Austrarchaea monteithi Gibraltar Range Assassin Spider Rix & Harvey

Rix, Michael G. & Harvey, Mark S., 2011, Australian Assassins, Part I: A review of the Assassin Spiders (Araneae, Archaeidae) of mid-eastern Australia, ZooKeys 123, pp. 1-100 : 26-27

Austrarchaea monteithi Gibraltar Range Assassin Spider Rix & Harvey sp. n. Figs 5F7F9A1937

Type material.

Holotype male: Gibraltar Range National Park, World Heritage Walk, off Gwydir Highway, near Richardsons Creek, New South Wales, Australia, 29°29'23"S, 152°19'47, sifting elevated leaf litter, subtropical rainforest, 1061 m, 20.IV.2010, M. Rix, D. Harms (AMS KS114977).

Paratype: Allotype female, same data as holotype (AMS KS114976DNA: Ar52-92-F).

Other material examined.

AUSTRALIA: New South Wales: Gibraltar Range National Park: same data as holotype, 2 juveniles (WAM T112570DNA: Ar52-93-J/Ar52-94-J); "Gibraltar Range", pyrethrum, rainforest, 30.III.1980, G. Monteith, 1 juvenile (QMB S30824).

Etymology.

The specific epithet is a patronym in honour of Dr Geoff Monteith, for first discovering this species in the Gibraltar Range National Park.

Diagnosis.

Austrarchaea monteithi can be distinguished from all other Archaeidae from mid-eastern Australia by the presence of only five dorsal hump-like tubercles on the abdomen (Fig. 5F).

This species can also be distinguished from other genotyped taxa from mid-eastern Australia (see Fig. 3B) by the following 29 unique nucleotide substitutions for COI and COII (n = 3): G(81), T(93), A(243), C(300), C(360), C(396), A(597), A(957), C(993), G(1008), C(1115), A(1212), G(1216), T(1217), T(1220), A(1221), G(1229), G(1231), T(1233), G(1275), C(1369), A(1390), G(1391), G(1414), T(1453), G(1509), A(1525), G(1526), G(1554).

Description.

Holotype male: Total length 3.13; leg I femur 2.91; F1/CL ratio 2.58. Cephalothorax dark reddish-brown; legs tan-brown with darker annulations; abdomen mottled grey-brown and beige, with darker reddish-brown dorsal scute and sclerites (Fig. 19B). Carapace tall (CH/CL ratio 2.07); 1.13 long, 2.33 high, 1.05 wide; ‘neck’ 0.53 wide; bearing two pairs of rudimentary horns; highest point of pars cephalica (HPC) near middle of ‘head’ (ratio of HPC to post-ocular length 0.54), carapace with concave depression posterior to HPC; ‘head’ not strongly elevated dorsally (post-ocular ratio 0.25) (Fig. 9A). Chelicerae with short brush of accessory setae on anterior face of paturon (Fig. 19C). Abdomen 1.69 long, 1.10 wide; with five dorsal hump-like tubercles (HT 1-5), HT1-4 arranged in two pairs; dorsal scute fused anteriorly to epigastric sclerites, extending posteriorly to first pair of hump-like tubercles; HT 3-5 each covered by separate dorsal sclerites. Unexpanded pedipalp (Figs 19D-F) with stout, almost spherical bulb and thin, strongly hooked conductor; embolic sclerite with broad, looped proximal portion extending for entire length of conductor; tegular sclerite 1 (TS 1) relatively short, filiform, obscured by conductor in retrolateral view; TS 2 spur-like, longer than TS 1; TS 2a sinuous, largely obscured by TS 2; TS 3 embedded proximally within distal haematodocha, with sharply-pointed apex projecting ventrally beyond retro-distal rim of tegulum.

Allotype female: Total length 3.38; leg I femur 3.08; F1/CL ratio 2.31. Cephalothorax dark reddish-brown; legs tan-brown with darker annulations; abdomen mottled grey-brown and beige (Fig. 19A). Carapace tall (CH/CL ratio 2.12); 1.33 long, 2.82 high, 1.21 wide; ‘neck’ 0.66 wide; bearing two pairs of rudimentary horns; highest point of pars cephalica (HPC) near middle of ‘head’ (ratio of HPC to post-ocular length 0.55), carapace with concave depression posterior to HPC; ‘head’ not strongly elevated dorsally (post-ocular ratio 0.23) (Fig. 7F). Chelicerae without accessory setae on anterior face of paturon. Abdomen 1.85 long, 1.44 wide; with five dorsal hump-like tubercles (HT 1-5), HT1-4 arranged in two pairs (Fig. 5F). Internal genitalia with cluster of ≤ 12 variably shaped spermathecae on either side of gonopore, clusters widely separated along midline of genital plate (Fig. 19G); innermost (anterior) spermathecae longest; other spermathecae variably pyriform, straight, directed antero-laterally.

Distribution and habitat.

Austrarchaea monteithi is known only from subtropical rainforest habitats in the Gibraltar Range National Park of north-eastern New South Wales (Fig. 37).

Conservation status.

This enigmatic species has an imperfectly known distribution, and although potentially restricted, appears to be relatively abundant within the World Heritage-listed Gibraltar Range National Park near Richardsons Creek (M. Rix, pers. obs.). It is not considered to be of conservation concern.