Family Microstigmatidae Roewer, 1942

Type genus

Microstigmata Strand, 1932 by original designation.

Composition

Angka Raven & Schwendinger, 1995, Envia Ott & Höfer, 2004, Ixamatus Simon, 1887, Kiama Main & Mascord, 1969, Micromygale Platnick & Forster, 1982, Microstigmata Strand, 1932, Ministigmata Raven & Platnick, 1981, Pseudonemesia Caporiacco, 1955, Spelocteniza Gertsch, 1982, Tonton Passanha, Cizauskas & Brescovit, 2019, Xamiatus Raven, 1981 .

Diagnosis

Distinguished from other genera of Nemesoidina (sensu Montes de Oca et al. 2022) by the following combination of characters: tarsi not flexible (Figs 2D, 22C); inferior tarsal claw present; intercheliceral tumescence inconspicuous (Fig. 7C); pustulose or scaly cuticule present (Fig. 25C–D). Furthermore members of the subfamily Microstigmatinae can be further delineated as follows: tribe Microstigmatini are distinguished by their superior tarsal claw biseriate; pustulose leg cuticle (Fig. 25C–D); highly elevated, smooth tarsal organ (visible under SEM) (Figs 25A, 28F, 29E) and smooth trichobothrial base (Fig. 28C); cymbium without spines (Figs 8A, 17A); those of the tribe Pseudonemesiini are distinguished by their superior tarsal claw biseriate; scaly cuticle on leg (Indicatti & Villarreal 2016: fig. 3c); low tarsal organ with concentric rings, not observed for Envia (Indicatti & Villarreal 2016: fig. 5a); corrugated trichobothrial base (Indicatti & Villarreal 2016: fig. 5c–d); cymbium with spines (Fig. 3A).

Members of the subfamily Micromygalinae are diagnosed by the combination of the following characters: superior tarsal claw uniserate; low tarsal organ with concentric rings (Platnick & Forster 1982: fig. 7; Passanha et al. 2019: fig. 1e); scaly cuticule (Platnick & Forster 1982: fig. 8); trichobothria absent on tarsi but present on metatarsi (in Micromygale, Platnick & Forster 1982: fig. 9) and present with corrugated bases on tarsi (in Tonton, Passanha et al. 2019: fig. 1c).

Description

Tiny to medium-sized mygalomorph spiders (0.75–31.00); 0, 2, or 8 eyes in quadrangle; cephalothorax elongated, oval, fovea variable; anterior lobe of maxillae not well-developed; spinnerets short (only two in Ministigmata, with two vestigial in Pseudonemesia); legs with pustulose or scaly cuticle; leg tarsi with three claws; tarsi and / or metatarsi with filiform trichobothria; tarsal organ elevated and smooth or low with concentric ridges.

Distribution

Australia, Central and South America, South Africa and Thailand.