Tinytrella pusilla ( Forster, 1959 ), 2010

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 : 75

Tinytrella pusilla ( Forster, 1959) , comb. n.

Figs 7M , 8A, 8C, 8E , 9B , 10C, 126B, 126D, 126F, 136–137, 138A–B, 139–142

Textricella pusilla Forster, 1959: 294 , figs 51–57, 140 (holotype male from east of Dog Hill, Canterbury, New Zealand, in Canterbury Museum, not examined). Brignoli, 1983: 375. Platnick, 2009.

Selected material examined. NEW ZEALAND: South Island: Canterbury: creek E. of Dog Hill, tributary of the Hurunui River , 12.V.1952, J. Dugdale, 1♁, 2♀ ( AMNH) ; Mt Richardson , 31.III.2006, M. Rix. 1♁ ( WAM T94458) . Southland: Alton Burn, Tuatapere , 13.III.1981, R. Forster, 6♁, 8♀ ( AMNH) ; Fiordland National Park, S. end of Lake Te Anau , 21.IV.1995, C. Griswold, T. Meikle, 1♁, 2♀ ( CAS) ; Lake Hauroko , 25.II.1970, R. Forster, C. Wilton, 2♁, 5♀ ( AMNH) ; Lake Monowai , 15.I.1971, R. Forster, 4♁, 3♀ ( AMNH) ; N. of Te Anau , 19.II.1965, N. Walker, 12♁, 37♀ (AMNHSEM♁ ♀) . North Island: Wellington: Orongorongo , 18.IX.1969, J. Watt, 17♁, 12♀ ( AMNH) .

Remarks. Tinytrella pusilla is a small, brown species from the North and South Islands of New Zealand, recognised by Forster (1959) as different to all other Textricellini in New Zealand. It appears to be the most basal textricellin taxon known, sister to all other described species ( Fig. 4 ). Nothing is known of its biology or habits.

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 7. The genera of Micropholcommatidae, illustrated with habitus photographs of representative male specimens. A–D tribe Micropholcommatini: A Micropholcomma caeligenum Crosby & Bishop B Pua novaezealandiae Forster C Austropholcomma florentine sp. n. D Tricellina gertschi (Forster & Platnick). E–M tribe Textricellini: E Eterosonycha aquilina sp. n. F Epigastrina fulva (Hickman) G Raveniella peckorum sp. n. H Rayforstia vulgaris (Forster) I Normplatnicka lamingtonensis (Forster)] Eperiella alsophila sp. n. K Algidiella aucklandica (Forster) L Taliniella nigra (Forster) M Tinytrella pusilla (Forster). N Patelliella adusta sp. n., tribe Patelliellini. O–P subfamily Taphiassinae: O Olgania excavata Hickman P Taphiassa robertsi sp. n. Q–R subfamily Gigiellinae: Q Gigiella milledgei sp. n. R Gigiella platnicki sp. n. Note that Guiniella tropica (Forster) is not illustrated.

Figure 8. Diagnostic characters of the family Micropholcommatidae, illustrated with scanning electron micrographs: A–B evaginated tegular ridge and otherwise smooth tegulum of male Tinytrella pusilla (Forster) (left) and male Taphiassa robertsi sp. n. (right) C–D absence of the posterior minor ampullate gland spigot nubbin and tartipore on the posterior median spinnerets of female T. pusilla (left) and female T. robertsi (right) E–F ligulate retrolateral patellar apophysis of male T. pusilla (left) and male T. robertsi (right) G–H single anterior seta on the posterior median spinnerets of male Normplatnicka lamingtonensis (Forster) (left) and female T. robertsi (right).

Figure 9. Left pedipalps of male Micropholcommatini, Textricellini and Taphiassinae, showing trajectory of the sperm ducts: A Micropholcomma caeligenum Crosby & Bishop B Tinytrella pusilla (Forster) C Taphiassa punctata (Forster). Scale bars = 0.065 mm (65 µm). Numbered arrows denote the trajectory of the ducts, from the subtegular fundibule (1) to the base of the embolus.