NANOMETINAE FORSTER AND FORSTER, 1999

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

SUBFAMILY NANOMETINAE FORSTER AND FORSTER, 1999

Nanometidae Forster and Forster, 1999: 166. Nanometinae Álvarez-Padilla and Hormiga,

2011: 802.

TYPE GENUS: Nanometa Simon, 1908 .

DIAGNOSIS: Male nanometines are diagnosed from other tetragnathids by their cymbial ectobasal process shaped as relatively large spine attached to the cymbium (e.g., figs. 7B, 8C, 10E, 23E). This process is smaller in Taraire (figs. 46D, 48E, F, 49C, 50C) and Chrysometa ( Salgueiro-Sepúlveda and Álvarez-Padilla, 2018: 308, fig. 4A–C), long and flattened in Tawhai (figs. 52D, 54A–C), and bearing small teeth in Allende Álvarez-Padilla, 2007 ( Álvarez-Padilla, 2007: 295, fig. 5C). The conductor originates from the center of the tegulum; it is shaped either as a flat disk in Nanometa (figs. 10C, F, 13C) or projects apically in Pinkfloydia ( Dimitrov and Hormiga, 2011: 759, fig. 14A). Although the branched median tracheae (figs. 11D, 30D) and the booklung-coxae stridulatory apparatus (figs. 20F, 30C) are found in most nanometines, these two features are absent in Pinkfloydia . Female nanometines present two types of genital anatomy. One is found in Pinkfloydia , with a protruding epigynal plate (relative to Nanometa ) bearing numerous pores opening on its ventral surface ( Dimitrov and Hormiga, 2011: 761, fig. 15G) (similar to those of Tawhai ), soft-walled spermathecae, and copulatory and fertilization ducts short, parallel, and well sclerotized ( Dimitrov and Hormiga, 2011: 761, figs. 15F–H). The other is a flat epigynal plate, without conspicuous pores and four receptacles, two of which are the spermathecae shared by all Nanometa as well as Taraire (figs. 9H, 11C, 13E, 47F, 48C, 50E).

RELATIONSHIPS: Putative morphological synapomorphies of Nanometinae include the conductor originating from the center of the tegulum, a flexible conductor-tegulum attachment, tubular embolus, a basal ecto-basal process shaped as relatively large spine; absence of macrosetae on the male palpal patella; presence of cheliceral denticles, and epigynal mating plug from secretions ( Álvarez-Padilla and Hormiga, 2011; Dimitrov and Hormiga, 2011).

COMPOSITION: Two genera, Nanometa and Pinkfloydia . In favor of taxonomic stability, Taraire , Tawhai , Chrysometa , Allende and Metleucauge remain outside Nanometinae , because the nodes involving their placement lack strong consistent support (figs. 61–63).

DISTRIBUTION: Nanometines are distributed in New Zealand, Australia, New Caledonia, and Papua New Guinea.