Difference between revisions of "Austrarchaea mcguiganae"

Latest revision as of 15:59, 15 August 2011

Taxonavigation

Ordo: Araneae
Familia: Archaeidae
Genus: Austrarchaea

Name

Austrarchaea mcguiganae Rix & Harvey sp. n. – Wikispecies link – ZooBank link – Pensoft Profile

Type material

Holotype male: Monga National Park, Link Road, New South Wales, Australia, 35°34'04"S, 149°54'14"E, 16.III.1999, L. Wilkie, R. Harris, H. Smith (AMS KS62790).
Paratypes: Allotype female, Monga National Park, off Link Road, New South Wales, Australia, 35°34'03"S, 149°54'15"E, sifting elevated leaf litter, complex eucalypt forest with thick understory near tree fern gully, 864 m, 6.IV.2010, M. Rix, D. Harms (AMS KS114975); 1 female and 5 juveniles, same data (WAM T112567DNA: Ar28-47-J/Ar28-128-J).

Additional material examined (of tentative identification)

AUSTRALIA: New South Wales: Deua National Park: Coondella Fire Trail, 35°58'44"S, 149°53'05"E, 11.III.1999, J. Tarnawski, S. Lassau, 1♀ (AMS KS62791). Badja State Forest: Badja Fire Trail, 36°07'30"S, 149°31'37"E, 13.III.1999, J. Tarnawski, S. Lassau, 1 juvenile (AMS KS62792); off Peters Road, near junction with Badja Forest Road, 36°07'38"S, 149°31'36"E, sifting elevated leaf litter, complex eucalypt forest with thick understory, 1075 m, 5.IV.2010, M. Rix, D. Harms, 14 juveniles (WAM T112577DNA: Ar27-129-J/Ar27-130-J/Ar27-131-J).

Etymology

The specific epithet is a patronym in honour of the late Margaret McGuigan (1920–2010), for her love of the Southern Highlands, and for a lifetime of kindness and support to the senior author.

Diagnosis

Austrarchaea mcguiganae can be distinguished from all other Archaeidae from mid-eastern Australia by the relatively short, rod-like, proximally-widened tegular sclerite 1 (TS 1) (Figs 27D-E) combined with the long brush of accessory setae on the male chelicerae (Fig. 27C).
This species can also be distinguished from other genotyped taxa from mid-eastern Australia (see Fig. 3B) by the following seven unique nucleotide substitutions for COI and COII (n = 2): T(57), C(144), T(156), G(465), G(504), C(798), G(1548).

Description

Holotype male: Total length 3.17; leg I femur 2.81; F1/CL ratio 2.49. 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. 27B). Carapace tall (CH/CL ratio 2.00); 1.13 long, 2.26 high, 1.06 wide; ‘neck’ 0.54 wide; bearing two pairs of rudimentary horns; highest point of pars cephalica (HPC) near posterior third of ‘head’ (ratio of HPC to post-ocular length 0.63), carapace gently sloping posterior to HPC; ‘head’ moderately elevated postero-dorsally (post-ocular ratio 0.32) (Fig. 9H). Chelicerae with long brush of accessory setae on anterior face of paturon (Fig. 27C). Abdomen 1.64 long, 1.10 wide; with three pairs of dorsal hump-like tubercles (HT 1–6); dorsal scute fused anteriorly to epigastric sclerites, extending posteriorly to first pair of hump-like tubercles; HT 3–6 each covered by separate dorsal sclerites. Fully expanded pedipalp (Figs 27D-E) with conductor hinged to, and obscured by, embolic haematodocha; tegular sclerite 1 (TS 1) rod-like, bluntly-pointed, visible in retro-ventral view; TS 2 spur-like, slightly longer than TS 1, largely obscured by TS 3; TS 2a sinuous, filiform, exposed distally; TS 3 exposed, plate-like, overlying TS 2, with curved, triangular apex directed toward proximal conductor.
Allotype female: Total length 3.49; leg I femur 2.86; F1/CL ratio 2.28. Cephalothorax dark reddish-brown; legs tan-brown with darker annulations; abdomen mottled grey-brown and beige (Fig. 27A). Carapace tall (CH/CL ratio 2.04); 1.26 long, 2.56 high, 1.18 wide; ‘neck’ 0.64 wide; bearing two pairs of rudimentary horns; highest point of pars cephalica (HPC) near middle of ‘head’ (ratio of HPC to post-ocular length 0.60), carapace gently sloping posterior to HPC; ‘head’ moderately elevated dorsally (post-ocular ratio 0.33) (Fig. 7O). Chelicerae without accessory setae on anterior face of paturon. Abdomen 2.00 long, 1.41 wide; with three pairs of dorsal hump-like tubercles (HT 1–6). Internal genitalia with cluster of ≤ 12 variably shaped spermathecae on either side of gonopore, clusters meeting near midline of genital plate (Fig. 27F); innermost (anterior) spermathecae longest, sausage-shaped, curved antero-laterally; other spermathecae variably aciniform, straight, directed antero-laterally.
Variation: Females (n=2): total length 3.38–3.49; carapace length 1.26 (invariable); carapace height 2.56–2.62; CH/CL ratio 2.04–2.08.

Distribution and habitat

Austrarchaea mcguiganae is known only from mesic closed forest habitats in the Monga National Park of southern New South Wales (Fig. 45). A female specimen from Deua National Park may also belong to this species based on proximity, and numerous juvenile specimens from the Badja State Forest possess divergent mtDNA sequences indicative of possible speciation (Fig. 3B).

Conservation status

This species appears to be a short-range endemic taxon (Harvey 2002b^[1]), which although potentially restricted in distribution, is abundant within the Monga National Park near Link Road (M. Rix, pers. obs.). It is not considered to be of conservation concern.

Original Description

• Rix, M; Harvey, M; 2011: Australian Assassins, Part I: A review of the Assassin Spiders (Araneae, Archaeidae) of mid-eastern Australia ZooKeys, 123: 1-100. doi

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

Images

Figure 1. Habitus images of live Archaeidae from mid-eastern Australia: A–B, female Austrarchaea nodosa (Forster, 1956) from Binna Burra, Lamington National Park, Queensland; C–D, female A. mascordi sp. n. from Coolah Tops National Park, New South Wales; E–F, juvenile A. raveni sp. n. from Mount Glorious, Queensland. Images A–D by M. Rix; images E–F by Greg Anderson, used with permission.  Figure 3. Molecular phylogenetic data analysed as part of this study. A, Schematic map of the mitochondrial cytochrome c oxidase subunit I–II (COI–COII) gene complex in Archaeidae and other basal Araneomorphae, showing (i) the position of primers used to amplify and sequence 1.6 kilobases of mtDNA, and (ii) the inferred stop and initiation codons for COI and COII, respectively. Note the centralised, overlapping position of the two internal sequencing primer sites (SeqF2a/SeqR1), and the TTG initiation codon for COII, present in all but one of the spider species sequenced for this study. B, Majority-rule consensus tree with re-estimated branch lengths, resulting from a combined, gene-partitioned Bayesian analysis of the COI–COII mtDNA data. Thickened branches represent clades with >95% posterior probability support, and individual support values are shown above other nodes.  Figure 7. Lateral ‘head’ profiles of females of species of Austrarchaea from mid-eastern Australia, 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): A, allotype A. alani sp. n.; B, allotype A. aleenae sp. n.; C, allotype A. judyae sp. n.; D, allotype A. raveni sp. n.; E, allotype A. harmsi sp. n.; F, allotype A. monteithi sp. n.; G, allotype A. cunninghami sp. n.; H, allotype A. dianneae sp. n.; I, A. nodosa (Forster, 1956); J, allotype A. platnickorum sp. n.; K, allotype A. binfordae sp. n.; L, A. milledgei sp. n. (WAM T112568); M, allotype A. mascordi sp. n.; N, allotype A. smithae sp. n.; O, allotype A. mcguiganae sp. n. Asterisks (*) denote concave depressions.  Figure 9. Lateral ‘head’ profiles of males of species of Austrarchaea from New South Wales (excluding the Border Ranges), 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): A, holotype A. monteithi sp. n.; B, holotype A. christopheri sp. n.; C, holotype A. platnickorum sp. n.; D, holotype A. binfordae sp. n.; E, holotype A. milledgei sp. n.; F, holotype A. mascordi sp. n.; G, holotype A. smithae sp. n.; H, holotype A. mcguiganae sp. n.; I, holotype A. helenae sp. n. Asterisks (*) denote concave depressions.  Figure 27. Austrarchaea mcguiganae sp. n. A–B, Cephalothorax and abdomen, lateral view: A, allotype female (AMS KS114975) from Monga National Park, New South Wales; B, holotype male (AMS KS62790) from Monga National Park, New South Wales. C, Holotype male chelicerae, lateral view, showing accessory setae. D–E, Holotype male pedipalpal bulb (fully expanded), retro-ventral view. G, Allotype female internal genitalia, dorsal view. bH = basal haematodocha; C = conductor; Cy = cymbium; E = embolus; eH = embolic portion of distal haematodocha; Es = embolic sclerite; pH = proximal portion of distal haematodocha; T = tegulum; (TS)1–3 = tegular sclerites 1–3. Scale bars: A–B = 1.0 mm; E = 0.2 mm.  Figure 45. Austrarchaea mcguiganae sp. n., distribution and habitat: A, topographic map showing the known distribution of Archaeidae in south-eastern Queensland and eastern New South Wales, with collection localities for A. mcguiganae highlighted in yellow (red highlighted localities denote specimens of tentative identification; orange highlighted localities denote genotyped juvenile specimens of tentative identification); B, satellite image showing detail of inset (A); C, wet eucalypt forest at the type locality – Link Road, Monga National Park, New South Wales (April 2010). Image (C) by M. Rix.