of Mexico, 25°45∞58◊N, 82°01∞08◊W. Distribution. Type locality: Antigua. Other localities: Bahıá Fosforescente, Puerto Rico. Ecology. Unknown Remarks. Deutella mayeri was first described by Stebbing (1895). McCain (1968) redescribed and illustrated the species in detail. The gnathopod 2 of males is very characteristic. It has a triangular process proximally, provided with a grasping spine. The striking gnathopod can be used to distinguish this species easily from the remaining species of Deutella. Deutella schieckei Cavedini, 1981 (figure 9) Deutella schieckei Cavedini, 1981: 515, figure 9; Krapp-Schickel, 1993: 794, 796: figure 542.

Material examined. Holotype male, MCSNV 606-607, 2 June 1974, Sardinia, Capo Caccia, Italy. Distribution. Only known from the type locality, Sardinia, Capo Caccia, Italy. Ecology. Interstitial ( Krapp-Schickel, 1993). Remarks. The presence of the genus Deutella in Mediterranean waters provided the Mediterranean fauna with a very interesting biogeographical element because of the affinity with species from the Caribbean fauna. McCain’s (1968) suggestion that the removal of D. mayeri from the genus Deutella would make it an exclusive Pacific Ocean genus and Luconacia, then, an exclusive Atlantic Ocean genus, loses foundation for further consideration with Cavedini’s (1981) discovery of the Mediterranean D. schieckei (Gable and Lazo-Wasem, 1987). Deutella vemae (McCain and Gray, 1971) (figure 10) Luconacia vemae McCain and Gray, 1971: 123, figure 8.

Material examined. Holotype male, AMNH 13132, 81 m depth, 23 May 1961, 41°57∞S, 59°03∞W. Paratypes: two males, one female, AMNH 13133 collected together


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F. 8. Deutella mayeri Stebbing, 1895. Lateral view and detail of gnathopod 2. (A, C ) Male; (B, D) female. Scale bars: (A, B) 1 mm; (C, D) 0.3 mm.

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F. 9. Deutella schieckei Cavedini, 1981. Lateral view and detail of gnathopod 2. (A, C ) Male; (B, D) female. Scale bars: (A, B) 1 mm; (C, D) 0.3 mm.

with the holotype; one female, USNM 123749, 92–101 m depth, 5 February 1964, 52°56∞S, 75°00∞W. Distribution. Type locality 41°57∞S, 59°03∞N. Other localities: off coast of Argentina and Southern Chile. Ecology. Depth range 24–101 m. Remarks (as for Deutella incerta). Deutella venenosa Mayer, 1890 (figures 11–15) Deutella venenosa Mayer, 1890: 28, pl. 1, figures 5–9; pl. 3, figures 7–14; pl. 5, figures 19–21; pl. 6, figures 11–24.


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F. 10. Deutella vemae (McCain and Gray, 1971). Lateral view and detail of gnathopod 2. (A, C ) Male; (B, D) female. Scale bars: 1 mm.

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F. 11. Deutella venenosa Mayer, 1890. Lateral view. (A) Male; (B) female. Scale bar: 1 mm.


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F. 12. Deutella venenosa Mayer, 1890. Male. (A) Right mandible; (B) left mandible; (C ) maxilliped; (D) upper lip; (E) lower lip; (F ) maxilla 1; (G) maxilla 2. Scale bars: 0.1 mm.

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F. 13. Deutella venenosa Mayer, 1890. (A–D) Male. (A) Antenna 1; (B) antenna 2; (C ) gnathopod 1; (D) gnathopod 2. (E) Female gnathopod 2. Scale bars: (A, D) 1 mm; (B) 0.3 mm; (C ) 0.2 mm; (E) 0.5 mm.


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F. 14. Deutella venenosa Mayer, 1890. (A–F ) Male. (A) Pereopod 3; (B) pereopod 4; (C ) pereopod 5; (D) pereopod 6; (E) pereopod 7; (F ) abdomen (ventral view). (G) Female abdomen (ventral view). Scale bars: (A, B) 0.2 mm; (C–E) 1 mm; (F, G) 0.1 mm.

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F. 15. Deutella venenosa Mayer, 1890. Ontogenetic development. (A) Male lateral and dorsal view; (B) male gnathopod 2. Scale bars: (A) 1 mm; (B) 0.3 mm.

Material examined. Two hundred and four males, 73 premature females, 257 mature females, 73 juveniles, 0–5 m depth, November to December 2000, Coquimbo, Chile. Male ‘a’, female ‘b’ and several other specimens have been deposited in the


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Museo Nacional de Historia Natural de Santiago de Chile, MNHN AMPH No. 11312. Distribution. Only known from the type locality, Coquimbo, Chile. Ecology. Attached to buoys of seaweed cultures, mainly on hydroids, and bryozoans such as Bugula neritina (Linnaeus, 1758). Also under rocks in the intertidal zone clinging to the hydroid Obelia dichotoma (Linnaeus, 1758). Redescription Male ‘a’ Colour of live specimen. Light brown with dark spots. Body length. 5.71 mm. Lateral view (figure 11A). Head provided with a dorsal, anteriorly directed acute projection. Pereonite 1 with a projection medially. Pereonite 2 with three dorsal projections, one small anteriorly, one acute at the middle and a large rounded one posteriorly; a pair of lateral acute projections anteriorly directed. Pereonites 3–7 dorsally smooth, except pereonites 3 and 4 with humps. Side plates of pereonites 3, 4 and 5 projecting ventrolaterally, with margins distinctly crenulate. Gills (figure 11A). Oval, length about twice width. Mouthparts. Upper lip (figure 12D) symmetrically bilobed, smooth. Mandibles (figure 12A, B) with three-articulate palp; distal article of the palp with a setal formula 1-x-1x being =4; penultimate article carrying three setae; mandibular molar process strong, bordered by robust teeth; left mandible with incisor and lacinia mobilis five-toothed, followed by a row of three serrate spines; right mandible with incisor five-dentate and lacinia mobilis deeply serrate followed by a row of two serrate spines; molar flake present, rectangular and setose distally. Lower lip (figure 12E) with small inner lobes, although well demarcated; outer lobes slender, provided with short setae apically. Maxilla 1 (figure 12F ) outer lobe carrying six spine-like setae; distal article of the palp with five distal robust setae and one strong seta medially. Maxilla 2 (figure 12G) outer lobe oval, with four setae distally; inner lobe rectangular, two-thirds of outer lobe in length, carrying five setae. Maxilliped (figure 12C ) inner plate small and elongate with one tooth and three single setae; outer plate about three times as long as inner plate, with five setae; penultimate article of the palp with a distal projection; dactylus with setulae distally and with a fine seta subdistally. Antennae. Antenna 1 (figure 13A) about half of body length; peduncle densely setose; flagellum 11-articulate. Antenna 2 (figure 13B) as long as the first two articles of peduncle of antenna 1; proximal article of peduncle provided with an acute projection; the remaining articles of peduncle profusely setose; flagellum two-articulate. Gnathopods. Gnathopod 1 (figure 13C ) basis as long as ischium to carpus combined; propodus triangular with a proximal grasping spine; grasping margin of propodus palm and dactylus minutely serrate. Gnathopod 2 (figure 13D) inserted on the anterior half of pereonite 2; basis as long as pereonite 2; ischium short and rectangular; merus acute ventrally; carpus short and triangular; propodus about twice as long as basis, setose dorsally and ventrally; palm provided with a rectangular projection proximally provided with a small tooth and a distal knotch; dactylus large, curved medially, carrying short setae ventrally on the distal half. Pereopods. Pereopods 3 and 4 consisting of one article. Pereopod 3 (figure 14A) with nine single long setae apically and one short plumose seta subdistally. Pereopod

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4 (figure 14B) with seven single setae and one plumose seta. Pereopods 5–7 (figure 14C–E) similar, increasing in length, respectively; palm of propodus with a proximal row of three, four and seven short spines on pereopods 5, 6 and 7, respectively; merus to propodus setose; dactylus smooth, about half as long as propodus. Penes (figure 14F ). Penes triangular, laterally placed. Abdomen (figure 14F ). Abdomen with a pair of appendages, a pair of lateral lobes and a single dorsal lobe. Appendages serrate distally. Lateral lobes very setose. Dorsal lobe carrying a pair of short plumose setae. Female ‘b’ Body length 4.82 mm. Pereonite 1 smooth. The lateral acute projections on pereonite 2, present in male, are lacking in female (figure 11B). Flagellum of antenna 1 with seven articles (figure 11B). Propodus of gnathopod 2 (figure 13E) shorter and wider than in male, without rectangular projection proximally; dorsal surface scarcely setose; dactylus shorter than in male and not curved medially. First pair of oostegites scarcely setose; second pair smooth (figure 11B). Abdomen (figure 14G) without appendages; a pair of lateral setose lobes and a single dorsal lobe carrying two simple setae. Intraspecific variation The antennae and body projections are very constant in mature specimens. In connection with the mouthparts, the setal formula of the apical article of mandible palp is 1-4-1 or 1-5-1; the presence of six setae on the outer lobe in maxilla 1 and one tooth on the inner plate of maxilliped is very constant. The structure of the mandibles is also constant in all specimens; left mandible with five-toothed incisor, five-toothed lacinia and three spines; right mandible with five-toothed incisor, serrate lacinia, two spines and molar flake present. Ontogenetic development The acute projection on the head is already present in the juvenile stages, although other dorsal and lateral projections appear through development (figure 15). Although the grasping spine on the palm of gnathopod 2 propodus is present in the first stages, the rectangular projection becomes more evident in final phases. With development, the ratio length/width of the gnathopod 2 propodus increases, the number of dorsal and ventral setae of gnathopod 2 also increases and the proximal projection on the propodus palm becomes constricted, being more elongate near the carpus; the dactylus increases in length during development and becomes curved and setose only in the final stages. Remarks Deutella venenosa Mayer, 1890 was described by Mayer (1890) based on the specimens collected from Coquimbo, Chile, during the ‘Siboga Expedition’. A century later, the presence of Deutella venenosa in Chilean waters is confirmed. The present description is in good agreement with the sparse description and figures of Mayer (1890), except for the structure of pereopods 3 and 4 which are two-articulate in specimens described by Mayer (1890) versus one-articulate in the recently collected and herein redescribed material. The feature of gnathopod 2 and the body


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ornamentation of this species allow Deutella venenosa to be differentiated from the remaining species of Deutella. Key to the species of Deutella The following key is based on examination of type and non-type male specimens. The species key provided is meant as an easy field guide to be used without dissection. 1 Body with dorsal projections . – Body dorsally smooth . .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

2 6

2 Dorsal projections on head to pereonite 4. Pereopods 3 and 4 generally one-articulate . . . . . . . . . . . . . . . Deutella venenosa (figures 11–15) – Pereonites 3 and 4 without dorsal projections. Pereopods 3 and 4 two-articulate . . 3 3 Dorsal projections only on head . . . – Dorsal projections on head to pereonite 2

. .

. .

. .

. .

. .

.

Deutella vemae (figure 10) . . . . . . 4

4 Pereopod 5 abnormal, dactylus extremely reduced. Antennae densely setose . . . . . . . . . . . . . . . . . . . . . Deutella aspiducha (figure 1) – Pereopod 5 not reduced. Antennae not setose . . . . . . . . . . . 5 5 Propodus of gnathopod 2 widened distally, profusely setose. Pereopods 3 and 4, onesixth as long as gills . . . . . . . . . . Deutella californica (figure 2) – Propodus of gnathopod 2 not widened distally, scarcely setose. Pereopods 3 and 4, one-third as long as gills . . . . . . . . . . Deutella incerta (figure 3) 6 Propodus of gnathopod 2 with a triangular projection proximally . . . . . . . . . . . . . . . . . . . . . . . . Deutella mayeri (figure 8) – Propodus of gnathopod 2 with a rectangular projection proximally . . . . . 7 7 Body elongate. Antenna 1 scarcely setose. Pereopods 3 and 4 about half as long as gills . . . . . . . . . . . . . . . Deutella margaritae (figures 4–7) – Body not elongate. Antenna 1 setose. Pereopod 3 and 4 about one-quarter as long as gills . . . . . . . . . . . . . . . Deutella schieckei (figure 9)

Discussion The detailed comparison of morphological characters among the species of Deutella (table 1) supports the combination of the genus Luconacia and Deutella as the author accepts throughout the present paper. There is no evident pattern which would enable us to recognize species groups within the genus since the similarity among species depends on the selected character. The genus Deutella is widely distributed along the latitudinal gradient from Alaska in the Northern Hemisphere to Subantarctic waters in the Southern Hemisphere (figure 16). Nevertheless, this genus is quite restricted along the longitudinal gradient. Apart from D. schieckei, which reaches Mediterranean waters, the remaining species are limited to American coasts (Pacific or Atlantic). So far, no Deutella species has been found in the Indian Ocean. In a revision of Caprellid taxonomy, Laubitz (1993) considered 10 families in the suborder Caprellidea and she transferred the genus Deutella from the family Protellidae McCain, 1970 to the new family Pariambidae Laubitz, 1993, mainly on the basis of lacking a molar flake, a different setal formula than 1-x-y-1 and six instead of seven spiniform setae on the outer plate of maxilla 1. As Larsen (1997) pointed out, the classification of Laubitz does not agree with the relationships suggested by Takeuchi (1993) and are inconsistent, since the genera Abyssicaprella McCain, 1966 and Paradicaprella Hirayama, 1990 are not included in the new family

Table 1.

Detailed comparison among the species of Deutella based on consulting material from Museums, specimens newly collected and literature.

Pereopod 5 Male abdominal appendages

Reduced 1-articulate

D. incerta

D. margaritae

D. mayeri

D. schieckei

D. vemae

D. venenosa

5.5 3.8 Present

9 8 Present

7.8 6.2 Absent

4 3 Absent

4.5 3.5 Absent

13.5 12 Present

5.7 4.8 Present

6–7 6–7 2

6–8 6 2

Present

Absent

Absent

Absent

Absent

1-x-1, x=9 5-toothed 4-toothed Serrate Present

1 or 2 setae 5-toothed 5-toothed Serrate Absent

2 setae 5-toothed 5-toothed Serrate Absent

1-x-1, x=11 5-toothed 5-toothed Serrate Absent

1-x-1, x=4–5 5-toothed 5-toothed

12 12 2 Absent

10–11 10 2 Present

1-x-1, x=3–5 1-x-1, x=3–10 5-toothed 5-toothed 5-toothed 5-toothed Serrate Serrate Absent Absent

14 10 2

11 9 2

11 7 2

Present

6

5–6

5

4–5

5

6

6

3

4

4

3–4

4

4

5

4 5

5–7 4–5

3 4

5–6 4–5

4 4

5 5

4 5

No tooth 3 setae 5–6 setae Present

No tooth 4 setae 5–7 setae Absent

1 tooth 4 setae 4–5 setae Absent

No tooth 3–4 setae 12 setae Absent

1 tooth 3–4 setae 7 setae Present

No tooth 3 setae 4–5 setae Absent

1 tooth 3 setae 5 setae Present

1

2

2

1

1

2

1

Rectangular

Rectangular

Rectangular

Triangular

Rectangular

Rectangular

Rectangular

2-articulate

2-articulate

2-articulate

2-articulate

2-articulate

2-articulate

Normal 1-articulate

Normal 1-articulate

Normal 2-articulate

Normal 1-articulate

Normal 1-articulate

Normal 1-articulate

1 or 2-articulate Normal 1-articulate


Body length (mm) Male 4.8 Female 4.2 Dorsal projections Present Antenna 1 flagellar articles Male 6–7 Female 4 Antenna 2 flagellar articles 2 Mandibles Knobs on distal article Present of palp Setal formula 1-x-1, x=5 Left and right incisor 6-toothed Left lacinia mobilis Serrate Rigth lacinia mobilis Serrate Molar flake Absent Maxilla 1 Distal spines of outer 5 lobe Distal spines of palp 3 Maxilla 2 Setae of outer lobe 4 Setae of inner lobe 3 Maxilliped Inner plate No tooth 2 setae Outer plate 4–5 setae Distal projection on Absent penultimate article of palp Gnathopod 1 grasping 2 spines Proximal projection of the Rectangular propodus of gnathopod 2 male Pereopods 3 and 4 2-articulate

D. californica

1082

D. aspiducha


1083

F. 16. Biogeographical distribution of the Deutella species.

and also lack a molar flake. Furthermore, the present study has revealed that Deutella venenosa Mayer, 1890 and the new species Deutella margaritae possess a molar flake. This indicates that the presence/absence of a molar flake should not be considered as a good character to differentiate among families. At present, taking into account that the phylogeny of the Caprellidea is still under debate, it is probably better to maintain a smaller number of families. So, Takeuchi (1993) considered only five families and placed the genus Deutella in the family Caprellidae White, 1847 as defined by Vassilenko (1974). As Takeuchi (1993) pointed out, the following studies are needed urgently to address the phylogeny of the Caprellidea: (1) redescription of each genus and species in order to find further generic characters, (2) discovery of presently unknown genera and species from the tropics to the Southern Hemisphere and the deep sea, (3) molecular analysis based on sequencing mitochondrial DNA or ribosomal RNA and (4) ecological and behavioural studies. Acknowledgements The author is very grateful to Elizabeth Nelson (National Museum of Natural History), Elizabeth Borda (The American Museum of Natural History), Ardis B. Johnston (Museum of Comparative Zoology) and Judith C. Price (Canadian Museum of Nature) for the loan of type and non-type material of Deutella species. Special thanks to E. Nelson for her kindness and hospitality during the short stay at the National Museum of Natural History. The author also thanks Martin Thiel for hospitality and facilities provided during the stay at the Facultad de Ciencias del Mar, Universidad Cato´lica del Norte, Coquimbo Chile. The work was partially supported by a grant AP98 28617065 from the Ministry of Education, Culture and Sport from Spain.

1084


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