Difference between revisions of "Austrarchaea mascordi"

Latest revision as of 15:59, 15 August 2011

Taxonavigation

Ordo: Araneae
Familia: Archaeidae
Genus: Austrarchaea

Name

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

Type material

Holotype male: Coolah Tops National Park, off Gemini Road Loop, New South Wales, Australia, 31°48'59"S, 150°10'31"E, sifting elevated leaf litter under tree ferns, open eucalypt forest with ferny understory, 1159 m, 12-13.IV.2010, M. Rix, D. Harms (AMS KS114972).
Paratypes: Allotype female, same data as holotype (AMS KS114974); 1 female, same data as holotype (AMS KS114973DNA: Ar41-48-F); 3 females and 6 juveniles, same data as holotype (WAM T112566DNA: Ar41-113-J/Ar41-114-J).

Other material examined

AUSTRALIA: New South Wales: Coolah Tops National Park: Breeza Lookout, 31°49'08"S, 150°11'38"E, sifting elevated leaf litter under bracken ferns, open eucalypt forest with ferny understory, 1128 m, 12-13.IV.2010, M. Rix, D. Harms, 1♂ (WAM T112565DNA: Ar40-115-M); Breeza Lookout, 31°49'17"S, 150°11'28"E, pitfall trap, 7-25.XI.2001, M. Gray, G. Milledge, H. Smith, 1♂ (AMS KS75412).

Etymology

The specific epithet is a patronym in honour of the late Ramon Mascord (1913–1983), for his pioneering contributions to arachnology and natural history, and for writing two of the most influential popular books on Australian spiders (see Mascord 1970^[1], 1980).

Diagnosis

Austrarchaea mascordi can be distinguished from all other Archaeidae from mid-eastern Australia by the relatively short, filiform tegular sclerite 1 (TS 1) (Fig. 24F) combined with the unique shape of the conductor (Figs 24D-E), which is thin and slightly twisted, with a sharply-tapered apex.
This species can also be distinguished from other genotyped taxa from mid-eastern Australia (see Fig. 3B) by the following six unique nucleotide substitutions for COI and COII (n = 4): C(348), G(468), C(651), C(957), A(967), G(1364).

Description

Holotype male: Total length 2.83; leg I femur 2.67; F1/CL ratio 2.45. 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. 24B). Carapace tall (CH/CL ratio 2.14); 1.09 long, 2.33 high, 1.02 wide; ‘neck’ 0.54 wide; bearing two pairs of rudimentary horns; highest point of pars cephalica (HPC) approaching posterior third of ‘head’ (ratio of HPC to post-ocular length 0.62), carapace gently sloping posterior to HPC; ‘head’ not strongly elevated dorsally (post-ocular ratio 0.28) (Fig. 9F). Chelicerae with brush of accessory setae on anterior face of paturon (Fig. 24C). Abdomen 1.44 long, 1.08 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. Unexpanded pedipalp (Figs 24D-F) with thin, sharply-tapered, slightly twisted conductor; tegular sclerite 1 (TS 1) filiform, obscured by conductor in retrolateral view; TS 2 spur-like, longer than TS 1; TS 2a sinuous, filiform, exposed distally; TS 3 embedded proximally within distal haematodocha, with arched dorsal margin and sharply-pointed apex projecting ventrally beyond retro-distal rim of tegulum.
Allotype female: Total length 3.28; leg I femur 2.87; F1/CL ratio 2.29. Cephalothorax dark reddish-brown; legs tan-brown with darker annulations; abdomen mottled grey-brown and beige (Fig. 24A). Carapace tall (CH/CL ratio 2.11); 1.26 long, 2.65 high, 1.13 wide; ‘neck’ 0.62 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’ not strongly elevated dorsally (post-ocular ratio 0.26) (Fig. 7M). Chelicerae without accessory setae on anterior face of paturon. Abdomen 1.90 long, 1.54 wide; with three pairs of dorsal hump-like tubercles (HT 1–6). Internal genitalia with cluster of ≤ 10 variably shaped spermathecae on either side of gonopore, clusters meeting near midline of genital plate (Fig. 21G); innermost (anterior) spermathecae longest, bilobed, curved antero-laterally; other spermathecae variably pyriform, mostly straight, directed antero-laterally.
Variation: Males (n=3): total length 2.83–2.92; carapace length 1.09–1.10; carapace height 2.33–2.37; CH/CL ratio 2.14–2.17. Females (n=5): total length 2.97–3.49; carapace length 1.21–1.26; carapace height 2.49–2.65; CH/CL ratio 2.05–2.11.

Distribution and habitat

Austrarchaea mascordi is known only from snow gum and wet eucalypt forest habitats in the Coolah Tops National Park, west of Scone, New South Wales (Fig. 42).

Conservation status

This species is a short-range endemic taxon (Harvey 2002b^[2]), which although restricted in distribution, is abundant within the eastern Coolah Tops National Park (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. ↑ Mascord R (1970) Australian Spiders in Colour. Reed Books, Sydney, 112 pp.
2. ↑ 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 21. Austrarchaea platnickorum sp. n. A–B, Cephalothorax and abdomen, lateral view: A, allotype female (AMS KS114970) from New England National Park, New South Wales; B, holotype male (AMS KS114971) from New England National Park, New South Wales. C, Holotype male chelicerae, lateral view, showing accessory setae. D–F, Holotype male pedipalp: D–E, bulb, retrolateral view; F, detail of distal tegular sclerites, prodistal view. G, Allotype female internal genitalia, dorsal view. Note the broken left tegular sclerite 1 (TS 1) in (F), highlighted (*) at the point of breakage, compared to the long, sharply-pointed right TS 1 (see inset). C = conductor; E = embolus; Es = embolic sclerite; T = tegulum; (TS)1–3 = tegular sclerites 1–3. Scale bars: A–B = 1.0 mm; E = 0.2 mm.  Figure 24. Austrarchaea mascordi sp. n. A–B, Cephalothorax and abdomen, lateral view: A, allotype female (AMS KS114974) from Coolah Tops National Park, New South Wales; B, holotype male (AMS KS114972) from Coolah Tops National Park, New South Wales. C, Holotype male chelicerae, lateral view, showing accessory setae. D–F, Holotype male pedipalp: D–E, bulb, retrolateral view; F, detail of distal tegular sclerites, prodistal view. G, Allotype female internal genitalia, dorsal view. C = conductor; E = embolus; Es = embolic sclerite; T = tegulum; (TS)1–3 = tegular sclerites 1–3. Scale bars: A–B = 1.0 mm; E = 0.2 mm.  Figure 42. Austrarchaea mascordi 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. mascordi highlighted in yellow; B, satellite image showing detail of inset (A); C, open eucalypt forest near the type locality – Breeza Lookout, Coolah Tops National Park, New South Wales (April 2010). Image (C) by M. Rix.