Phelister gregarius, 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

37. Phelister gregarius sp. nov. Figs 23A, B , 24A-F , Map 14

Type material.

Holotype male: " Peru: Dept. Loreto, Iquitos - Nauta rd., km 58, Rio Itaya at 4°15.738'S, 73°28.052'W [-4.2563, -73.4675]. 120m" / "Window trap next to entrance into Eciton burchelli statary bivouac in a hollow tree 5-9 May 2009. A.V.Petrov" / "Caterino/Tishechkin Exosternini Voucher EXO-00466 (FMNH). Paratypes (46): Peru: same data as type (22ex.); Loreto, Iquitos (-3.74, -73.27), 90 m, 5/5/92, FIT, J. Danoff-Berg, EXO-03341 (SEMC, 1ex.); Loreto, km 63, rd. Iquitos - Nauta, Rio Itaya (-4.2534, -73.4346), 140 m, 2/10/10-2/14/10, A.V. Petrov, EXO-03340 (AKTC, 1ex.); Ecuador: Orellana, Est. Cientifica Yasuní, mid. Rio Tiputini (-0.675, -76.4), 6/28/99-7/5/99, FIT, C. Carlton & A. Tishechkin, LSAM 0045453 (LSAM, 1ex.); Orellana, Est. Cientifica Yasuní (-0.675, -76.4), 7/11/08-7/26/08, FIT, A. Tishechkin (AKTC & LSAM, 5ex.); Orellana, Est. Cientifica Yasuní (-0.675, -76.4), 7/18/99, Berlese of litter and refuse deposit at Eciton burchelli bivouac site just after emigration, A. Tishechkin, EXO-00730 (AKTC, 1ex.); Orellana, Est. Cientifica Yasuní (-0.675, -76.4), 7/13/08, Sifting litter at recently abandoned bivouac site of Eciton burchelli statary phase colony, A. Tishechkin (AKTC, 3ex.); Orellana, Est. Biodiv. Tiputini (-0.64, -76.15), 7/29/08-8/3/08, FIT, A.K.Tishechkin (AKTC, 3ex.); Orellana, Est. Biodiv. Tiputini (-0.64, -76.15), 8/3/08-8/6/08, FIT, LSAM Team (LSAM, 2ex.); Colombia: Vaupes, Est. Biol. Caparu, Rio Apoporis (-1.1, -69.5), 9/27/95-12/1/95, FIT, Black-water terrace forest on sandy soils, B. Gill (AKTC, 3ex.); Vaupes, Parco Nac. Mosiro-Itajura (Caparu), Centro Ambiental (-1.0667, -69.5167), 60 m, 1/20/03-1/30/03, FIT, D. Arias & M. Sharkey (AKTC, 1ex.).

Other material.

Bolivia: Santa Cruz, Amboro National Park, Los Volcanes (-18.1, -63.6), 1000 m, 11/20/04-12/12/04, FIT, Mendel H. & Barclay, M.V.L. (NHMUK, 2ex.); Brazil: Amazonas, Reserva Ducke, AM-010, km 26 (-3, -59.94), 12/2/77, J. Arias, EXO-03349 (USNM, 1ex.); Pará, Altamira - Marabá: km 18 (-3.15, -52.05), May 1984, FIT, EXO-03348 (CHND, 1ex.); Paraná, Piraquara (-25.4961, -48.9817), 9/3/07-9/10/07, P. Grossi, EXO-03347 (DZUP, 1ex.); Rondonia, Rio Jamari (-8.7833, -63.7), 12/1/88-12/12/88, FIT, EXO-03350 (CHND, 1ex.); Costa Rica: Puntarenas, Est. Biol. Las Alturas, Coto Brus (8.95, -82.8667), 1550 m, 3/25/03-3/30/03, FIT, A. Cline & A. Tishechkin, EXO-03343 (LSAM, 1ex.); Puntarenas, Est. Biol. Las Cruces (8.7833, -82.9583), 1100 m, 4/10/02, Sifting at recently abandoned bivouac site of Eciton burchelli nomadic phase bivouac, A. Tishechkin, EXO-00744 (LSAM, 1ex.); Puntarenas, Est. Pittier, Coto Brus, Senderos Pittier y Pelton (9.06, -82.93), 1670 m, 11/7/99, R. Gonzalez, INB0003153030 (INBIO, 1ex.); Puntarenas, San Vito Las Cruces (8.8, -83), 1200 m, 7/1/82-7/30/82, FIT, B. Gill, EXO-03344 (AKTC, 1ex.); San Jose, Cloudbridge Reserve, 2.4 km ENE Sn Gerardo de Rivas, Ridge trail (9.4678, -83.564), 2050 m, 6/9/04-6/12/04, FIT, J. Ashe, Z. Falin, I. Hinojosa, SM0659028 (SEMC, 1ex.); French Guiana: Régina, Rés. Natur. des Nouragues, Camp Inselberg (4.0833, -52.6833), 1/25/11, FIT, SEAG, EXO-03351 (CHND, 1ex.); Belvédère de Saül, point de vue (3.6228, -53.2094), 1/31/11, FIT, SEAG (CHND, 1ex.); Panama: Chiriqui, 27.7 km W. Volcan Hartmann’s Finca (8.75, -82.8), 1450 m, 6/14/95-6/17/95, FIT, J. Ashe & R. Brooks, EXO-03352 (SEMC, 1ex.); Chiriqui, 4 km N Sta. Clara Hartmann’s Finca (8.75, -82.8), 1500 m, 6/30/82-7/13/82, FIT, B. Gill (AKTC, 2ex.); Darien, Cana Biological Station, Serrania de Pirre (7.755, -77.685), 1380 m, 6/4/96-6/7/96, FIT, J. Ashe & R. Brooks, SM0050908 (SEMC, 1ex.); Panama, Chepo-Charti Rd. (9.28, -79.1), 400 m, June 1982, FIT, B. Gill, EXO-03353 (CNCI, 1ex.); Peru: Junín, Pampa Hermosa Lodge, 22 km N San Ramon (-10.9883, -75.425), 1220 m, 11/14/07-11/27/07, FIT, D. Brzoska, SEMC0869361 (SEMC, 1ex.); Junín, 11 km NE Puerto Ocopa, Los Olivos (-11.05, -74.2587), 1200 m, 3/26/09-3/31/09, FIT, A. Petrov & A. Tishechkin (AKTC, 5ex.); Madre de Dios, Rio Los Amigos CICRA(Puerto) (-12.5709, -70.1018), 230 msm, 8/5/06, Colectados en: basurero de Eciton sp., A. Asenjo (MUSM Lima, 3ex.); Cusco, Villa Carmen Fld Stn., 12.89221°S, 71.41946°W, 555 m, 20-30.V.2011, DJ Bennett, FIT (SEMC, 1ex.); Suriname: Brokopondo, Ston Eiland Eco Resort nr. Brownsberg (4.9833, -55.1333), 2/10/10-2/13/10, FIT, C. Gillet, P. Skelley, W. Warner, EXO-03345 (FSCA, 1ex.); Pará, 11 km SE Zanderij Airport (5.3933, -55.1581), 30 m, 6/20/99, FIT, Z. Falin, EXO-03346 (CMNC, 1ex.); Venezuela: Amazonas, Cerro de la Neblina, base camp (0.8333, -66.1667), 140 m, 1/26/85-1/31/85, FIT, R.A. Faitoute, P.J. & P.M. Spangler & W.E. Steiner (USNM, 1ex.).

Diagnostic description.

Length: 1.22-1.54 mm (avg. 1.39 mm); width: 1.14-1.26 mm (avg. 1.20 mm). Body elongate oval, rufescent, smooth, but with conspicuous ground punctation throughout; frons depressed along midline; supraorbital stria present, ends free; frontal stria complete, fine at middle; epistoma with edges raised but not subcarinate; labrum emarginate; mandibles lacking basal teeth; prescutellar impression subtriangular, with basal corners rounded, ~ 2 × as wide as scutellum; median pronotal gland openings ~ 2/3 behind anterior margin, distinctly annulate; pronotal disk with few sparse secondary punctures at sides, most slightly elongate and separated by their lengths or more; marginal pronotal stria complete along lateral and anterior margins, crenulate in front; submarginal stria short, present only in anterior corners, rarely absent; elytron with single, complete epipleural stria; outer subhumeral stria nearly complete, slightly abbreviated at base, inner subhumeral absent; dorsal striae 1-4 complete, 5th present in apical 3/4 and as short basal arch, sutural stria present in apical 2/3; propygidium with dense, coarse secondary punctation; pygidium with ground punctation enlarged and dense; prosternal keel barely emarginate at base, striae converging sinuately to near apex; apex of keel abruptly narrowed at junction with prosternal lobe; prosternal lobe short, with complete marginal stria; mesoventrite weakly produced, with weak, complete marginal stria interrupted laterally by mesocoxa; postmesocoxal stria ending at middle of lateral portion of metaventrite; mesometaventral stria broadly arcuate across middle, reaching middle of mesoventrite, offset laterad at sides from lateral metaventral stria; lateral metaventral stria extending from mesometaventral suture to near middle of metacoxa; metaventrite with few secondary punctures near metacoxa, that of male weakly depressed at middle and with very short scale-like vestiture; 1st abdominal ventrite coarse secondary punctation in anterior 1/2, with fragmented but nearly complete lateral stria along inner margin of metacoxa; protibia rather slender, outer margin weakly dentate, with five or six marginal spines, apical corner with distinct emargination; protarsi of male with flattened ventral setae; meso- and metatibiae slender, with rather long, fine marginal spines. Male: basal piece narrow, elongate, ~ 1/2 length of tegmen; tegmen with sides unevenly subparallel in basal 2/3, abruptly narrowed to ventrally curving apices; medioventral process present, projecting at basal 1/3 of tegmen, divided at middle; median lobe ~ 1/2 tegmen length, very narrow.

Etymology.

This species name refers to its apparent predilection for socializing with army ant colonies, from which several records originate.

Distribution.

This is a relatively common species, known from many specimens over a broad area from Costa Rica south to Peru, and east to Paraná, Brasil.

Remarks.

Despite this species’ wide range, it is relatively consistent in morphology, and readily identifiable, by the rounded triangular shape of its prescutellar impression, relatively sparse lateral secondary punctures on the pronotum, and presence of only a short fragment of the submarginal pronotal stria in the anterior corners. It also appears to be unique in showing a distinct sexual dimorphism, with the males’ metaventrite being medially depressed as well as bearing a field of very short, almost imperceptible, scale-like setae. A few other species show a faint depression in males, but none as distinct as here.

Two specimens from Santa Cruz, Bolivia, and one from Junín, Peru have a complete lateral submarginal pronotal stria, and have pronotal microsculpture (like P. rudis ), but have sparser dorsal sculpturing and an unbroken anterior marginal pronotal stria, so are ambiguous. We place these here for now, but additional material will be necessary to fully assess patterns of character variation. Specimens from Suriname have the lateral submarginal pronotal stria almost absent, represented by only a very short arc in the anterior corners.

Figures

Map 14. Collecting records for Phelister gregarius (circles), P. rudis (black squares), and P. incongruens (stars).

Figure 23. A, B Phelister gregarius: A dorsal habitus B ventral habitus C, D P. praecisus: C dorsal habitus D ventral habitus E-G P. rudis: E dorsal habitus F ventral habitus G anterior view of protibia.

Figure 24. Male genitalia A-F Phelister gregarius: A tergite 8 B sternite 8 C tergites 9 & 10 D sternite 9 E aedeagus, dorsal F aedeagus, lateral G, H P. praecisus: G aedeagus, dorsal H tegmen, lateral I, J P. rudis: I aedeagus, dorsal J tegmen, lateral.