Difference between revisions of "Zephyrarchaea grayi"

Latest revision as of 15:59, 7 May 2012

Taxonavigation

Ordo: Araneae
Familia: Archaeidae
Genus: Zephyrarchaea

Name

Zephyrarchaea grayi Rix & Harvey sp. n. – Wikispecies link – ZooBank link – Pensoft Profile

Vernacular name

Grampians Assassin Spider

Type material

Holotype female: Grampians National Park, Delley’s Dell, Silverband Road, Victoria, Australia, sweeping at night, 26.III.1974, M. Gray (AMS KS109448).

Etymology

The specific epithet is a patronym in honour of Dr Mike Gray, for his contributions to arachnology and for first discovering this species in the Grampians National Park.

Diagnosis

Females of Zephyrarchaea grayi can be distinguished from Zephyrarchaea janineae and Zephyrarchaea mainae by the absence of dorsal hump-like tubercles on the abdomen (Fig. 19A); from Zephyrarchaea barrettae, Zephyrarchaea melindae and Zephyrarchaea robinsi by the strongly concave post-ocular depression in lateral view (Fig. 9C); from Zephyrarchaea austini sp. n. by the larger body size (carapace length > 1.10) and taller carapace (CH/CL ratio ≥ 1.70) (Figs 7, 19A); and from Zephyrarchaea marae and Zephyrarchaea vichickmani by the shape of the ‘head’, which is less elevated dorsally (post-ocular ratio < 0.25) and with the highest point of the pars cephalica (HPC) closer to the middle of the head (ratio of HPC to post-ocular length < 0.60) (Fig. 9C).

Description

Holotype female: Total length 3.36; leg I femur 1.95; F1/CL ratio 1.73. Cephalothorax dark reddish-brown; legs tan brown with darker annulations; abdomen mottled grey-brown and beige (Fig. 19A). Carapace relatively short (CH/CL ratio 1.72); 1.13 long, 1.94 high, 1.03 wide; ‘neck’ 0.63 wide; highest point of pars cephalica (HPC) approaching middle of ‘head’ (ratio of HPC to post-ocular length 0.57), carapace with pronounced concave depression anterior to HPC; ‘head’ not strongly elevated dorsally (post-ocular ratio 0.23) (Fig. 9C). Chelicerae without accessory setae on anterior face of paturon. Abdomen 1.85 long, 1.36 wide; spherical in lateral profile, without dorsal hump-like tubercles. Internal genitalia (Fig. 19B) with cluster of ≤ 15 sausage-shaped spermathecae fanning out either side of gonopore, clusters widely separated along midline of genital plate; outermost (posterior) spermathecae bulbous distally.
Male: Unknown.

Distribution and habitat

Zephyrarchaea grayi is known only from wet eucalypt forest at Delley’s Dell, in the Grampians National Park of western Victoria (Fig. 29).

Conservation status

This species appears to be a rare short-range endemic taxon (Harvey 2002b^[1]), with the single known population in the Grampians National Park potentially threatened by fire and climate change. Targeted searching at the type locality in March 2010 failed to reveal new specimens of this species, and the site had been recently burnt.

Original Description

• Rix, M; Harvey, M; 2012: Australian Assassins, Part II: A review of the new assassin spider genus Zephyrarchaea (Araneae, Archaeidae) from southern Australia ZooKeys, 191: 1-62. doi

Images

Figure 7. Graphs depicting the relationship between carapace length (CL) and carapace height (CH) for species of Zephyrarchaea. Smaller grey dots denote species of Austrarchaea (see Rix and Harvey 2011[2]); boxes denote the three lineages of Zephyrarchaea from Victoria/South Australia, the Stirling Range and elsewhere in southern Western Australia.   Figure 9. Lateral ‘head’ profiles of females of species of Zephyrarchaea, showing variation in carapace shape as quantified by the post-ocular ratio (P.O. Ratio) and ratio of highest point of carapace relative to post-ocular length (HPC Ratio) (see Fig. 8): A, allotype Zephyrarchaea vichickmani sp. n.; B, allotype Zephyrarchaea marae sp. n.; C, holotype Zephyrarchaea grayi sp. n.; D, holotype Zephyrarchaea austini sp. n.; E, Zephyrarchaea mainae (Platnick, 1991b); F, allotype Zephyrarchaea janineae sp. n.; G, holotype Zephyrarchaea robinsi (Harvey, 2002a); H, allotype Zephyrarchaea melindae sp. n.; I, allotype Zephyrarchaea barrettae sp. n.  Figure 19. Zephyrarchaea grayi sp. n. and Zephyrarchaea austini sp. n. A–B, holotype female Zephyrarchaea grayi sp. n. (AMS KS109448) from Delley’s Dell, Grampians National Park, Victoria: A, cephalothorax and abdomen, lateral view; B, internal genitalia, antero-dorsal view. C–D, holotype female Zephyrarchaea austini (SAM NN28000) from Western River Wilderness Protection Area, Kangaroo Island, South Australia: C, cephalothorax and abdomen, lateral view; D, internal genitalia, antero-dorsal view. GP = genital plate. Scale bars: A, C = 1.0 mm.  Figure 29. Zephyrarchaea grayi sp. n., distribution and habitat: A, topographic map showing the known distribution of Archaeidae in Victoria and South Australia, with collection localities for Zephyrarchaea grayi highlighted in yellow; B, satellite image showing detail of inset (A); C, wet sclerophyll forest at the type locality – Delley’s Dell, Grampians National Park, Victoria (March 2010). Image (C) by M. Rix.

Other References

1. ↑ Harvey M (2002b) Short-range endemism among the Australian fauna: some examples from non-marine environments. Invertebrate Systematics 16: 555-570. doi: 10.1071/IS02009
2. ↑ Rix M, Harvey M (2012) Phylogeny and historical biogeography of ancient assassin spiders (Araneae: Archaeidae) in the Australian mesic zone: evidence for Miocene speciation within Tertiary refugia. Molecular Phylogenetics and Evolution 62: 375-396. doi: 10.1016/j.ympev.2011.10.009