Brachygluta (Brachygluta) kiowa Sabella

Chandler, Donald S., Sabella, Giorgio & Bückle, Christoph, 2015, A revision of the Nearctic species of Brachygluta Thomson, 1859 (Coleoptera: Staphylinidae: Pselaphinae), Zootaxa 3928 (1), pp. 1-91 : 71-73

26. Brachygluta (Brachygluta) kiowa Sabella , sp. n.

( Figs 31 , 43 A)

Material examined, 18 specimens. HOLOTYPE male: USA: Kansas: Meade Co.: //KANSAS: Meade Co., Jct. Cimarron Riv. & Hwy, 23. VI-25-1992, E. Riley, night sweep/ [red label] HOLOTYPE Brachygluta kiowa Sabella / / ( TAMU). PARATYPES, 17: eutopotypical ( DSCC, 5M, 1F; TAMU, 5M). Colorado: Fremont Co.: Canon City, IV-2-1900 ( FMNH, 2M). New Mexico: Chaves Co.: Bottomless Lakes S.(tate) P.(ark), VIII-7-1989, Y. Bousquet, gypsum flats ( CNCI, 1M). Texas: Comanche Co.: Proctor and nearby farms, VI-24-1976, J.W. Smith & A.R. Hardy ( CSCA, 1M). Hemphill Co.: Gene Howe WMA, V-20-2006, R. Turnbow, mv + bl ( DSCC, 1M). Randall Co.: Palo Duro Cyn. St. Pk., VI-25-1995, Godwin, Marqua, & Wolfe, UV ( TAMU, 1M).

Description. BODY: Length 1.72–2.00 mm; orange-brown to brown; setae on head and pronotum short, curved and suberect, over rest of body longer and decumbent. Head: surface smooth, shining, punctures indistinct. Antennomeres III-VI longer than wide, VII as long as wide, VIII slightly transverse, IX as long as wide, X slightly longer than wide, VIII about two-thirds width of IX ( Fig. 31 D). Setose are of median vertexal fovea slightly smaller than those of lateral foveae. Pronotum: surface smooth, shining, punctures indistinct. Setose area of median antebasal fovea varying from about same size to about two-thirds size of lateral antebasal foveae. Elytra: with faint microreticulation, punctures indistinct, discal stria extending to about four-fifths of elytral length. Abdomen: disc smooth, shining, punctures indistinct; basal striae of tergite 1 about one-fourth paratergite length, slightly divergent, separated at base by one-half tergite width; setose brush between bases of striae short.

MALE: Antennae and trochanters not modified. Metaventrite with triangular setose patch arising between metacoxae present but not distinct. Tergite 1 with apex deflexed in middle third, appearing slightly emarginate at middle, setae along apex longest in areas of deflexed area and obscuring it ( Figs 31 A–B), in lateral view tergite 1 only slightly protruding above base of tergite 2; tergite 2 with slightly arcuate transverse carina at base below apex of tergite 1, area anterior to carina impressed, disc at middle posterior to carina with two shallow longitudinal impressions that diverge slightly toward apex, impressions vary from distinctly bifoveate to obscure ( Figs 31 A–C); in lateral view tergite 1 with disc convex, 2 flat, 1–4 close to confluently curved. Abdominal ventrites broadly rounded. Metatibiae thin, narrow at base, gradually widened to near apex, mesal margin of apical fifth with brush present ( Fig. 31 E). Aedeagus 0.42 mm long; with dorsal plate abruptly narrowed in apical half to form elongate thin finger-like lobe; parameres with distinct preapical constriction, with three thickened setae on lateral margin at anterior angle of constriction, flattened hyaline seta near mesal margin, thickened to middle and aciculate to apex; internal sac with two large curved spines ( Fig. 31 F).

FEMALE: Lacking modifications of the abdominal tergites, otherwise similar to the male, including presence of the metasternal patch of setae.

Collecting data. The one series was collected by sweeping at night along a river; individuals were taken due to their attraction to ultraviolet light, and one was found in an area of gypsum flats. Specimens were taken from April to August.

Distribution ( Fig. 43 A). Collected in the shortgrass prairie area of the southern portion of the plains states from Kansas to west Texas.

Comments. This species is distinct in the form of male tergites 1 and 2. Tergite 1 has the apical margin slightly deflexed at the middle, and tergite 2 has a quadrate impression of varying distinctness, defined laterally by the two shallow longitudinal impressions. The two lateral impressions in the broader impression of the basal portion of male tergite 2, plus its distribution in the high plains near the Rocky Mountains leads to the ready recognition of this species. Closest is B. chisos , which has a semicircular basal area of tergite 2 roughened and indistinct flattened/ modified, but this area reaches only to the midpoint of the disc and the discal impressions of B. kiowa are suggested but are much shorter.

Etymology. The name is based on the name of one of the native American groups that lived in the area that this species occurs.

Figures

FIGURE 31. Brachygluta kiowa Sabella. A: Abdomen, dorsal view (Kansas, Meade Co., paratype). B: Abdomen, dorsocaudal view (Kansas, Meade Co., paratype). C: Abdomen, caudal view (Colorado, Fremont Co., paratype). D: Right antenna (Kansas, Meade Co., paratype). E: Left metatibia, anterior view (Kansas, Meade Co., paratype). F: Aedeagus (Kansas, Meade Co., paratype).

FIGURE 43. Distribution map of Brachygluta mormon species-group. A: Brachygluta kiowa Sabella. B: Brachygluta mormon Bowman. C: Brachygluta mayo Sabella. (Red dot: material examined, green dot: only state on label).