Ischnothyreus meidamon, Edward & Harvey, 2014

Edward, Karen L. & Harvey, Mark S., 2014, Australian Goblin Spiders Of The Genus Ischnothyreus (Araneae, Oonopidae), Bulletin of the American Museum of Natural History 2014 (389), pp. 1-144 : 30-32

Ischnothyreus meidamon , new species Figures 11–12 , map 5

TYPES: AUSTRALIA: Queensland: Male holotype, female allotype, and three female paratypes from 3 km NNE Mount Webb, 15.05 ° S, 145.15 ° E (1–3 Oct 1980, T. Weir), deposited in ANIC (³ holotype: PBI _ OON 00005887 ; ♀ allotype and paratypes: PBI _ OON 00005595 ) .

ETYMOLOGY: The specific epithet is derived from the Greek meidemon meaning ‘‘smiling’’ ( Brown, 1956), and relates to the smile-shaped epigynal atrium of the female, which comes to sharp points at the lateral edges.

DIAGNOSIS: Males of this species can be distinguished by the distal tip of the embolic region of the palp, which is angled backward toward the cymbium, distally broad and short, extending about 1/3 length of the bulb (fig. 12A, B). The female epigynal region has an epigynal atrium that is wider than high, smile shaped with sharp lateral points, and lacking heavily sclerotized processes (figs. 11I, 12F).

MALE (PBI_OON 5887, figs. 11A–C, G, H, 12A–E). Total length 1.46. CEPHALO- THORAX: Carapace pale orange, broadly oval in dorsal view, pars cephalica strongly elevated in lateral view, anteriorly narrowed to 0.49 times its maximum width or less, anterolateral corners without extension or projections, surface of elevated portion of pars cephalica smooth, sides finely reticulate. Clypeus margin unmodified, curved downward in front view, low, ALE separated from edge of carapace by less than their radius; setae light. Eyes: ALE largest, ALE circular, PME oval, PLE oval; posterior eye row straight from above; ALE touching, ALE- PLE touching. Sternum longer than wide, pale orange, uniform; setae light, evenly scattered. Chelicerae, endites, and labium pale orange. Chelicerae slightly divergent, anterior face unmodified; promargin with one larger denticle; fang shape normal, without prominent basal process; setae light. Labium elongated hexagon, not fused to sternum, anterior margin indented at middle, same as sternum in sclerotization; with six or more setae on anterior margin. Endites anteromedian tip with one strong, toothlike projection, same as sternum in sclerotization. ABDOMEN: Ovoid; dorsum soft portions white. Book lung covers elliptical. Dorsal scutum pale orange, covering more than 3/4 of abdomen, between 1/4 and 1/2 abdomen width, middle surface smooth, sides smooth. Epigastric scutum small lateral sclerites absent. Postepigastric scutum yellow, covering about 2/3 of abdominal length. Dorsum, epigastric area, and postepigastric area setae light. LEGS: Pale orange, without color pattern; patella plus tibia I shorter than carapace. Leg spination: femora: I p0-2-0; II p0-1-0; tibiae: I, II p2-2-0; v2-2-0; metatarsi: I, II p1-1-0; v1-1-0. GENITALIA: Palp proximal segments dark red-brown; embolus dark; femur shorter than trochanter; patella longer than femur; cymbium dark red-brown, without distal patch of setae; bulb dark redbrown, 1 to 1.5 times as long as cymbium, stout; embolic region angled backward toward cymbium, broad and short, extends 1/3 length of palpal bulb (fig. 12A, B).

FEMALE (PBI_OON 5595, figs. 11D–F, I, 12F). Total length 1.50. CEPHALOTHO- RAX: Carapace pars cephalica slightly elevated in lateral view. Eyes: posterior eye row procurved from above. ABDOMEN: Dorsal scutum covering 1/2 to 3/4 of abdomen. Epigastric scutum small lateral sclerites present. Postepigastric scutum pale orange, widely hexagonal, covering about 1/3 of the abdominal length. LEGS: Leg spination: femora: I p0-2-0; II p0-1-0; tibiae: I, II p2- 2-0; v2-2-0; metatarsi: I, II p1-1-0; v1-1-0. GENITALIA: Ventral view: epigynal atrium wider than high, smile shaped with sharp lateral points, heavily sclerotized processes absent; convoluted duct much thicker than apodemes (figs. 11I, 12F).

OTHER MATERIAL EXAMINED: AUS- TRALIA: Queensland: 2.0 km WNW Cape Tribulation. Site 2, rainforest, 50 m, 16.08333 ° S, 145.43330 ° E, Sept. 23–Oct. 07, 1982 (G. Monteith, D. Yeates, G. Thompson, QM S16038 , PBI _OON 25739), 1 ³ ; Cape Tribulation, Pilgrim Sands , rainforest, 5 m, 16.08333 ° S, 145.43330 ° E, Aug. 24–29, 1988 (R. Raven, J. Gallon, T. Churchill, QM S14036 , PBI _OON 25814), 1 ³ ; Cedar Bay National Park, Bloomfield Road , rainforest, leaf litter, 15.79638 ° S, 145.30194 ° E, May 12, 2009 (K. Edward and P. Cullen, QM S95911 , PBI _ OON 5543 ), 2 ♀ ; Moses Creek , 4 km NE of Mount Finnigan, rainforest, leaf litter, 15.78333 ° S, 145.28333 ° E, Oct. 14–16, 1980 (T.A. Weir, ANIC, PBI _OON 25821), 3 ³, 3 ♀ ; Moses Creek , 4 km NE of Mount Finnigan, rainforest, leaf litter, 15.78333 ° S, 145.28333 ° E, Oct. 14–16, 1980 (T.A. Weir, ANIC, PBI _ OON 25823), 1 ³, 2 ♀ ; Mount Webb National Park , rainforest, leaf litter, 200 m, 15.06666 ° S, 145.11666 ° E, Sept. 28–30, 1980 (T.A. Weir, ANIC, PBI _OON 25868), 2 ³, 1 ♀ ; Mount Webb , 3 km NNE, rainforest, leaf litter, 15.05000 ° S, 145.15000 ° S, Apr. 30–May 03, 1981 (A. Calder, J. Freehan, ANIC, PBI _ OON 25741), 1 ³, 2 ♀ .

DISTRIBUTION: This species is known only from the northern subregions of the Wet Tropics Bioregion (CL, FU, TU, and TL), in northeastern Queensland (map 5).

Figures

Fig. 11. Ischnothyreus meidamon, sp. nov. Holotype male (PBI_OON 00005887): A. habitus, dorsal view; B. habitus, ventral view; C. habitus, lateral view; G. carapace, anterior view; H. sternum, ventral view. Allotype female (PBI_OON 00005595): D. habitus, dorsal view; E. habitus, ventral view; F. habitus, lateral view; I. epigynum, ventral view.

Fig. 12. Ischnothyreus meidamon, sp. nov. Holotype male (PBI_OON 00005887): A. left palp, prolateral view; B. left palp, retrolateral view; C. left chelicerae, anterior view; D. left chelicerae, posterior view; E. left palp, dorsal view. Allotype female (PBI_OON 00005595): F. epigynum, ventral view. Scale lines 5 0.1 mm.