Zephyrarchaea vichickmani Rix & Harvey

Rix, Michael G. & Harvey, Mark S., 2012, Australian Assassins, Part II: A review of the new assassin spider genus Zephyrarchaea (Araneae, Archaeidae) from southern Australia, ZooKeys 191, pp. 1-62 : 18-19

Zephyrarchaea vichickmani Rix & Harvey sp. n. Figs 1A8B9A1626

Central Highlands Assassin Spider

Type material.

Holotype male: Yarra Ranges National Park, Acheron Gap, Victoria, Australia, 37°40'37"S, 145°44'24"E, sifting elevated leaf litter under tree ferns, Nothofagus rainforest, 769 m, 29.III.2010, M. Rix (MV K11578).

Paratypes: Allotype female, same data as holotype (MV K11579); 1 female and 6 juveniles, same data as holotype (WAM T112583DNA: Ar14 –49-F/Ar14–133-J/Ar14– 134-J).

Other material examined.

AUSTRALIA: Victoria:Yarra Ranges National Park: Acheron Gap, Central Highlands, 6 km NE. of Mount Donna Buang, 37°40'43"S, 145°44'20"E, pitfall trap, Nothofagus cunninghamii forest, 25.VI.-29.VIII.1996, G. Milledge, 1♀ (MV K5919); same data except 21.II.-23.IV.1996, 1 juvenile (MV K5920).

Etymology.

The specific epithet is a patronym in honour of the late Professor Victor Hickman, for his extraordinary contributions to arachnology and in honour of L. S. Butler’s original (1929) patronym.

Diagnosis.

Zephyrarchaea vichickmani can be distinguished from other known congeners except Zephyrarchaea marae sp. n. by the absence of a proximal tuft or brush on the male chelicerae (Fig. 16C); and from Zephyrarchaea marae sp. n. by the less sinuous shape of conductor sclerite 2 (C2) (Figs 16 D–E) and the more concave anterior margin of the male diastema adjacent to the ‘neck’ (Fig. 16B). Females further distinguished from other known congeners except Zephyrarchaea marae sp. n. by the combination of a spherical abdomen (Fig. 16A), strongly concave post-ocular depression in lateral view (Fig. 9A), and moderately elevated ‘head’ dorsally (post-ocular ratio ≥ 0.25) (Fig. 9A).

This species can also be distinguished from other genotyped taxa (see Fig. 3) by the following 16 unique nucleotide substitutions for COI and COII (n = 3): C(24), G(54), G(216), G(309), A(360), A(393), C(702), G(795), T(951), A(976), A(1059), T(1063), A(1200), G(1281), C(1479), T(1596), and can be further distinguished from all other Australian Archaeidae except Zephyrarchaea marae by the absence of a COII amino acid residue at positions 1441-1443.

Description.

Holotype male: Total length 2.77; leg I femur 1.80; F1/CL ratio 1.67. Cephalothorax dark reddish-brown; legs tan brown with darker annulations; abdomen mottled grey-brown and beige, with reddish-brown dorsal scute and sclerites (Fig. 16B). Carapace relatively short (CH/CL ratio 1.69); 1.08 long, 1.82 high, 1.01 wide; ‘neck’ 0.59 wide; highest point of pars cephalica (HPC) near posterior third of ‘head’ (ratio of HPC to post-ocular length 0.64), carapace with pronounced concave depression anterior to HPC; ‘head’ moderately elevated dorsally (post-ocular ratio 0.28) (Fig. 8B). Chelicerae with short comb of accessory setae on anterior face of paturon (Fig. 16C). Abdomen 1.59 long, 1.10 wide; almost spherical in lateral profile, without dorsal hump-like tubercles; dorsal scute fused anteriorly to epigastric sclerites, extending posteriorly to cover anterior two-thirds of dorsal abdomen. Unexpanded pedipalp (Figs 16 D–F) bulbous, almost spherical, with gently curved, tapering embolus supported by conductor sclerites 1-2; tegular sclerite 1 (TS 1) strongly curved, claw-like in prolateral view, with twisted, flattened and rounded apex; TS 2-3 projecting well beyond retro-distal rim of tegulum.

Allotype female: Total length 3.90; leg I femur 2.08; F1/CL ratio 1.76. Cephalothorax dark reddish-brown; legs tan brown with darker annulations; abdomen mottled grey-brown and beige (Fig. 16A). Carapace relatively short (CH/CL ratio 1.83); 1.18 long, 2.15 high, 1.12 wide; ‘neck’ 0.69 wide; highest point of pars cephalica (HPC) approaching posterior third of ‘head’ (ratio of HPC to post-ocular length 0.61), carapace with pronounced concave depression anterior to HPC; ‘head’ moderately elevated dorsally (post-ocular ratio 0.26) (Fig. 9A). Chelicerae without accessory setae on anterior face of paturon. Abdomen 2.51 long, 1.92 wide; spherical in lateral profile, without dorsal hump-like tubercles. Internal genitalia (Fig. 16G) with cluster of ≤ 15 sausage-shaped spermathecae fanning out either side of gonopore, clusters widely separated along midline of genital plate; outermost (posterior) spermatheca on each side stalked, distally spherical.

Variation: Females (n = 3): total length 3.44-3.90; carapace length 1.14-1.18; carapace height 2.00-2.15; CH/CL ratio 1.75-1.83.

Distribution and habitat.

Zephyrarchaea vichickmani is known only from temperate Nothofagus rainforest habitats in the Victorian Central Highlands, north-east of Melbourne (Fig. 26).

Conservation status.

This species has an imperfectly known distribution, and although potentially restricted, the abundance of protected forested habitats near the type locality would suggest that the species is unlikely to be of conservation concern.