Perithreticus Vaillant 1973
Creators: name: Kvifte, Gunnar Mikalsen
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Psychodidae
Perithreticus

description: Perithreticus Vaillant, 1973
Perithreticus Vaillant, 1973: 355. Type species: Psychoda bishoppi Del Rosario, 1936, by original designation.
Diagnosis. Eyebridge of four rows of facets; labellum bulbous, setose; antennal flagellomeres nodiform with Yshaped ascoids; flagellomeres 11–14 or 13–14 without internodes, diminutive (Fig. 1 C); clypeus margin with a Ushaped median anterior concavity (Fig. 1 A); thorax (Fig. 1 E) with anepisternum subrectangular, delimited by clear dorsal suture, with large spiracle anteriorly; anepimeron subtriangular; tarsi without dorsal projection (Fig. 1 D); wing (Fig. 1 D) with upper margin of R1 strengthened and area between C and R1 infuscated; wing membrane with micropilosity only; aedeagus bilaterally symmetrical, consisting of two phallomeres connected by a membrane to form a spatula; flanked by two subtriangular parameres (Fig. 1 F); parameres arising from dorsal side of gonocoxal condyles, connected to anterior end of ventral epandrial plate; gonocoxal condyles pointed, almost meeting at median; hypoproct (Fig. 1 G) broad, wrinkled and pilose, reaching over the bases of both surstyli, concave anteriorly; surstyli with 7 to 12 tenacula arranged in a single unspaced transverse row distally.
Discussion. Perithreticus Vaillant, 1973 was defined briefly in a key to Nearctic " Telmatoscopini of the Threticus group" (Vaillant 1973) and has not been in use since. The records presented in the present paper are the first of the genus from the Afrotropical region and indeed from anywhere outside the Nearctic. Two species described from Papua New Guinea, Philosepedon forcipata Quate & Quate, 1967 and P. pectinata Quate & Quate, 1967, may also belong to Perithreticus; however this must be confirmed by reexamination of Quate & Quate's (1967) material.
Vaillant (1973) also placed Psychoda jonesi Quate, 1955 in the genus, possibly based on a similar number and arrangement of tenacula. However, this species differs markedly from the type species P. bishoppi; exhibiting several character states that do not fit with the generic diagnosis; including an asymmetrical aedeagus with a single paramere and ascoids with a single anterior branch.
An apomorphic character uniting the Nearctic type species P. bishoppi with the new Tanzanian species described herein is the characteristic shape of the hypoproct, which is M-shaped and finely pilose in both species. Although this character has yet to be surveyed extensively within Psychodini it appears to be unique to Perithreticus based on current knowledge. Another unusual character within Psychodini is the arrangement of the tenacula in a transverse distal row with bases touching. This is, however, also seen in Rhipidopsychoda Vaillant (see below) and in the Tanzanian Threticus species Threticus tanganicus Wagner & Andersen, 2007. In Threticus, most described species have the tenaculum bases separated by the width of approximately 1–2 tenaculum base widths, however; the polarity of this character within Psychodini and Psychodinae is unclear.
description: Published as part of Kvifte, Gunnar Mikalsen, 2015, The Afrotropical genera of Psychodini: Redefinition of the tribe, first Afrotropical record of Perithreticus Vaillant, 1973 and description of Soeliella gen. nov. (Diptera: Psychodidae: Psychodinae), pp. 115-126 in Zootaxa 3986 (1) on pages 117-118, DOI: 10.11646/zootaxa.3986.1.6, http://zenodo.org/record/236377