Sathytes Westwood, 1870

Yin, Zi-Wei, Li, Li-Zhen & Zhao, Mei-Jun, 2012, Taxonomic study on Sathytes Westwood (Coleoptera: Staphylinidae: Pselaphinae) from China. Part I, Journal of Natural History 46 (13 - 14), pp. 831-857 : 833-835

Genus Sathytes Westwood

Sathytes Westwood, 1870: 128 . Type species: Sathytes punctiger Westwood, 1870 (by monotypy).

= Batoxylina Jeannel, 1957: 8–9 . Type species: Batoxylina clavalis Jeannel, 1957 , by original designation. (syn. in Löbl 1979: 285).

Diagnosis

Small to large in size. Surface roughly punctate. Antennal clubs formed by apical three antennomeres in the male, decorated with modifications varying in form; antennomeres IX bearing a semi-membranous apophysis or a truncate protuberance laterally (simple in S. simplex ). Elytra each with four basal foveae (three in S. minutus ). Tergite IV longest, VII with a pair of tiny lateral tubercles. Aedeagus simple in structure.

Description

Length 1.3–3.6. Head rectangular, slightly transverse to longitudinal. Lacking frontal rostrum. Clypeus hardly visible dorsally, arcuate anteriorly. Frons slightly depressed medially. Antennal tubercles indistinct. Vertex slightly convex, vertexal foveae welldefined to indistinct. Eyes prominent, medium to large-sized, their median line located at median to posterior half of head. Postocular margins shorter or longer than eyes. Gular area strongly depressed medially, with two small gular foveae; with lateral tubercles above depression. Antennae moderately elongate; scapes thick and large, pedicels longer than antennomeres III, III–VIII each wider than long, XI–XI strongly clubbed in male, weakly clubbed in female.

Pronotum as long as to slightly longer than wide; foveae and sulci greatly reduced, only lateral antebasal foveae present. Elytra wider than long in many species, usually with four basal foveae (three in S. minutus ), subhumeral foveae usually present (absent in S. punctiger ); with marginal stria; usually lacking sutural stria; discal stria absent. Thorax with lateral mesoventral foveae, median mesoventral foveae, lateral mesocoxal foveae and lateral metaventral foveae. Abdomen with tergite IV largest, two to six basal foveae present, lacking discal carinae; tergites V–VI each with two or six basal foveae. Sternite IV with eight basal foveae; sternites V–VI each with six basal foveae and VII with two. Aedeagus flat, median lobe broad; basal capsule rounded; parameres absent; with large basal foramen.

Male secondary sexual characters: antennal club formed by apical three antennomeres; antennomere IX with single semi-membranous apophysis mesally, XI with one or two basal protuberances which are truncate, blunt or rounded and decorated with special setae at apices; protibiae roundly expanded mesally at middle (only in S. tibialis ).

Remarks

A majority of the known species of Sathytes possess four basal elytral foveae, and six basal foveae each on tergites IV–VI. With a few exceptions, these foveae can be reduced. Sathytes minutus has three basal elytral foveae; S. vespertinus and S. reductus have four basal foveae on tergite IV and two each on tergites V–VI; two unnamed

species ( Löbl 1979) have two basal foveae each on tergites IV–VI. All Chinese Sathytes species described in this paper have an unreduced foveal pattern.