Ischnothyreus tumidus, 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 : 22-26

Ischnothyreus tumidus , new species Figures 7–8 , map 3

TYPES: AUSTRALIA: Queensland: Male holotype from Cape Tribulation, 16.08333 ° S, 145.46666 ° E (20–29 July 1992, R. Forster), deposited in QM ( S78176 , PBI_OON 00022791). Female allotype from 1.5 km NW Cape Tribulation (Site 1), 16.08333 ° S, 145.4667 ° E, 1 m (23 Sept. 1982, G. Monteith, D. Yeates, G. Thompson), deposited in QM ( S16068 , PBI_OON 00025962).

ETYMOLOGY: The specific epithet is derived from the Latin tumidus meaning ‘‘swelling’’ ( Brown, 1956), and refers to the distinct subdistal swelling on the fang of the male of this species.

DIAGNOSIS: Males of this species possess a uniquely shaped cheliceral fang, which is subdistally and basally swollen (fig. 8C, D). The clypeus, hyaline grooves, anterolateral corners of the carapace, endites, and the lateral edges of the labium are all heavily sclerotized (fig. 7G–H). Females can be distinguished by the two heavily sclerotized lobes or processes overhanging the anterior portion of an ovoid epigynal atrium, and a weak horizontal sclerotization connected to the posteriorly directed lateral apodemes (figs. 7I, 8F).

MALE (PBI_OON 22791, figs. 7A–C, G– H, 8 A–E). Total length 1.65. CEPHALO- THORAX: Carapace orange-brown, broadly oval in dorsal view, pars cephalica strongly elevated in lateral view, anteriorly narrowed to between 0.5 and 0.75 times its maximum width, anterolateral corners with heavily sclerotized triangular projections, surface of elevated portion of pars cephalica finely reticulate, sides strongly reticulate. Clypeus margin strongly sclerotized, straight in front view, high, ALE separated from edge of carapace by more than their radius; setae dark. 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 dark, evenly scattered. Chelicerae, endites, and labium pale orange to red-brown. Chelicerae straight, anterior face with conical apophysis, fang with enlarged subdistal and basal swelling; promargin with one much larger denticle or tooth; setae dark. Labium elongated hexagon, not fused to sternum, anterior margin indented at middle, heavy sclerotization either side; with six or more setae on anterior margin. Endites anteromedian tip with one strong, toothlike projection, much more heavily sclerotized than sternum. ABDO- MEN: Ovoid; dorsum soft portions white. Book lung covers elliptical. Dorsal scutum pale orange-brown, covering more than 3/4 of abdomen, more than 1/2 to most of abdomen width, middle surface smooth, sides smooth. Epigastric scutum small lateral sclerites absent. Postepigastric scutum pale orange, covering about 3/4 of abdominal length. Dorsum, epigastric area, and postepigastric area setae dark. 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 about as long as femur; cymbium dark red-brown; bulb dark redbrown, 1 to 1.5 times as long as cymbium, stout; embolic region of palp obtusely bent at right angle to palpal bulb, elongate, tapering to slightly pointed tip; presumed embolus opening situated in dark colored region near bend (fig. 8A).

FEMALE (PBI_OON 25962, figs. 7D–F, I, 8F). Total length 2.22. CEPHALOTHO- RAX: Carapace pars cephalica slightly elevated in lateral view. Clypeus straight in front view. Chelicerae slightly divergent. ABDO- MEN: Ovoid. Dorsal scutum covering 1/2 to 3/4 of abdomen, between 1/4 and 1/2 abdomen width. Epigastric scutum small lateral sclerites present. Postepigastric scutum short, only around epigastric furrow. 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: epigastric furrow procurved; epigynal atrium ovoid, two heavily sclerotized lobes or processes overhang anterior portion; convoluted duct thicker than apodemes, weak horizontal sclerotization connects to posteriorly directed lateral apodemes (figs. 7I, 8F).

OTHER MATERIAL EXAMINED: AUS- TRALIA: Queensland: Cape Tribulation , 1 km WNW, rainforest, 10 m, 16.04000 ° S, 145.28000 ° E, Jan. 4–Feb. 1, 1996 (L. Umback, QM S95896 , PBI _ OON 5840 ), 1 ♀ ; Cape Tribulation , rainforest, 16.08333 ° S, 145.46666 ° E, July 20–29, 1992 (R. Forster, QM S78150 , PBI _OON 22781), 3 ♀ ; Cape Tribulation , rainforest, 16.08333 ° S, 145.46666 ° E, July 20–29, 1992 (R. Forster, QM S78176 , PBI _OON 25756), 2 ♀ ; Cape Tribulation , rainforest, leaf litter, 10 m, 16.08333 ° S, 145.43330 ° E, Oct. 13, 1980 (G. Monteith, QM S12953 , PBI _OON 25767), 1 ³ ; Cape Tribulation , rainforest, leaf litter, 10 m, 16.08333 ° S, 145.43330 ° E, Oct. 13, 1980 (G. Monteith, QM S12953 , PBI _OON 25769), 1 ♀ ; Cape Tribulation, 1.5 km NW ( Site 1), rainforest, leaf litter, 1 m, 16.08333 ° S, 145.46670 ° E, Oct. 3, 1982 (G. Monteith, D. Yeates, G. Thompson, QM S16087 , PBI _OON 25768), 1 ♀ ; 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 21949), 2 ³, 2 ♀ ; Daintree National Park, Cowie range, rainforest, leaf litter, 15.98277 ° S, 145.41472 ° E, May 11, 2009 (K. Edward and P. Cullen, QM S95897 ), 1 ³, 1 ♀ ; Daintree National Park ; Cowie range, Bloomfield Road, rainforest, leaf litter ,

Map 3. Map of northeastern Queensland, northern Wet Tropics Bioregion, showing recorded distributions of Ischnothyreus tumidus (+), I. bifidus (N) and I. digitus (Z). Wet Tropics upland subregions outlined in grey (see map 1).

15.98277 ° S, 145.39638 ° E, May 11, 2009 (K. Edward and P. Cullen, QM S95898 , PBI _ OON 5540 ), 1 ♀ ; Daintree National Park ; Donovan Range , Bloomfield track N of Cape Tribulation, rainforest, leaf litter, 16.00000 ° S, 145.44750 ° E, May 11, 2009 (K. Edward and P. Cullen, QM S95899 ), 1 ³ ; Daintree National Park , Donovan Range, Bloomfield track N of Cape Tribulation, rainforest, leaf litter, 16.00000 ° S, 145.44750 ° E, May 11, 2009 (K. Edward and P. Cullen, QM S95900 , PBI _ OON 5564 ), 1 ♀ ; Home Rule Falls track, near Big Tableland National Park, rainforest, leaf litter, 15.74555 ° S, 145.29500 ° E, May 11, 2009 (K. Edward and P. Cullen, QM S95901 , PBI _ OON 5544 ), 2 ♀ ; Keating’s Gap , Mount Cook, rainforest, 15.50000 ° S, 145.23330 ° E, July 20–Nov. 28, 1992 (R. Raven, P. Lawless, E. Lawless, M. Shaw, QM S22597 , PBI _OON 21999), 1 ³ ; Mount Sorrow plateau, rainforest, leaf litter, 750 m, 16.08333 ° S, 145.43330 ° E, Dec. 10, 1993 (G. Monteith, QM S49684 , PBI _OON 22123), 1 ³ ; Pilgrim Sands (NQ 25), rainforest, 16.07000 ° S, 145.46670 ° E, Nov. 5, 1991, to July 20, 1992 (R. Raven, P. Lawless, M. Shaw, QM S24872 , PBI _OON 22034), 1 ♀ ; Pilgrim Sands (NQ 25), rainforest, 16.07000 ° S, 145.46670 ° E, July 21– Nov. 29, 1992 (R. Raven, P. Lawless, M. Shaw, QM S24045 , PBI _OON 22093), 1 ♀ ; Shiptons Flat , rainforest, leaf litter, 200 m, 15.80000 ° S, 145.25000 ° E, Nov. 30, 1985 (D.K. Yeates, QM S22734 , PBI _OON 21699), 1 ♀ .

DISTRIBUTION: This species is known from the northern subregions of the Wet Tropics Bioregion (CL, BL, FU, TU, and TL), in northeastern Queensland (map 3).

Figures

Fig. 7. Ischnothyreus tumidus, sp. nov. Holotype male (PBI_OON 00022791): A. habitus, dorsal view; B. habitus, ventral view; C. habitus, lateral view; G. carapace, anterior view; H. sternum, ventral view. Allotype female (PBI_OON 00025962): D. habitus, dorsal view; E. habitus, ventral view; F. habitus, lateral view; I. epigynum, ventral view.

Fig. 8. Ischnothyreus tumidus, sp. nov. Holotype male (PBI_OON 00022791): 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 00025962): F. epigynum, ventral view. Scale lines 5 0.1 mm.