Tricellina gertschi ( Forster & Platnick, 1981 )

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: 35-36

publication ID

http://doi.org/ 10.3897/zookeys.36.306

publication LSID

lsid:zoobank.org:pub:ADCACC88-6C78-4386-8E33-3F98234ECE92

DOI

http://doi.org/10.5281/zenodo.3789389

persistent identifier

http://treatment.plazi.org/id/7E13878E-FF94-1B5F-FF32-1D27FEFD8DE1

treatment provided by

Plazi

scientific name

Tricellina gertschi ( Forster & Platnick, 1981 )
status

 

Tricellina gertschi ( Forster & Platnick, 1981)  

Figs 7D View Figure 7 , 23 View Figure 23 G–H, 33D, 40–45, 212

Tricella gertschi Forster & Platnick, 1981: 266   , figs 1–2, 4–10, 14–15, 20–22 (holotype male from west of Cherquenco, Cautín province, Chile, in AMNH, not examined). Brignoli, 1983: 696.

Tricellina gertschi (Forster & Platnick)   : Forster & Platnick, 1989 in Platnick, 1989: 166. Platnick et al., 1991: 5, figs 240–244. Platnick, 2009.

Material examined. CHILE: Región IX (de la Araucanía): Cautín: 4 km W. of Cherquenco, near Temuco , 28.IV.1961, L. Smith, 1♁, 6♀ ( AMNH). Malleco: Monumento Natural Contulmo, 31.I.1986, N. Platnick, T. Schuh, 1♀ ( AMNH)   ; same data except 23.I.1985, N. Platnick, O. Francke, 1♀ ( AMNH). Región X (Los Lagos): Chiloé: Chiloé Island , 5 km N. of Quellon, 1.XII.1981, N. Platnick, T. Schuh, 1♁ ( AMNH)   ; same data, 1♁, 5♀ ( AMNH). Llanquihue: 35 km NW. of Río Negro, 24.I.1986, N. Platnick, T. Schuh, 3♀ ( AMNH). Osorno : Termas de Puyehue , 25.XI.1981, N. Platnick, T. Schuh, 1♀ ( AMNH)   ; same data except 24.XI.1981, 6♁, 15♀ ( AMNH)   ; Volcán Osorno, 12.II.1985, N. Platnick, O. Francke, 1♀ ( AMNH). Palena: 25–27 km N. of Chaitén , 17.I.1986, N. Platnick, P. Goloboff, T. Schuh, 2♁, 6♀ ( AMNH)   ; 70 km S. of Chaitén , 16.I.1986, N. Platnick, P. Goloboff, T. Schuh, 5♁, 35♀ ( AMNH)   ; vicinity of Chaitén , 5–7.XII.1981, N. Platnick, T. Schuh, 1♀ ( AMNH)   ; same data except 7.XII.1981, 12♁, 29♀ (AM- NHSEM♁ ♀)   .

Remarks. Tricellina gertschi   is the only species in the tribe Micropholcommatini   known to occur in Chile, where it is relatively widespread (Fig. 212). Forster and Platnick (1981) discussed the similarities of T. gertschi   to a number of Australasian micropholcommatid taxa, suggesting a possible close relationship to Raveniella hickmani   , R. luteola   and Guiniella tropica   (then all placed in Textricella   ). The original naming of ‘ Tricella   ’ (a contraction of ‘ Textricella   ’) and the associated discussion on relationships were based on the assumption that T. gertschi   was closely related to Textricella parva Hickman   (= Eterosonycha alpina Butler   ) and other taxa now in the Textricellini   ; an erroneous interpretation based largely on a homoplastic morphology of the abdominal respiratory system. Tricellina gertschi   was also described by Forster and Platnick (1981: 266) as a likely haplogyne spider, with “paired spherical receptacula, of which one is membranous”; an interpretation which resulted in the inclusion of T. gertschi   in a cladistic analysis of haplogyne taxa by Platnick et al. (1991). The second “membranous” receptaculum identified by Forster and Platnick (1981) is actually a distal series of coiled, membranous insemination ducts surrounding a central, posteriorly-directed fertilisation duct – a morphology shared with species of Austropholcomma   ( Fig. 33 View Figure 33 ). Tricellina   is now known to be a typical, entelegyne micropholcommatine taxon, closely related to Austropholcomma   from Australia.

Tribe Textricellini Hickman, 1945   , new rank

Textricellidae   Hickman, 1945: 136. Type genus Textricella Hickman, 1945   (= Eterosonycha Butler, 1932   ).

Diagnosis. Species of Textricellini   can be distinguished from all other Micropholcommatidae   by the presence of a modified, enlarged and sinuous flagelliform gland spigot on the posterior lateral spinnerets (the ‘textricellin FL gland spigot’) ( Fig. 46 View Figure 46 ), usually visible only with a scanning electron microscope. With the exception of the basal species Tinytrella pusilla ( Forster, 1959)   , species of Textricellini   can also be distinguished from all other Micropholcommatidae   by the presence of two or three peg teeth on the male cheliceral promargin ( Figs 47 View Figure 47 A–B), and the presence of ornate, ridged cuticular sculpturing on the male pedipalpal patella ( Figs 47 View Figure 47 C–D). The tribe can be further distinguished from all other Micropholcommatinae   by the absence in all but a few taxa of a dorsal scute on both the male and female abdomen ( Figs 76 View Figure 76 A–B). The ‘textricellin somatic gestalt’ (see Remarks, below) is also extremely distinctive and useful for identification.

Distribution. South-eastern and south-western mainland Australia, Tasmania, Lord Howe Island, Papua New Guinea, New Zealand and southern Chile. This distribution is largely congruent with a vicariant, Gondwanan biogeography (Fig. 217) (see Biogeography, below).

Included genera. Eterosonycha Butler   ( Fig. 7E View Figure 7 ) and the nine new genera Algidiella   ( Fig. 7K View Figure 7 ), Eperiella   ( Fig. 7J View Figure 7 ), Epigastrina   ( Fig. 7F View Figure 7 ), Guiniella   ( Fig. 72 View Figure 72 ), Normplatnicka   ( Fig. 7I View Figure 7 ), Raveniella   ( Fig. 7G View Figure 7 ), Rayforstia   ( Fig. 7H View Figure 7 ), Taliniella   ( Fig. 7L View Figure 7 ) and Tinytrella   ( Fig. 7M View Figure 7 ).

Remarks. While difficult to quantify empirically, species of Textricellini   possess an extremely distinctive overall somatic morphology, or ‘gestalt’, unique among Micropholcommatidae   (see Figs 7 View Figure 7 E–M). This textricellin somatic gestalt was recognised in the traditional generic concept of ‘ Textricella   ’ (see Forster 1959) and the old family concept of Textricellidae   ( Platnick and Forster 1986), and is often so obvious that an experienced arachnologist can identify a spider as a textricellin without the use of a microscope.

AMNH

American Museum of Natural History

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Micropholcommatidae

Genus

Tricellina

Loc

Tricellina gertschi ( Forster & Platnick, 1981 )

Rix, Michael & Harvey, Mark 2010
2010
Loc

Tricellina gertschi (Forster & Platnick)

Platnick NI & Coddington JA & Forster RR & Griswold CE 1991: 5
1991
Loc

Tricella gertschi

Brignoli PM 1983: 696
Forster RR & Platnick NI 1981: 266
1981
Loc

Textricellidae

Hickman VV 1945: 136
1945