New taxa of Rhagidiidae (Acari: Prostigmata) from North America. Part ...

Can. J. Zool. Downloaded from www.nrcresearchpress.com by China University of Science and Technology on 06/06/13 For personal use only.

New taxa of Rhagidiidae (Acari: Prostigmata) from North America. Part IV. Genus Foveacheles Zacharda, with a key to world species Miloslav Zacharda

Abstract: Two new species of rhagidiid mites from the Nearctic region, Foveacheles pribilovi n.sp. and F. mexicana n.sp., are described. A detailed description of F. arenaria (Willmann) based on Canadian material is given. A key to adults of the known subgenera and 31 species of the genus Foveacheles Zacharda for the world is presented. RCsumC : On trouvera ici la description de deux nouvelles espkces nkarctiques d'acariens rhagidiidks, Foveacheles pnvilovi n.sp. et F. mexicana n.sp., de mCme qu'une description dCtaillCe de F. arenaria (Willmann) basCe sur l'examen de spkcimens canadiens. Une clC d'identification, a 1'Cchelle mondiale, des adultes des sous-genres actuels et de 31 espkces du genre Foveacheles Zacharda est Cgalement prCsentCe. [Traduit par la Redaction]

Introduction Predatory soil mites of the family Rhagidiidae are morphologically a uniform group whose representatives frequently differ only in subtle structural characters. Primarily for this reason, only two genera, i.e., Rhagidia Thorell (1 872) with filiform trichobothria sc, and Coccorhagidia Thor (1934) with clavate trichobothria, were distinguished in this family until recently (for example, see Thor and Willmann 194.1 or Strandtmann 1971). Subsequently, in a monograph (Zacharda 1980) based on a revision of diverse material of previously described and newly described taxa, I proposed the genus Foveacheles for species of rhagidiid mites with the following characteristics: filiform trichobothria; typical chelicerae with a distinct dorsal saddle-shaped depression; fixed cheliceral digit with a soft, sharp dorsal ridge (seen in lateral aspect) under which the distal cheliceral seta is inserted dorsolaterally, usually in a proximally open depression, whilst the proximal seta is inserted dorsally; rhagidial organs on leg tarsi I and I1 each with 3-5 rhagidial solenidia and 1 stellate, or spiniform, famulus ( E ) ; epimeral formula 3- 1-5-3, 3- 1-6-6, or, exceptionally, 3-1-6-4; claws on the leg tarsi with distinct ventrobasal clawlets. Since then five species of the genus Foveacheles from the Nearctic region have been described: F. bentonensis Zacharda (1983a), ~ ~ ~ a r a l l e l o sZacharda eta (1985), F. vancouverensis Zacharda (1986), F. auricularia Zacharda and Elliott, and F. titanica Zacharda and Elliott (1985). Representatives of the genus ~ ~ seem to have ~ a worldwide ~ distri-~ bution, as some of them have been reported also from the Palearctic (Zacharda 1983b, 1988, 1994a), Hawaiian Received May 5, 1995. Accepted September 29, 1995.

M. Zacharda. Institute of Landscape Ecology2 Czech Academy of Sciences, Na sAdk6ch 7, 37005 CeskC Budiijovice, Czech Republic. Can. J. Zool. 74: 343-356 (1996). Printed in Canada / ImprimC au Canada

(Zacharda 1982), and Oriental (Zacharda 1994b) regions. However, it must be stressed that the representatives of the genus Foveacheles discovered so far in North America should be considered to represent only a fragment of the species diversity of the genus that actually exists in the Nearctic region. The 31 species in the genus known so far are very similar morphologically. The need for reliable classification within this group of similar species has led to their being grouped into 10 subgenera (Zacharda 1980, 1982, 1988, 1994b). Morphological distinctions between these groupings are given in the key below. Here I present descriptions of two new species, F. pribilovi n.sp. and F. mexicana n.sp., from among the Nearctic material in the Canadian National Collection of Insects and Arachnids (CNC) housed in the Biological Resources Division, Agriculture and Agri-Food Canada, Ottawa. A detailed description of F. arenaria (Willmann) based on Canadian material is also given because this species was initially redescribed from fragmentary and distorted type specimens and only a few drawings of important morphological characters were presented (Zacharda 1980). The type material of the new taxa is deposited in ,the CNC as mounts in Hoyer's medium on microscope slides.

Materia[ and methods Mites previously mounted on microscope slides were removed, transferred to lactic slide ~ h acid in temporary ~ l preparations ~ (Krantz ~ 1978).and examined under a standard light microscope using bright field without phase contrast. These specimens were then remounted in Hoyer, medium on microscope slides. ~ e ; m i n o l o and ~ ~ setal notation follow those proposed by Lindquist and Zacharda (1987) and Baker (1990), who applied new descriptive formats and morphological terminologies to the Rhagidiidae, largely based on the general schemes for acariform mites (e. g., Grandjean 1934, 1939). Measurement criteria follow those of Zacharda (1980).

Can. J. Zool. Vol. 74, 1996

Genus Foveacheles Zacharda Foveacheles Zacharda, 1980, pp. 66 1 - 662. Subgenus Mediostella Zacharda Mediostella Zacharda, 1980, p. 672.


Foveacheles (Mediostella) pribilovi n. sp . Figs. 1-3

Diagnosis Rhagidial organ I with 4 separate oblique solenidia and 1 stellate famulus positioned between 2nd and 3rd solenidia antaxially. Rhagidial organ I1 with 4 separate solenidia arranged in tandem axially and 1 spiniform famulus subtending proximal solenidion. Spiniform solenidion on tibia IV inserted lateroventrally . Description Adult female (1 examined). Length of idiosoma 960 pm (Fig. I), width of idiosoma at level of humeral setae c2 432 pm. Ratio of leg I length to idiosomal length 1.1. Gnathosomu Subcapitulum moderately slender, oval (Fig. 21); ratio of length to breadth 1.1; distal hypostomal lips with spiniform internal and serrate external malar processes; adoral setae nude; proximal subcapitular setae ciliate, external pair slightly longer than internal pair. Chelicerae robust, dorsal surface with saddle-shaped depression slightly distal to level of bases of digits (Figs. 2A-2C); cheliceral digits short, robust; fixed digit terminates in 2 cusps, smooth along masticatory surface; movable digit serrated along approximately distal half of masticatory surface. Chelicerae with 2 setae, proximal one inserted just distad of articulation of movable digit; tip of proximal seta nearly reaches insertion of distal seta; tip of distal seta overlaps apex of fixed digit. Length of chelicera 234 pm, dorsoventral width 99 pm, length of movable digit 86 pm, length of proximal and distal cheliceral setae 26 and 39 pm, respectively, distance between their insertions 30 pm. Ratio of cheliceral length to dorsoventral width 2.4; ratio of length of movable digit to length of chelicera 0.4; ratio of length of movable digit to dorsoventral width of chelicera 0.9. Palpus strong and slender with relatively slender tarsus with small terminal tubercle (Figs. 2G, 2H); ratio of length to width of tarsus 2.36. Length of palpal trochanter , femorogenu , tibia and tarsus 33, 102, 43, and 92 pm, respectively. Number of setae and solenidia (in parentheses) on palpal trochanter, femorogenu, tibia and tarsus 0-2-3-10(1), respectively; tarsal solenidion spiniform, erect. Prodorsum Naso well-developed, with a pair of internal vertical setae vl (Fig. 1A). Bothridial setae scl filiform, finely pubescent. Length of setae: vl 56 pm, v2 46 pm, scl 96 pm, sc2 119 pm; transverse intervals between paired setae vl - vl 13 pm, v2 -v2 125 pm, scl -scl 56 pm, sc2-sc2 198 pm. Opisthosomul dorsum Complement and arrangement of dorsal setae and cupules typical of Rhagidiidae (Fig. 1A); four pairs of cupules;

ia positioned laterally between setae cl and d l , im lateral to setae e l , ip slightly lateral and just anterior to f2. Cupules ih positioned ventrolaterally, postero-laterad of posteriormost pair of aggenital setae (Fig. 1B). Setae cl and d l reach about 0.6 of distance to insertion of successive seta; seta e l reaches about 0.4 of distance to insertion of f l ; seta fl reaches nearly to insertion of h l . Length of setae: cl 63 pm, c2 132 pm, d l 59 pm, el 59 pm, f l 99 pm, f2 66 pm, hl 115 pm, h2 59 pm. Podosomu Coxisternal plates (epimeres) I,II,III,IV with 3-1-6-3 finely pubescent setae, respectively (Fig. 1B). Genital region Genital valves each with 5 finely pubescent setae of similar length, about 30 - 37 pm, arranged evenly along medial edge of valve (Fig. 1B). Five pairs of aggenital (paragenital) setae of similar length, about 50 pm. Length of genital valves 132 pm. Legs Leg I 1056 pm long, about 1.1 as long as idiosoma. Empodia all setulose, broadly oval in dorsoventral view, slightly longer than claws; claws each with small clawlet ventrobasally. Number of setae and solenidia (solenidia and famulus (E) in parentheses), respectively, on legs I-11-111-IV: trochanters 1- 1-2-2; basifemora telofemora 5 5-6 54 +4-3 +4; genua 1l(1)-9(1)-7(1)-6; tibiae 13(2)-7(2)-7(2)7(1); tarsi 21(4+~)-16(4+E)-14-14 (Fig. 3). Genua I and I1 each with 1 erect spiniform solenidion ventrodistally, genu I11 with 1 ventromedial spiniform solenidion. Tibia I with 1 erect laterodorsal proximal spiniform solenidion and 1 dorsodistal rhagidial solenidion lying in normal shallow surface pit; tibia I1 with 1 laterodorsal proximal spiniform erect solenidion and 1 lanceolate dorsodistal solenidion recessed in deep pit with small surface pore; tibia I11 with 2 erect spiniform laterodorsal proximal solenidia arranged in tandem; tibia IV with 1 erect spiniform lateroventral medioproximal solenidion. Tarsus I slender, its tip slightly truncated in lateral view (Fig. 2F), ratio of length to width 4.46, with 4 rhagidial solenidia lying obliquely in separate pits, stellate famulus (E) inserted between 2nd and 3rd proximal rhagidial solenidia antaxially (Fig. 2D); tarsus I1 with 4 rhagidial solenidia lying in tandem in separated oblique depressions and small spiniform famulus (E) lying beside proximal rhagidial solenidion antaxially (Fig. 2E).

+

+ +

Affinities The adult of F. pribilovi n.sp. is morphologically similar to that of F. canestrini (Berlese and Trouessart) (Zacharda 1980) in having rhagidial organ I1 with 4 separate solenidia. However, with the latter species the solenidia are positioned obliquely and the spiniform famulus is positioned between the 1st and 2nd solenidia antaxially, whilst with F. pribilovi n.sp. the solenidia and the spiniform famulus in the rhagidial organ I1 are arranged in tandem axially. The length of the idiosoma with F. pribilovi n.sp. is about 960 pm, whilst with F. canestrini it is 1300 - 1420 pm.

Zacharda

34 5


Fig. 1. Foveacheles pribilovi n.sp., adult female. (A) Body dorsum. (B) Body venter. Setal notation is based on Grandjean ( 1934. 1939).

The adult of F. pribilovi n.sp. is also morphologically similar to that of F. rupestris Zacharda (1980). However, the latter species has the rhagidial organ I1 with 4 solenidia and 1 spiniform famulus arranged in tandem axially in a confluent depression. Distinctions are also given in the key below.

Material examined Holotype: Adult female, Alaska, Pribilof Islands, St. Paul's Island, "edge of pond between strand and int. hills,'' September 1976 (collector not indicated). Type material deposited in the Canadian National Collection of Insects and Arachnids, Ottawa, Type No. 22,107.

346



Fig. 2 . Foveacheles pribilovi n.sp., adult female. (A) Chelicera in lateral aspect. (B and C) Fixed digit of chelicera in detail, lateral aspect. (D) Rhagidial organ I in dorsal aspect. (E) Rhagidial organ I1 in dorsal aspect. (F) Tarsus I in lateral aspect. (G) Palpus in ventrolateral aspect. (H) Apex of palpal tarsus in lateral aspect. (I) Subcapitulum in ventral aspect.

Zacharda


Fig. 3. Foveacheles pribilovi n.sp., adult female, setal arrangement on legs in dorsal aspect. (A) Leg I. (B) Leg 11. (C) Leg 111. (D) Leg IV.

347

348



Fig. 4 . Foveacheles mexicana n.sp., adult female. (A) Chelicera in lateral aspect. (B) Cheliceral digits in detail, lateral aspect. (C) Palpus in lateral aspect. (D) Tarsus I in lateral aspect. (E) Rhagidial organ I in dorsal aspect. (F) Rhagidial organ I1 in dorsal aspect.

Zacharda


Fig. 5 . Foveacheles mexicana n.sp., adult female, setal arrangement on legs in dorsal aspect. (A) Leg I. (B) Leg 11. (C) Leg 111. (D) Leg IV.

349



Etymology The species has been named pribilovi after Gavril Pribilov, a Russian sea captain, who, as the first explorer, visited the region of collection of this rhagidiid mite, the Pribilof Islands, in 1786 and discovered their fur seal rookeries. Subgenus Usitorhagidia Zacharda Usitorhagidia Zacharda, 1980, p. 682. Foveacheles (Usitorhagidia) mexicana n .sp . Figs. 4 and 5

Diagnosis Rhagidial organ I with 4 separate and oblique solenidia and 1 stellate famulus positioned between 1st and 2nd proximal solenidia antaxially. Rhagidial organ I1 with 4 separate solenidia arranged in tandem axially and 1 spiniform famulus subtending proximal solenidion. Proximal cheliceral seta positioned distad of articulation of movable digit. Spiniform solenidion on tibia IV inserted lateroventrally. Description Adult female (2 examined). Length of idiosoma 1360 pm, width of idiosoma (interval between setae c2 and c 2 ) 384 pm. Ratio of leg I length to idiosomal length 0.8 (in damaged specimens in microscope preparations). Gnathosoma Subcapitulum moderately slender, oval, ratio of length to breadth 1.O; distal hypostomal lips with spiniform internal and serrate external malar processes; adoral setae nude; proximal subcapitular setae ciliate, external pair slightly longer than internal pair. Chelicerae moderately slender, dorsal surface with saddle-shaped depression just slightly distal to level of bases of digits (Figs. 4A, 4B); cheliceral digits short, robust; fixed digit terminates in 2 cusps, smooth along masticatory surface; movable digit serrated along approximately distal half of masticatory surface. Chelicerae with 2 setae, proximal one inserted distad of articulation of movable digit; tip of proximal seta reaches about 0.8 of distance to insertion of distal seta; tip of distal seta overlaps apex of fixed digit. Length of chelicera 280 pm, dorsoventral width 132 pm, length of movable digit 99 pm, length of proximal and distal cheliceral setae 23 and 43 pm, respectively, distance between their insertions 30 pm. Ratio of cheliceral length to dorsoventral width 2.1; ratio of length of movable digit to length of chelicera 0.3; ratio of length of movable digit to dorsoventral width of chelicera 0.7. Palpus strong and slender with relatively slender tarsus (Fig. 4C); ratio of length to width of tarsus 2.5. Length of palpal trochanter, femorogenu, tibia, and tarsus 26, 115, 39, and 109 pm, respectively. Number of setae and solenidia (in parentheses) on palpal trochanter, femorogenu, tibia, and tarsus 0-2-3-10(1), respectively; tarsal solenidion spiniform, erect. Prodorsum Naso well-developed, with a pair of internal vertical setae v , . Bothridial setae scl filiform, finely pubescent. Length of setae: v l 79 pm, v2 79 pm, scl 122 pm, sc2 148 pm; transverse intervals between paired setae vl - v1 13 pm, v2- vz 132 pm, scl -scl 56 pm, sc2-sc2 204 pm.

Opisthosomal dorsum Complement and arrangement of dorsal setae and cupules typical of Rhagidiidae; four pairs of cupules; ia positioned laterally between setae c l and d l , im lateral and just anterior to setae e l , ip (slightly lateral) between setae e l and f2. Cupules ih positioned ventrolaterally, almost laterad of posteriormost pair of aggenital setae. Length of setae: c l 63 pm, c2 torn off, d l 63 pm, e l 66 pm, f, torn off, f2 69 pm, hl 115 pm, h2 73 pm. Podosoma Coxisternal plates (epimeres) I,II,III,IV with 3- 1-6-3 finely pubescent setae, respectively.

Genital region Genital valves each with 5 finely pubescent setae of similar length, about 37 pm, arranged evenly along medial edge of valve. Five pairs of aggenital (paragenital) setae of similar length, about 50 pm. Length of genital valves 132 pm. Legs Leg I 1040 pm long, about 0.8 as long as idiosoma. Empodia all setulose, broadly oval in dorsoventral view, not overlapping claws, claws with small clawlets ventrobasally. Number of setae and solenidia (solenidia and famulus (E), in parentheses), respectively, on legs I-11-111-IV: trochanters 1- 1-2-2; basifemora + telofemora 5 +5-6 +5-4 +4-3 +4; genua 1l(1)9(1)-7(1)-6; tibiae ll(2)-7(2)-7(2)-7(1); tarsi 1 9 ( 4 + ~ ) 16(4+~)-14-14(Fig. 5). Genua I and I1 each with 1 short, erect spiniform solenidion ventrodistally, genu I11 with 1 ventral distomedial small spiniform solenidion. Tibia I with 1 dorsoproximal, very short and blunt erect spiniform solenidion and 1 dorsodistal rhagidial solenidion recessed in deep insertion; tibia I1 with 1 laterodorsal proximal spiniform erect solenidion and 1 lanceolate dorsodistal solenidion recessed in deep pit with small surface pore; tibia I11 with 2 erect spiniform laterodorsal, proximal solenidia arranged in tandem; tibia IV with 1 small erect spiniform lateroventral medial solenidion. Tarsus I slender, its tip suddenly truncated in lateral view (Fig. 4D), ratio of length to width 3.70, with 4 rhagidial solenidia lying obliquely in separate pits, stellate famulus (E) inserted between 1st and 2nd proximal rhagidial solenidia antaxially (Fig. 4E); tarsus I1 with 4 rhagidial solenidia lying in tandem in separate depressions and small spiniform famulus (E) posterolateral to proximal rhagidial solenidion (Fig. 4F).

Affinities In the group of species of the subgenus Usitorhagidia, adults of F. mexicana n.sp. are morphologically similar to those of F. bentonensis Zacharda (1983~)in having the rhagidial organ I1 with 4 solenidia and 1 spiniform famulus. However, with F. mexicana n.sp., the solenidia in the rhagidial organ I1 are positioned in separate depressions, whilst with F. bentonensis the solenidia and spiniform famulus in the rhagidial organ I1 lie in a confluent depression. With F. mexicana n.sp., the proximal cheliceral seta is positioned distad of the articulation of the movable digit, whilst with F. bentonensis the proximal cheliceral seta is positioned

Zacharda


Fig. 6 . Foveacheles arenaria (Willmann), adult female. (A) Chelicera in lateral aspect. (B) Subcapitulum in ventral aspect. (C) Rhagidial organ I in dorsal aspect. (D) Rhagidial organ I1 in dorsal aspect. (E) Palpus in lateral aspect. (F) Tarsus I in lateral aspect. (G) Dorsodistal rhagidial solenidion on tibia I.

opposite the articulation of the movable digit. Distinctions are also given in the key below.

Material examined Holotype: Adult female, Mexico, 15 mi (1 mi = 1.609 krn) SW El Salto, Durango, spruce duff, 3 July 1964, coll. E.E. Lindquist; paratype: adult female, Mexico, 10 mi W El Salto, Durango, mixed pine and madrone duff, 1 July

1964, coll. E.E. Lindquist. Type material deposited in the Canadian National Collection of Insects and Arachnids, Ottawa, Type No. 22,108.

Etymology The specific name mexicana refers to the region where the species was discovered.

352



Fig. 7 . Foveacheles arenaria (Willmann), adult female, setal arrangement on legs in dorsal aspect. (A) Leg I. (B) Leg 11. (C) Leg 111. (D) Leg IV.

Foveacheles (Usitorhagidia) arenaria (W illmann, 1952) Figs. 6 and 7 Rhagidia arenaria Willmann, 1952, pp. 155 - 156. Rhagidia arenaria sensu Ehrnsberger 1977, pp. 67 - 73. F. (U.) arenaria sensu Zacharda 1980, pp. 682 -684.

Description of the Canadian material Adult female (3 examined). Length of idiosoma 784.-

848 pm, width of idiosoma at level of humeral setae c2 256-320 pm. Ratio of leg I length to idiosomal length 0.85 -0.87. Gnathosoma Subcapitulum oval, short (Fig. 6B); ratio of length to breadth 1.O; distal hypostomal lips with spiniform internal and soft smooth external malar processes; adoral setae nude; proximal subcapitular setae ciliate, external pair slightly longer


Zac ha rda

than internal pair. Chelicerae moderately slender, robust, dorsal surface with saddle-shaped depression slightly distal to level of bases of digits (Fig. 6A); cheliceral digits long, robust; fixed digit terminates in 3 blunt cusps, smooth along masticatory surface; movable digit serrated along approximately distal third of masticatory surface. Chelicerae with 2 setae, the proximal one inserted opposite to articulation of movable digit; tip of proximal seta reaches 0.5 -0.7 of distance to insertion of distal seta, which is inserted distinctly distad of half length of fixed digit; tip of distal seta overlaps apex of fixed digit. Length of chelicera 172 - 181 pm, dorsoventral width 59-72 pm, length of movable digit 6269 pm, length of proximal and distal cheliceral setae 16-23 and 16-24 pm, respectively, distance between their insertions 33 pm. Ratio of cheliceral length to dorsoventral width 2.5-2.9; ratio of length of movable digit to length of chelicera 0.4; ratio of length of movable digit to dorsoventral width of chelicera 0.9 - 1.O. Palpus strong and short with relatively robust tarsus (Fig. 6E); ratio of length to width of tarsus 2.1 -2.4. Length of palpal trochanter, femorogenu, tibia, and tarsus 23-33, 66-72, 29-30, and 62-72 pm, respectively. Number of setae and solenidia (in parentheses) on palpal trochanter, femorogenu, tibia, and tarsus 0-2-3- 10(1), respectively; tarsal solenidion spiniform, erect. Prodorsum Naso well-developed, with a pair of internal vertical setae vl. Bothridial setae scl filiform, finely pubescent. Length of setae: v2 23-29 pm, v2 36-46 pm, scl 62-72 pm, sc2 82 - 86 pm; transverse intervals between paired setae vl - vl 10 pm, v2-v2 86-93 pm, scl -scl 39-43 pm, sc2-sc2 138- 148 pm. Opisthosomal dorsum Complement and arrangement of dorsal setae and cupules typical of Rhagidiidae; four pairs of cupules; ia positioned laterally between setae cl and d l , im lateral and just anterior to setae e l , ip between setae el and f2. Cupules ih positioned ventrolaterally, almost laterad of posteriormost pair of aggenital setae. Setae cl, d l , el, and f l reach about 0.3, 0.4, 0.3, and 0.7 of distance to insertion of successive seta. Length of setae: cl 39-46 pm, c2 76-86 pm, dl 3643 pm, el 36-43 pm, f, 65 pm, f2 39-46 pm, hl 7278 pm, h2 49-53 pm.

353

Podosoma Coxisternal plates (epimeres) I ,II,III,IV with 3- 1-6-3 finely pubescent setae, respectively. Genital region Genital valves each with 5 finely pubescent setae of similar length, about 25 pm, arranged evenly along medial edge of valve. Five pairs of aggenital (paragenital) setae of similar length, about 37 pm. Length of genital valves 112 - 119 pm. Legs Leg I 672-736 pm long, about 0.8-0.9 as long as idiosoma. Empodia all setulose, broadly oval in dorsoventral view, slightly longer than claws; claws each with small clawlet ventrobasally. Number of setae and solenidia (solenidia and famulus (E), in parentheses), respectively, on legs I-11-111-IV: trochanters 1- 1-2-2; basifemora telofemora 5 5-6+5-4 +4-3 +4; genua 1l(1)-9(1)-7(1)-6; tibiae +E)-14-14 (Fig. 7). 1l(2)-8(2)-7(1)-7(1); tarsi 19(4+~)-16(3 Genua I and I1 each with 1 erect spiniform solenidion ventromediodistally, just behind, or between, 1st ventrodistal pair of setae, genu I11 with 1 small spiniform ventromedial solenidion. Tibia I with 1 erect laterodorsal , medioproximal spiniform solenidion and 1 dorsodistal rhagidial solenidion (Fig. 6G); tibia I1 with 1 erect dorsolateral, medial to medioproximal spiniform solenidion and 1 lanceolate dorsodistal solenidion recessed in deep pit with small surface pore; tibia 111 with 1 small erect spiniform laterodorsal, medial solenidion; tibia IV with 1 very small, erect spiniform dorsolateral proximal solenidion. Tarsus I slender, its tip sligh,tly truncated in lateral view (Fig. 6F), ratio of length to width 3.3 3.9, with 4 rhagidial solenidia lying obliquely in separate pits, stellate famulus (E) inserted between 1st and 2nd proximal rhagidial solenidia antaxially (Fig. 6C); tarsus I1 with 3 rhagidial solenidia lying in separate oblique depressions and small spiniform famulus (E) subtending axially proximal rhagidial solenidion (Fig. 6D).

+

+

Material examined Three adult females, Canada, New Brunswick, Kent Co., Kouchibouguac National Park, Kelly's Beach, under rocks, coll. I.M. Smith; deposited in the Canadian National Collection of Insects and Arachnids, Ottawa, as microscope preparations in the collection of Rhagidiidae.

Key to adults of subgenera and species of the genus Foveacheles Zacharda l a . Dorsal opisthosomal setae f2 absent; trochanter IV with 3 ciliated setae. Known only from South Vietnam (subgenus Achaetorhagidia Zacharda(1994b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 16. Dorsal opisthosomal setae f2 present; trochanter IV with 2 ciliated setae. Known from Holarctic and Hawaiian regions . . . 2a. Setae on idiosoma and appendages darker in colour than integument; dorsodistal rhagidial solenidion on tibia I short, not reaching intersegmental articulation between tibia and tarsus; length of idiosoma about 530-670 pm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F. (A.)tropica Zacharda(l994b) 26. Setae on idiosoma and appendages whitish, i.e., same colour as integument; dorsodistal rhagidial solenidion on tibia I long, reaching intersegmental articulation between tibia and tarsus; length of idiosoma about 490-560 pm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F. (A*) namcatiensis Zacharda (1994b) 3a. Rhagidial organs I and I1 each with 5 solenidia and with 1 stellate and 1 spiniform famulus, respectively (subgenus Propriorhagidia Zacharda(1980)) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 36. Rhagidial organ I with 3-5 solenidia and stellate famulus, rhagidial organ I1 with 3 or 4 solenidia and spiniform famulus