Thoasia Liebke, 1939

Erwin, Terry L. & Aldebron, Charlotte, 2018, Neotropical Thoasia Liebke, 1939 and Straneotia Mateu, 1961 of the Cryptobatida group, subtribe Agrina: Taxonomic revisions with notes on their ways of life (Insecta, Coleoptera, Carabidae, Lebiini), ZooKeys 742, pp. 57-90 : 61-62

Thoasia Liebke, 1939 Pentagonal arboreal carabid beetles Figs 1 , 2 , 3 , 4

Thoasia Liebke, 1939:129.

Type species.

Thoasia rugifrons Liebke 1939, by monotypy. Type area. Venezuela.

Diagnosis.

(cf. Figs 1 , 2 , 3 , 4 ). Neck constricted, width less than that of base of pronotum; eyes moderately large, not hemispherical; frons moderately rugose, more or less anteriorly depressed. Prothorax more or less subequal in width to that of the head across eyes; sides of pronotum narrowly reflexed throughout, more broadly reflexed and markedly angulate at mid-lateral setigerous pore. Elytron at basal third not depressed, surface even, disc striate and punctate. Flight wings of a dusky color. Basitarsus of mid and hind legs markedly elongate, co-equal to length of tarsomeres 2-5; claws serrate. Male only with two rows of white adhesive setae on venter of tarsomeres 1-3; both sexes with long hooked white setae on tarsomere 5. Male with a pair of setae each side on abdominal sternum VII; female with 3 setae each side on abdominal sternum VII. Male endophallus without flagellum.

Dispersal potential.

The wings are fully developed in adults of all known species, thus it is likely these beetles are moderate to strong flyers.

Geographic distribution.

A widespread Neotropical genus known from Colombia, south to southeastern Brazil, in the west to Bolivia, and northeast to French Guiana.

Ways of life.

Little is known about the species in this genus and the little that is known is reported here for the first time. Adults of one species are regularly collected in both the wet and dry seasons using insecticidal fogging techniques in many species of trees reaching the forest canopy in the Amazon Basin, thus they are certainly most times arboreal. They are good flyers as evidenced by their capture in FITs in French Guiana.

Notes.

Only one species has been previously described in this genus from Venezuela and from only one specimen. Adults of the species most commonly collected in canopy samples in Ecuador and Perú were misidentified as T. rugifrons Liebke, but that species is only known to be from Venezuela and French Guiana. To date, the most common species in canopy samples is described below, as new.

References.

Liebke 1939; Erwin 1991.

Included species.

The species list below, as well as the arrangement of descriptions that follows, is ordered alphabetically within two species groups.

rugifrons species group

Thoasia rugifrons Liebke, 1939, French Guiana, Venezuela.

Thoasia surinamensis Erwin & Aldebron, sp. n., Suriname.

Thoasia pterosmaragdos Aldebron & Erwin, sp. n., French Guiana.

manu species group

Thoasia manu Erwin & Aldebron, sp. n., Ecuador, Perú.

Figures

Figure 1. Digital Photo-illustrations. Habitus, dorsal aspect: A Thoasia rugifrons Liebke, female, ADP 148165 B Thoasia pterosmaragdos Aldebron & Erwin, sp. n., female, ADP 148174 C Thoasia manu Erwin & Aldebron, sp. n., female, ADP 100320. Scale bar: 1.00 mm.

Figure 2. Digital Photo-illustrations. A Habitus, dorsal aspect: Thoasia surinamensis Erwin & Aldebron, sp. n., female, ADP 112239. Scale line = 1.00 mm B Female reproductive system dorsal aspect: Thoasia manu, Erwin & Aldebron, sp. n., ADP 100301. Legend, bc, bursa copulatrix; sg, spermathecal gland; sgd, spermathecal gland duct; sp., spermatheca; lt, laterotergite; co, common oviduct; gc 1, gonocoxite 1; gc 2, gonocoxite 2, des, dorsal ensiform seta, b, base of gonocoxite 2; bl, blade of gonocoxite 2. Scale bar: 0.50 mm.

Figure 3. Digital Photo-illustrations, male aedeagus in repose, dorsal, ventral, left lateral aspects: A Thoasia rugifrons Liebke, ADP 152522 B Thoasia pterosmaragdos Aldebron & Erwin, sp. n., ADP 13748 C Thoasia manu Erwin & Aldebron, sp. n., ADP 100336. Legend, lp, left paramere; rp, right paramere; pb, phallobase; bo, phallobase orifice; ps, phalloshaft; a, phalloapex; ml, median lobe. Scale bar: 0.50 mm.

Figure 4. Digital Photo-illustrations. Habitus, dorsal aspect. A Straneotia cylindroceps Erwin & Aldebron, sp. n., female, ADP 100396 B Straneotia moi Aldebron & Erwin, sp. n., female, ADP 141236 C Straneotia confundis Aldebron & Erwin, sp. n., male, ADP 152452 D Straneotia amazonica Mateu, Holotype female. Scale bar: 1.00 mm (A-C); ABL = 5.5 mm (D).