Hemicloeina Simon

PLATNICK, NORMAN I., 2002, A Revision Of The Australasian Ground Spiders Of The Families Ammoxenidae, Cithaeronidae, Gallieniellidae, And Trochanteriidae (Araneae: Gnaphosoidea), Bulletin of the American Museum of Natural History 2002 (271), pp. 1-1 : 1-

Hemicloeina Simon

Hemicloeina Simon, 1893: 346 (type species by original designation Hemicloea somersetensis Thorell ).

NOTE: The application of this generic name could be disputed. The type species, Hemicloea somersetensis , was originally described by Thorell (1881) on the basis of juveniles collected at Somerset, at the northern tip of Cape York, by L. M. D’Albertis. Simon’s concept of the type species was seemingly based on one juvenile (MNHN 6725) from this collection, apparently donated to Simon by Thorell in 1884. Simon separated the genus from what he considered its closest relative, Rebilus , by the simple, conical posterior median spinnerets. Those relatively unmodified spinnerets, however, are characteristic only of juveniles, which have not yet developed the massive array of cylindrical gland spigots found on the posterior median spinnerets of adult females. On this basis, Hemicloeina could be regarded as simply an ill­founded synonym of Rebilus . However, only one trochanteriid species is currently known from Somerset and adjacent areas near the tip of Cape York, and it belongs to a group that is clearly distinguishable from Rebilus . It seems best, therefore, to use Thorell’s specific name for that species, and Simon’s generic name for the group to which it belongs.

DIAGNOSIS: This appears to be the sister group of Rebilus , sharing with it a common male palpal conformation and the presence of a few tiny denticles on the proclaw of leg I. The two genera seem to be largely allopatric, although there may be some limited areas of sympatry in Queensland. Males of Hemicloeina can easily be distinguished from those of Rebilus by the deeply incised, almost chelate tip of the palpal conductor (figs. 541, 545); females of Hemicloeina have a rather different epigynal conformation, with much more coalesced spermathecae (figs. 544, 548) and without the laterally and anteriorly convoluted epigynal ducts typical of Rebilus .

DESCRIPTION: Large spiders, total length of males 7–12, of females 9–18. Carapace flattened, without tubercles, with rebordered lateral and posterior margins, evenly coated with scattered, dark, stiff, short, erect setae interspersed among white, recumbent setae; longer, erect, dark setae present only in ocular area and on clypeus; thoracic groove long, Y­shaped, wider anteriorly than posteriorly; cephalic groove pronounced, additional intercoxal grooves still discernible. Eight eyes in two rows, posterior medians smaller than other, subequal eyes; anterior medians circular, light, posterior medians circular, lenses slightly flattened, canoeshaped tapetum apparently lost, laterals oval; from above, both eye rows slightly recurved, from front, both rows slightly procurved; anterior medians separated by more than their diameter, farther from anterior laterals; posterior medians separated by about three times their diameter, slightly closer to posterior laterals; anterior and posterior laterals separated by more than their diameters; median ocular quadrangle much wider in back than in front or than long. Chelicerae porrect, divergent, with distinct oblique groove just below clypeus; anterior surface coated with stiff setae; chilum very wide, triangular, unipartite, entire, accompanied by second, elongated, posterior chilum (narrow, I­shaped sclerite separating bases of chelicerae posteriorly); chelicerae with distinct lateral boss, promargin with series of long setae originating in line along base of fang, those nearest base of fang bent; promargin with three teeth, proximal tooth smaller than others, distalmost tooth separated from other two, retromargin with two widely separated teeth; presumptive cheliceral gland openings near base of proximal tooth. Labium rectangular, flat, posterior one­quarter narrowed, anterior margin truncate. Endites long, divergent, with oblique depression restricted to their median edge; serrula apparently absent, sieve plate not conspicuous under light microscopy; anteromedian edges and apex bearing wide patch of long, stiff, dark setae. Sternum flat, with rebordered, slightly depressed lateral margins, not expanded anteriorly, with slight extensions to coxae, extensions between coxae represented by four pairs of small triangular sclerites separated from sternal margin by unsclerotized cuticle; surface smooth, with few long setae, posterior margin not rebordered, separating coxae IV. One weakly sclerotized epimeric sclerite on each side, not extending between coxae, not fused to carapace. Pedicel composed of two dorsal sclerites (anterior sclerite without deep posterior invagination, posterior sclerite without beak­shaped anterior extension) and weak, inverted v­shaped ventral sclerite with anteriorly unexpanded head not reaching posterior tip of sternum.

Abdomen without dorsal or anterior scutum; cuticle with weak, recumbent setae; epigastric scutum weakly sclerotized, with well­marked booklung openings at sides but without postepigastric sclerites, booklung covers not ridged; colulus represented only by scattered setae situated near narrow posterior spiracle; males apparently with scattered short epiandrous spigots. Anterior lateral spinnerets short, conical, separated by about their diameter at base, with two articles, distal article with two major ampullate gland spigots and several small, unmodified piriform gland spigots; posterior median spinnerets with several aciniform gland spigots and apparently only one larger minor ampullate gland spigot, those of males triangular, those of females bipartite, enlarged posterior portion with two parallel rows, each row with about 10 large cylindrical gland spigots; posterior lateral spinnerets with two articles, apparently without minor ampullate gland spigots, those of males seemingly with aciniform gland spigots only, those of females with two large cylindrical gland spigots in addition.

Legs laterigrade, subequal in length, most surfaces with long setae; coxae and trochanters without dorsal tubercles but coxae IV with one dorsal spiniform seta, fourth trochanters slightly elongated; anterior coxae without protuberant posterolateral corners; trochanters very slightly notched, producing sharp point at ventralmost edge; anterior metatarsi and tarsi with undivided scopula composed of short, straight setae; posterior metatarsi without distal preening brushes; tarsi with two long, smooth claws bearing no ventral teeth, except proclaw of leg I with few tiny denticles; strong claw tufts composed of two large pads of narrow setae; tarsi without cuticular cracks, relatively short; morphologically dorsal surface with modified proximal margin consisting of patch of unsclerotized cuticle followed by strong cuticular ridge, that ridge opposing distinct distal extensions situated at distal edge of metatarsi; trichobothria present, in three rows on tarsi, two on metatarsi and tibiae. Female palpal femur with strong dorsal spines, distal segments with weaker but longer spines; female palpal tarsus with long claw bearing several tiny ventral teeth, without ventral scopula. Typical leg spination pattern (counts refer to morphological surfaces, only surfaces bearing spines listed): femora: I–III d1­1­0, p1­1­0, r0­1­ 0; IV d1­0­1, p1­0­0; tibiae: I, II v1p­1p­2; III v2­2­2; IV p1­0­0, v2­2­2, r1­0­1; metatarsi: I, II v2­0­0; III v2­1p­2; IV v2­2­2, r1­0­0.

Male palpal tibia with distinct basal and distal apophyses, cymbium with thick distal scopula; cymbial surface invaginated at base; distal tip of conductor deeply incised, with chelate appearance. Epigynum with relatively chunky, coalesced spermathecae, without elaborate anterior and lateral ducts.