Mischotetrastichus

Mischotetrastichus Graham, 1987

Fore wing with submarginal vein (SMV) with a single dorsal seta dorsally. Postmarginal vein (PMV) rudimentary, distinctly shorter than stigmal vein (STV).
Antenna with 2 distinct anelli. Female funicle with 3 segments distinctly longer than wide. Male antenna with plaque on ventral side of scape and with funicle with 4 segments and with whorls of long setae. Club 3-segmented in both sexes.
Antennal toruli (tor) distinctly above ventral edge of eyes; vertex and occiput densely reticulate; frons with median longitudinal line; malar sulcus (msl) present and straight; mandible tridentate; foramen magnum situated at normal position.
Thorax with pronotum slightly reticulate. Notauli complete. Midlobe of mesoscutum with median line indicated at least posteriorly (although it may be sometimes faint and difficult to see) and with 1-3 short adnotaular setae on each side. Scutellum with two pairs of short setae and with second pair (2st) of longitudinal lines sometimes deep and margined. Propodeum with median carina replaced by groove anteriorly or sometimes appearing forked; paraspicular carinae (psc) more or less distinct, sometimes Y-shaped. Spiracles (spr) very small, subcircular, separated by about their diameter from hind edge of metanotum, whole rim exposed.
Petiole distinct, longer than broad, sometimes with carinae. Gaster with cercal setae subequal in length or one seta longer than the others.
Body black to brown, without pale markings.

Species of this genus were recorded in Holartic and Oriental regions (Noyes, 2001).

Mischotetrastichus belongs to the subfamily Tetrastichinae, as it has female funicle 3 and male 4-segmented, notauli complete, ventral plaque on male scape and postmarginal vein reduced.
This genus was described by Graham (1987) using Tetrastichus petiolatus Erdös (the only species recognised at the time) as type-species. Moreover, Graham, in the same paper, recognised a misidentification of two species of Ceratoneura Ashmead (C. erdoesi Kostjukov and C. alolica Kostjukov), which thus were both synonymised with T. petiolatus.
Mischotetrastichus can be confused with Citrostichus Boucek, Oomyzus Rondani, Quadrastichus and Tetrastichus Haliday, as all these tetrastichinae genera have one single seta on submarginal vein. Quadrastichus, Oomyzus and Tetrastichus can be distinguished by not having a distinct and sculptured petiole; Oomyzus also doesn’t have funicular segments longer than broad. Citrostichus, the closest genus to Mischotetrastichus, may be distinguished by having the propodeal spiracles partially covered by callus, foramen situated very low and gaster with a whitish spot placed basally in both sexes (Kamijo & Ikeda, 1997).
Keys of this genus are available only for the Japanese species (Kamijo & Ikeda, 1997).

Diagnosis

Distribution

Biology