Pua Forster, 1959

Rix, Michael & Harvey, Mark, 2010, The spider family Micropholcommatidae (Arachnida: Araneae: Araneoidea): a relimitation and revision at the generic level, ZooKeys 36 (36), pp. 1-321 : 28-29

Genus Pua Forster, 1959

Pua Forster, 1959: 299 . Type species by original designation Pua novaezealandiae Forster, 1959 . Brignoli, 1983: 374. Platnick, 2009.

Affinities. The genus Pua appears to be the sister-lineage to Micropholcomma from Australia ( Fig. 4 ).

Diagnosis. Pua novaezealandiae can be distinguished from all other Micropholcommatini by the presence of a short (length <5× width), hooked embolus situated distally on a rotated bulb ( Figs 29 A–C). Other diagnostic characters include the loss of the AME ( Fig. 25B ), the presence of very large, globular spermathecae (Fig. 15F), and the presence of a dorsal scute on the female abdomen ( Fig. 24B ).

Description. Very small, entelegyne Araneoidea ; total length 0.80 to 1.00. Cephalothorax: Carapace without glandular depressions above maxillae ( Fig. 26D ); cuticle without glandular pits ( Fig. 26E ); margins fused to sternum via pleural sclerites. Six eyes present on anterior margin of pars cephalica ( Fig. 25B ); AME absent. Chelicerae without bulging anterior projections in males; promargin with true teeth, a pair of fused setal sockets adjacent to base of fang and single peg tooth in males ( Fig. 27F ).

Legs and female pedipalp: Legs three-clawed ( Fig. 28D ), covered with smooth or serrate hair-like setae. Trichobothria present on legs; tibiae each with two (legs I–III) or three (leg IV) trichobothria ( Fig. 28C ); metatarsi without trichobothria. Female pedipalp four-segmented, with fused tibia-tarsus; claw absent ( Figs 27 C–D).

Abdomen: Abdomen oval-globose; anterior sclerite present around epigastric region and petiole; large dorsal scute present on males and females ( Figs 24 A–B); lateral sclerotic strips present on males; posterior sclerotic ring surrounding spinnerets and colulus. Six spinnerets situated posterior to fleshy colulus ( Figs 23 C–D); PMS without AC gland spigots; PLS with complete triad. Anterior tracheal system well-developed, with relatively large lateral atria and multiple radiating tracheae; second tracheal tubes on each side looping mesally and extending through petiole into cephalothorax; posterior tracheal spiracle absent.

Genitalia: Male pedipalp ( Fig. 29 ) relatively simple; patella with distally-directed, hooked ligulate retrolateral apophysis; bulb rotated 180 degrees, with embolus inserting distally relative to cymbium; tegulum smooth, with straight, evaginated tegular ridge; embolus exposed, short (length <5× width) and hooked; conductor absent. Female genitalia (Fig. 15F) with pair of separate, very large, globular anterior spermathecae; insemination ducts short, barely visible in dorsal view; fertilisation ducts simple, curved.

Distribution. New Zealand.

Composition. Only the type species Pua novaezealandiae Forster, 1959 .

Figures

Figure 4. Optimal cladogram for the Micropholcommatidae under equal and implied weights, and one of six equally parsimonious trees recovered from an equal weights analysis of the ‘new’ matrix (length = 135; see Appendix II). With the exception of the highlighted (*) node ‘Patelliella adusta + Micropholcommatini’, all clades shown were recovered in all iterations of an implied weights analysis (K=1–6); the phylogenetic position of P. adusta changed to ‘P. adusta + Textricellini’ under K-values 1–5. Unambiguous character optimisations are shown for each node, and bold species are newly described, with generic type species highlighted (*).

Figure 23. Scanning electron micrographs of posterior median spinnerets of female (left) and male (right) Micropholcommatini: A–B Micropholcomma bryophilum (Butler) from near Marysville, Victoria (WAM T94453) C–D Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH) E–F Austropholcomma florentine sp. n. from the Florentine Valley, Tasmania (FMC) G–H Tricellina gertschi (Forster & Platnick) from near Chaitén, Chile (AMNH). Note the apparent loss of the anterior CY gland spigot in female Austropholcomma and Tricellina. Arrows denote the anterior, mesal direction.

Figure 24. Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH): A male habitus, dorsal view B female habitus, dorsal view C male abdomen, ventral view D female abdomen, ventral view.

Figure 25. Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH): A male habitus, antero-lateral view B female cephalothorax, frontal view.

Figure 26. Scanning electron micrographs of Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH): A female eyes and clypeus, frontal view B male sternum, ventro-lateral view C male abdominal cuticle D male corner of carapace above left maxilla E female pars thoracica, lateral view, showing setal tubercles F female chelicerae and labrum.

Figure 27. Scanning electron micrographs of Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH): A female chelicera, frontal view B female cheliceral promargin C female pedipalp, frontal view D tip of female pedipalp, showing fused tibia-tarsus E male chelicera, antero-lateral view F male cheliceral promargin.

Figure 28. Scanning electron micrographs of female Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH): A leg I tarsal organ B leg I lyriform organ C leg I tibial trichobothrium D leg IV claws, showing elongate inferior claw.

Figure 29. Scanning electron micrographs of pedipalp of male Pua novaezealandiae Forster from the Makarora Valley, New Zealand (AMNH).