Nanometa dutrorum, Álvarez-Padilla & Kallal & Hormiga, 2020

Álvarez-Padilla, Fernando, Kallal, Robert J. & Hormiga, Gustavo, 2020, Taxonomy And Phylogenetics Of Nanometinae And Other Australasian Orb-Weaving Spiders (Araneae: Tetragnathidae), Bulletin of the American Museum of Natural History 2020 (438), pp. 1-107 : 1-107

Nanometa dutrorum , sp. nov.

Figures 31, 33, 36–37

TYPE MATERIAL: Male holotype and female allotype from Australia, Tasmania, Weldborough Pass Scenic Reserve, 28.6 km 280° WNW St Helens, 41° 12′ 59.8″ S, 147° 56′ 18.2″ E, 480 m. G. Hormiga, L. Lopardo. 6–7 March 2006. Nothofagus forest (male specimen also DNA voucher GH0128), both types deposited at the Tasmanian Museum and Art Gallery (Hobart).

DIAGNOSIS: Males of N. dutrorum can be differentiated from the other small Nanometa species by having the CEMP bearing a conspicuous apophysis (figs. 31C, 33C), and the CEBP having only two small apophyses and a square cymbial outgrowth (figs. 31A, 33A). The conductor tip is covered with several sclerotized denticles (figs. 31A, E, G, 33A–C) and the embolus is marginally serrated. Females of N. dutrorum can be separated from other small Nanometa species by having oval and shallow genital openings approximately 1/2 of the epigynum width, located at the center of the epigynal plate (figs. 33D, 36D). Genital opening rebordered by thick cuticular margin, septum discontinuous near the genital openings’ posterior margin (fig. 36D).

DESCRIPTION: Female (GH0128) total length 4.1. Cephalothorax length 1.4, width 1.2. Clypeus height 1.0 AME diameter. Cephalothorax background pale-yellow, with light-gray coloration concentrated over the ocular area and the carapace lateral edges. Endites and sternum color dark gray. Cheliceral promargin and retromargin each with three and two teeth, with ca. three cheliceral denticles. Abdomen dorsum background light gray, silvery guanine patches covering all abdomen dorsal surface, except the central line that extends all the abdomen length, lateral surface covered with guanine patches over dorsal half, ventral half with brown pattern, ventral surface brown intercalated with silvery guanine patches and with a central rectangle flanked by two lines. Booklung stridulatory organ absent. Tracheae and epigynum not observed with SEM. Femur I length 2.4. Copulatory openings small, shallow, ovate, forming Y-shaped pattern between them and cuticular margin. Copulatory duct enlarged, similar in size to spermathecae.

Male (GH0128) same as female except as noted. Total length 3.4. Cephalothorax length 1.5 width 1.3. Clypeus 1.1 AME diameter. Cephalothorax and abdomen coloration slightly darker than in female, silvery guanine patches less conspicuous. Cheliceral promargin and retromargin with three and two teeth respectively, with ca. three cheliceral denticles. Stridulatory organ formed by a cuticular ridge on the booklung anterior edge, coxa IV retrolateral surface not observed with SEM. Femur I length 3.0. Pedipalp with two-pronged CEBP (figs. 31A, 33A–C), paracymbium small (figs. 31A, 33A), CEMP with long apophysis (fig. 33B), conductor denticulated and embolus with marginal serration (figs. 31A, E, 33A–C).

VARIATION: Females (N = 2) total length 3.9– 4.1, cephalothorax length 1.3–1.4, width 1.0–1.1.

ETYMOLOGY: The species epithet is a patronym in honor of paleontologist John Thomas Dutro (1923–2010) and his wife Nancy P. Dutro, for their boundless generosity to G.H.

DISTRIBUTION: This species is found in Tasmania and Victoria (fig. 37D).

MATERIAL EXAMINED: N = 3. AUSTRALIA, Tasmania, St. Columbia Falls, 27.1km 256° W St Helens, 41° 19′ 17.2″ S, 147° 55′ 33.7″ E, 335 m, G. Hormiga & L. Lopardo, 7 March 2006, Eucalyptus / Casuarina woodland, 1 male, GWU. Victoria, Mt. St. Leonard, 37° 34′ S, 145° 32′ E, 6 April 1991, M.S. Harvey, M.E. Blosfelds, NMV.