Misgolas milledgei, Wishart & Rowell, 2008

Wishart, Graham & Rowell, David M., 2008, Trapdoor Spiders of the Genus Misgolas (Mygalomorphae: Idiopidae) from Eastern New South Wales, With Notes on Genetic Variation, Records of the Australian Museum 60 (1), pp. 45-86 : 81-83

Misgolas milledgei n.sp.

Fig. 23A–H

Type material. HOLOTYPE?, AM KS21570 , Bondi, Eastern suburb of Sydney, (33°53'S 151°17'E), 4 Apr. 1989, J.Weiss, found wandering in house.

Diagnosis. In male: Large sized dark brown spider, carapace length c. 8.5–9, retrodorsal surface of metatarsus IV without spines ( Fig. 23G ); venter pale with dark brown maculations in median and a transverse bands ( Fig. 23E ). Spines absent on tarsi I–III, row of 2–3 on proventral surface tarsi IV ( Fig. 23F ). Palpal bulb retrolateral embolic flange with c. 8 distinct folds; embolus as figured ( Fig. 23B,C ). Cymbium dorsal surface with many crowded short blunt sub-erect spines ( Fig. 23H ). Conformation of palpal tibia as figured ( Fig. 23A ). Female not known.

Description

Male holotype ( Fig. 23A–H ). Size. Carapace length 8.72, width 7.06. Abdomen length 7.74, width 5.29. Colour. In alcohol carapace, limbs and chelicerae dark brown; darker brown limb smudges absent. Carapace and limbs with few sparse golden hairs. Abdomen dorsum dark brown with c. 6 pallid transverse chevrons ( Fig. 23D ). Venter pallid with some dark brown maculations forming median and central transverse bands ( Fig. 23E ). Carapace. (Right anterior segment of carapace damaged) Edge fringed with black bristles which encroach onto posterior quarter of post foveal surface. Few weak black inter-strial bristles. Row of c. 16 black bristles on caput arch; 11 between PME; 21 on clypeus. Weakly chitinized area on pleuron membrane below clypeus with 3 bristles and few fine setae. Fovea width 1.69, recurved, posterior wall centrally divided by minute pitted intrusion. Eyes. Raised on mound. Ocular area darker adjacent to eyes. Anterior width 1.36, posterior width 1.25, length 0.77, width/length ratio 1.77. Line joining posterior edges of ALE bisects AME. Posterior row straight in front, recurved behind. Chelicerae. Rastellum first row 7(6) strong spines, few smaller spines scattered behind. Intercheliceral tumescence small, indistinct. Fang groove with 9(9) promarginal teeth, 9(12) smaller retromarginal/intermediate row teeth. Labium. Bulbous, length 1.05, width 1.31. Labiosternal suture narrowed medially, continuous. Maxillae c. 12(16) reduced or elementary anteroental cuspules appearing as thickened setae. Sternum. Length 4.42, width 3.68. Sigilla first and second pair small, round; third pair larger, ovate; first pair one diameter from margin, second pair twice its diameter from margin, third pair twice its length from margin. Legs. Tibia I with distal bifid apophysis; distal process with 2(2) blunt compact spines, proximal process with row of 3(3) longer pointed compact spines.

palp I II III IV femur 4.42 7.37 6.63 5.34 7.18 patella 2.49 3.99 3.62 2.95 3.62 tibia 3.56 4.85 4.42 4.18 5.83 metatarsus — 5.77 4.91 4.24 6.39 tarsus 1.66 3.19 3.01 2.58 3.07 total 12.13 25.17 22.59 19.29 26.09

Palp ( Fig. 23A ). Cymbium with many crowded short blunt sub-erect spines distributed on distal four-fifths of d surface. RTA short, pointed; d surface covered with short pointed spines which continue uninterrupted along rv edge of tibial excavation terminating at DTA end. DTA straight, inclined downwards. TEM prominent, pallid, adjacent to RTA, pl surface with indistinct TET. Bulb ( Fig. 23B,C ). Embolic rl flange with 8 distinct folds; margin straight. Embolus tip with pl bend from d aspect, suspending thin translucent flange from pl aspect. Embolic apophysis absent. Scopula. Complete on tarsi I and II; weaker, incomplete on metatarsi I and II; weaker, complete on tarsi III and IV; sparse distal remnants on metatarsi III and IV. Trichobothria. Palp: tarsi 9, tibia pd 5, rd 5. Leg I: tarsi 12, metatarsi 15, tibia pd 7, rd 7. Leg II: tarsi 11, metatarsi 13, tibia pd 6, rd 6. Leg III: tarsi 10, metatarsi 8, tibia pd 4, rd 7. Leg IV: tarsi 13, metatarsi 17, tibia pd 7, rd 7. Leg spination. Leg I: metatarsi rv 0100; tibia v 0112. Leg II: metatarsi rv 01101; tibia v 01102. Leg III: metatarsi pv 011, rv 010, pd 011110, rd 001110; tibia v 0113; patella pd 8. Leg IV: tarsi pv 0110(01110); metatarsi v 011212; tibia 0222. Abdomen. Dorsum with dense cover of erect long dark brown bristles; venter with dense cover of weak, short, sub-erect brown bristles.

Remarks. This holotype specimen was earlier erroneously thought to have been collected from the Bondi State Forest (S.E. N.S.W.). It is the only example of the species presently known. It is extraordinary that more have not been collected during the long period that the Bondi urban area of Sydney has been densely settled. Albeit this phenomenon is shared by the recently described M. wayorum Wishart, 2006 and is additional to the eleven known species found from the Sydney region ( Wishart, 2006). The conformation of the specimen precludes it being conspecific with M. maculosus (Rainbow & Pulleine, 1918) .

Etymology. The species is named in recognition of arachnologist and curator of arachnids at the Australian Museum, Graham Milledge.

Distribution and natural history. The spider is known only from the type locality, the Sydney seaside suburb of Bondi. That a few grains of sand are retained in the fovea of this specimen and Bondi being a sandstone locality supports the integrity of the type locality report.

Figures

Fig. 23. Misgolas milledgei n.sp. A–H?, holotype AM KS21570: (A), right palp retrolateral. (B,C), right bulb: B, dorsal; C, prolateral. (D), body dorsum. (E), venter. (F,G), right leg IV: F, prolateral; G, retrolateral. (H), right cymbium dorsal.