Zephyrarchaea marki 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 : 13-14

Zephyrarchaea marki Rix & Harvey sp. n. Figs 1D4B8H1222

Cape Le Grand Assassin Spider

Type material.

Holotype male: Cape Le Grand National Park, Thistle Cove, Western Australia, Australia, 33°59'55"S, 122°11'59"E, sifting elevated leaf litter in Banksia speciosa thicket behind beach, 5.VI.2010, M. Rix (WAM T118985).

Paratypes: 1 male and 1 juvenile, same data as holotype (WAM T114033DNA: CLG-146-J).

Other material examined.

AUSTRALIA: Western Australia:Cape Le Grand National Park: Thistle Cove, 33°59'54"S, 122°12'01"E, sifting elevated leaf litter, Banksia speciosa thicket behind beach, 28.VII.2009, M. Rix, M. Wojcieszek, 3 juveniles (WAM T94477DNA: CLG-144-J/CLG-145-J).

Etymology.

The specific epithet is a patronym in honour of Mark Wojcieszek, for helping to discover the first specimens of this species at Cape Le Grand National Park in 2009.

Diagnosis.

Zephyrarchaea marki can be distinguished from Zephyrarchaea janineae and Zephyrarchaea mainae by the absence of dorsal hump-like tubercles on the abdomen (Fig. 12A); from Zephyrarchaea marae sp. n. and Zephyrarchaea vichickmani sp. n. by the presence of a proximal tuft of accessory setae on the male chelicerae (Fig. 12B); from Zephyrarchaea barrettae sp. n. and Zephyrarchaea melindae sp. n. by the shape of tegular sclerites 2-3, which project well beyond the retro-distal rim of the tegulum (Figs 12 C–D); and from Zephyrarchaea porchi sp. n. by the larger, more protuberant proximal bulge on the male chelicerae (Fig. 12B).

This species can also be distinguished from other genotyped taxa (see Fig. 3) by the following nine unique nucleotide substitutions for COI and COII (n = 3): A(147), T(204), C(300), C(306), G(495), C(804), G(807), G(1491), A(1548).

Description.

Holotype male: Total length 2.77; leg I femur 2.00; F1/CL ratio 1.95. Cephalothorax dark reddish-brown; legs tan brown with darker annulations; abdomen mottled grey-brown and beige, with reddish-brown dorsal scute and sclerites (Fig. 12A). Carapace short (CH/CL ratio 1.65); 1.03 long, 1.69 high, 1.00 wide; ‘neck’ 0.56 wide; highest point of pars cephalica (HPC) approaching posterior third of ‘head’ (ratio of HPC to post-ocular length 0.62), carapace with pronounced concave depression anterior to HPC; ‘head’ not strongly elevated dorsally (post-ocular ratio 0.21) (Fig. 8H). Chelicerae with proximal tuft and additional comb of accessory setae on anterior face of paturon (Fig. 12B). Abdomen 1.64 long, 1.13 wide; almost spherical in lateral profile, without dorsal hump-like tubercles but with highly recumbent mound-like vestiges; dorsal scute fused anteriorly to epigastric sclerites, extending posteriorly to cover nearly anterior two-thirds of dorsal abdomen. Unexpanded pedipalp (Figs 12 C–E) pyriform, with broad, distally curved embolus supported by conductor sclerites 1-2; tegular sclerite 1 (TS 1) porrect, strongly curved in prolateral view, with flattened, broadly rounded, paddle-shaped apex; TS 2-3 projecting beyond retro-distal rim of tegulum.

Female: Unknown.

Variation: Males (n = 2): total length 2.77-2.79; carapace length 1.03 (invariable); carapace height 1.69 (invariable); CH/CL ratio 1.64-1.65.

Distribution and habitat.

Zephyrarchaea marki is known only from Thistle Cove at Cape Le Grand National Park, on the far south-eastern coast of Western Australia (Fig. 22). Specimens have been collected by beating and sifting elevated leaf litter in a dense coastal thicket of Banksia speciosa .

Conservation status.

This species appears to be a rare short-range endemic taxon ( Harvey 2002b), with the single known population in the Cape Le Grand National Park potentially threatened by fire, dieback disease (affecting Banksia heathland vegetation) and climate change.