Phelister incertus, Caterino & Tishechkin, 2020

Caterino, Michael S. & Tishechkin, Alexey K., 2020, Recognition and revision of the Phelister blairi group (Histeridae, Histerinae, Exosternini), ZooKeys 1001, pp. 1-154 : 1

54. Phelister incertus sp. nov. Figs 36A, B , 37A, B , Map 18

Type material.

Holotype male: " Bolivia: Santa Cruz Dep., 3.7 km SSE Buena Vista, Flora y Fauna Hotel 17°29.9'S, 63°33.2'W [-17.4987, -63.6521], 400-440 m, F.I.T. 3-9 Nov 2003, R.Leschen # 052" / "Caterino/Tishechkin Exosternini Voucher EXO-00361" (SEMC); Paratypes (35): Bolivia: Santa Cruz, ~ 5 km SSE Buena Vista, Flora y Fauna Hotel (-17.4987, -63.6521), 440 m, 12/14/03-12/24/03, FIT, S & J. Peck (AKTC, 1ex.); Peru: Madre de Dios, Cocha Cashu Bio. Stn., Manu Nat. Park (-11.8958, -71.4067), 350 m, 10/17/00-10/19/00, FIT, R. Brooks, EXO-03548 (CMNC, 1ex.); Madre de Dios, Cocha Salvador, Manu National Park (-12.0036, -71.5267), 310 m, 10/20/00-10/21/00, FIT, R. Brooks, SM0264371 (SEMC, 1ex.); Madre de Dios, Tambopata, Res. Cuzco Amazonico, 15 km NE Pto. Maldonado (-12.55, -69.05), 200 m, 6/13/89-7/16/89, FIT, R. Leschen (SEMC, 32ex.).

Diagnostic description.

Length: 1.42-1.54 mm (avg. 1.51 mm); width: 0.91-1.34 mm (avg. 1.24 mm). Body elongate oval, convex, outline somewhat interrupted at pronotal-elytral junction, with pronotum narrower, rufescent, ground punctation very fine and inconspicuous; frons rather narrow and elongate, along with epistoma weakly depressed; supraorbital stria nearly complete, slightly abbreviated at sides; frontal stria carinate, outwardly rounded, complete; epistoma with sides and front subcarinate, almost appearing striate around edges of depression; labrum weakly emarginate; antennal club short, round, with elongate setose patch on dorsum; prescutellar impression small, elongate oval, narrower than, and about as long as scutellum; pronotal disk with few or no lateral secondary pronotal punctures; marginal pronotal stria complete along sides and front; lateral submarginal pronotal stria complete, arched around anterior corner; pronotal gland openings 3/4 behind anterior margin, widely separated, non-annulate; elytral epipleuron with single, complete stria; outer subhumeral stria in apical 1/3, inner absent; 1st dorsal stria slightly abbreviated from apex, 2nd complete, 3rd complete or interrupted at middle; striae four and five very short, apical, 4th often with short basal fragment, 5th with basal arch connected to base of sutural, sutural stria complete or very narrowly interrupted near base; pro- and pygidium evenly, sparsely covered with conspicuous secondary punctures; prosternal keel weakly emarginate at base, striae weakly divergent anteriorly and posteriorly, free anteriorly; mesoventral process weak, with fine, complete marginal stria; postmesocoxal stria rather long, ending behind outer corner of mesocoxa; mesometaventral stria broadly arched, reaching basal 1/3 of metaventrite, not at all crenulate; lateral metaventral striae divergent toward posterior corner of mesepisternum; protibia with outer margin slightly rounded, weakly dentate, with ~ seven long marginal spines; meso- and metatibiae slender, mesotibia with fairly long marginal spines over most of its length, those of metatibia confined to apical one-third. Male: T10 entire; S8 with few, inconspicuous apical setae; accessory sclerites absent; aedeagus with basal piece slightly> 1/3 tegmen length; tegmen mostly parallel-sided, weakly narrowed to rounded apices; medioventral process present, weak; median lobe 3/4 as long as tegmen, with proximal apodemes undifferentiated.

Etymology.

This species name refers to uncertainty with regard to its systematic placement.

Distribution.

This species is known from several localities in southeastern Peru and Bolivia.

Remarks.

While this species has non-annulate pronotal gland openings, like the preceding two subgroups ( P. curvipes and P. rio subgroups), genitalic characters such as the complete T10 and medioventral aedeagal process make it an awkward fit in either. These characters, in combination with small body size (~ 1 mm), lack of secondary lateral pronotal punctures, and complete, basally hooked sutural stria will distinguish it from other species treated here as well as other Phelister spp.

Figures

Map 18. Collecting records for Phelister incertus (black triangles), P. okeefei (white circle), P. blairoides (white squares), and P. pirana (star).

Figure 36. A, B Phelister incertus: A dorsal habitus B ventral habitus C, D P. okeefei: C dorsal habitus D ventral habitus E, F P. blairoides: E dorsal habitus F ventral habitus G, H P. pirana: G dorsal habitus H ventral habitus.

Figure 37. Male genitalia, Phelister incertus A aedeagus, dorsal B aedeagus, lateral.