Eperiella hastings Rix & Harvey, 2010

Rix, Michael & Harvey, Mark, 2010, The spider family Micropholcommatidae (Arachnida: Araneae: Araneoidea): a relimitation and revision at the generic level, ZooKeys 36 (36), pp. 1-321 : 69-70

Eperiella hastings Rix & Harvey , sp. n.

urn:lsid:zoobank.org:act:AB7104B0-40F3-4EE5-BB1D-012296F3CB55

Figs 112C–D, 113–114, 213

Type material. Holotype male: Bug Hole (H-X3), Hastings karst, Tasmania, Australia, from cave wall, 43°23'S, 146°51'E, 21.iv.1988, S. Eberhard ( QVM 13 : 13533).

Paratypes: Allotype female, same data as holotype ( QVM 13 : 44521); 2 females, same data as holotype ( QVM 13 : 44522) .

Etymology. The specific epithet is a noun in apposition, taken from the type locality.

Diagnosis. Males and females of Eperiella hastings can be distinguished from E. alsophila by the presence of only six vestigial eye spots (Fig. 113C). Both sexes can also be recognised by the Tasmanian cave distribution (Fig. 213).

Description. Holotype male: Total length 0.77. Carapace 0.41 long, 0.34 wide. Abdomen 0.44 long, 0.28 wide. Leg I femur 0.29. Body colour pale cream. Carapace raised anteriorly, not fused to sternum except around petiole; dorsal surface of pars ce- phalica slightly convex in lateral view. Eyes reduced to six vestigial eye spots on anterior margin of pars cephalica. Chelicerae each with bulging anterior projection; promargin with two peg teeth. Legs relatively short (leg I femur-carapace ratio 0.71); macrosetae absent. Abdomen oval, covered with hair-like setae; dorsal scute and lateral sclerotic strips absent. Pedipalpal patella with retrolaterally-directed, hooked lRPA and ornate, ridged cuticular microstructure; tegulum smooth, with curved, marginal ETR; embolus very long (length >> 5× width), coiling 3× around margin of tegulum (Fig. 114).

Allotype female: Total length 0.94. Carapace 0.45 long, 0.32 wide. Abdomen 0.57 long, 0.36 wide. Leg I femur 0.27. Cephalothorax, legs pale tan-yellow; abdomen pale cream. Carapace raised anteriorly, not fused to sternum except around petiole; dorsal surface of pars cephalica slightly convex in lateral view. Eyes reduced to six vestigial eye spots on anterior margin of carapace. Chelicerae without bulging anterior projections; promargin without peg teeth. Legs relatively short (leg I femur-carapace ratio 0.60); macrosetae absent. Abdomen oval, covered with hair-like setae; dorsal scute and lateral sclerotic strips absent. Pedipalp entire, five-segmented. Epigyne with distinctive, ‘drumstick-shaped’ external morphology (Fig. 113D); receptacula with globular posterior spermathecae; insemination ducts coiled around receptacula; fertilisation ducts ventrally-looped (Figs 112C–D).

Distribution. Known only from the cave Bug Hole in the Hastings karst of southern Tasmania (Fig. 213).

Remarks. Eperiella hastings is an extremely rare and enigmatic spider from the Hastings karst of southern Tasmania (Fig. 213). The species has no known close relatives in Australasia, and seems clearly congeneric only with E. alsophila from southern Chile. The Hastings Caves are home to a significant diversity of troglobitic arthropods ( Eberhard et al. 1991), and the presence here of this extraordinary species is of the greatest biogeographic interest and conservation concern.