Olgania cracroft 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 : 92-93

Olgania cracroft Rix & Harvey , sp. n.

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Figs 178D, 179C, 180–181, 213

Type material. Holotype male: Wargata Mina (Judds Cavern) (C-1), Cracroft karst, Tasmania, Australia, from groups of sheet-webs on wall of C-17 side passage (dark zone), 43°15'S, 146°35'E, 25.XI.1989, J. Jackson ( AMS KS29532 ).

Paratypes: Allotype female, same data as holotype ( AMS KS97161 ); 1 female, same data as holotype ( AMS KS97162 ); 4 females, same data as holotype ( QVM 13 : 12662) .

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

Diagnosis. Males of Olgania cracroft can be distinguished from all other described congeners except O. troglodytes by the absence of prolateral, thorn-like macrosetae on the male pedipalpal tibia; and from O. troglodytes by the coiled embolus (Fig. 181). Females can be distinguished from all other described congeners by the distinctive, inverted L-shaped receptacula with coiled insemination ducts (Fig. 178D).

Description. Holotype male: Total length 0.98. Carapace 0.49 long, 0.45 wide. Abdomen 0.65 long, 0.49 wide. Leg I femur 0.86. Cephalothorax tan yellow; legs pale tan-yellow; abdomen pale cream. Carapace raised anteriorly, fused to sternum via pleural sclerites; dorsal surface of pars cephalica strongly convex in lateral view; carapace and sternum heavily punctate. Eyes absent, except for single, barely-visible vestigial eye spot on each side of pars cephalica. Chelicerae each with large, bulging anterior projection; promargin without peg teeth. Legs relatively long (leg I femur- carapace ratio 1.76); macrosetae absent. Abdomen globose, covered with hair-like setae, each seta projecting from small sclerotic spot; dorsal scute and lateral sclerotic strips absent. Pedipalpal patella with retrolaterally-directed, hooked lRPA and strongly recurved distal apophysis bearing flattened distal process; tibia without thorn-like macrosetae; tegulum smooth, with curved, marginal ETR; embolus very long (length >> 5× width), coiling nearly 2× around margin of bulb (Fig. 181).

Allotype female: Total length 1.07. Carapace 0.55 long, 0.47 wide. Abdomen 0.73 long, 0.59 wide. Leg I femur 0.87. Cephalothorax, abdominal sclerites dark tan-yellow; legs, abdomen pale tan-yellow. Carapace raised anteriorly, fused to sternum via pleural sclerites; dorsal surface of pars cephalica strongly convex in lateral view; carapace and sternum heavily punctate. Eyes absent, except for single, barely-visible vestigial eye spot on each side of pars cephalica. Chelicerae each with large, bulging anterior projection; promargin without peg teeth. Legs relatively long (leg I femur-carapace ratio 1.58); macrosetae absent. Abdomen subtriangular-globose, covered with hair-like setae, each seta projecting from small sclerotic spot; dorsal scute and lateral sclerotic strips absent. Pedipalp entire, five-segmented. Epigyne with distinctive, inverted L-shaped external morphology (Fig. 180D); receptacula globular, constricted, with looped internal ducts; insemination ducts coiled around receptacula; fertilisation ducts simple, curved (Fig. 178D).

Distribution. Known only from the cave Wargata Mina (formerly Judds Cavern) in the Cracroft karst of southern Tasmania (Fig. 213).

Remarks. Olgania cracroft is a distinctive, blind and long-legged species known only from a single cave in southern Tasmania. It is among the most troglomorphic of any Micropholcommatidae , and is most similar to O. troglodytes from the nearby Ida Bay karst (Fig. 179). Nothing is known of its biology or conservation status, except that specimens were collected from sheet-webs on the cave wall.