Diochus inornatus SHARP, 1885

Irmler, Ulrich, 2017, A review of the Neotropical genus Diochus ERICHSON, 1840 (Coleoptera: Staphylinidae: Staphylininae), Beiträge Zur Entomologie = Contributions to Entomology 67 (1), pp. 1-62 : 13-14

Diochus inornatus SHARP, 1885

Figs 8A–C , 38F , 41G

Diochus inornatus SHARP, 1885: 466

Type material examined: 2 syntypes: Panama, male, Bugaba 800–1000 feet elevation, leg. Champion ( BMNH); female, Pena Blanca, 3000–4000 feet, leg. Champion ( BMNH) .

Further material examined: Mexico: Veracruz, 10 mi. W Coatzacoalcos , male, 15.8.1966, leg. J.&W. Ivie ( AMNH) ; Oaxaca, 10.8 mi S Valle Nacional, Hwy 175, under bark, montane tropical forest, 1000 m elev., male, 26.4.1977, leg. J. Ashe ( FMNH) ; Jalisco, Puerto Mazos, 100 mi SW Autlán, 4400 ft. elev., Berlese , litter oak tropical decid. forest, 2 females, 25.9.1973, leg. A. Newton ( FMNH) ; Nicaragua: Rio San Juan Dept. , 60 km SE San Carlos, Refugio Bartola (84°20.30'W, 10°58.40'N), 100 m elevation, collected by mercury vapor/UV light, male, 30.5.2002, leg. R. Brooks, Z. Falin #NIC1BFC02 129 ( KNHM) ; Costa Rica: Limon Prov., Rd. Bribri> Bratsi (9°33.45'–35.45'N, 83°52.30'–53.17'W), 30–50 m elevation, along river bank, secondary forest, Fincas , car net, male, 2.12.2013, leg. M. Schülke & B. Grünberg ( MSC) ; Rd. Barrigones (Osa)> Chacarita (8°35'-48'N, 83°15'-26'W), 0–250 m elevation, pastures, plantages, devasted forest, car net, male, 11.12.2012, leg. Schülke & Grünberg ( MSC) ; Osa peninsula, Rd. Drake> Rincon de Osa (8°41'-42'N, 83°29'-40'W), 0–400 m elevation, car net, male, 9.12.2012, leg. Schülke & Grünberg ( UIC) ; Vulcan Rincon e la Vieja, Rd. Hacienda Guachipelin> Santa Maria (10°42.43'-45.11'N, 85°20.15'-22.45'W), 500 –700 m elevation, dry forest & pasture, car net, female, 4.12.2012, leg. Schülke & Grünberg ( UIC) ; Alajuela, San Ramon, 5 km W, 1200 m elevation, 1 male, 1.– 31.7.1997, leg. P. Hanson #CR1HAN92-97 ( KNHM) ; Puntarenas, R.F. Golfo Dulce, 24 km W Piedras Blancas , 200 m elevation, 1 male, Jan.–Feb. 1992, leg. P. Hanson ( KNHM) ; S.M. Barranca , male, 12.– 16.2.1940, leg. A. Bierig ( FMNH) ; San Mateo, Jesus Maria, male, 27.10.1939, leg. A. Bierig ( FMNH) ; Desmonte , 500 m elev., male, 28.2.– 2.3.1939, leg. A. Bierig ( FMNH) ; Panama: Chiriqui Prov., 2 km S Cuernavaca Camp, Rincon Vly. , litter on semi-cleared hillside between rock & log, 1 male, 1 female, 16.1.1981, leg. W. Suter ( FMNH) ; Panama Prov. , SW of Campana, Cerro Campana (8°40.54'N, 79°55.28'W), litter near stream, 750 m elev., female, 24.5.2001, leg. L. Herman & W. Opitz ( AMNH) ; Chiriqui Prov., Qda., Laguna nr. Rio San Felix , 725 m elev., litter on sand pocket S. bank, 4 males, 4 females, 19.1.1981, leg. W. Suter ( FMNH) ; Bocas del Toro Prov., Almirante , forest floor litter, female, 1.4.1959, leg. H.S. Dybas ( FMNH) ; Bugaba , 800–1500 ft. elev., leg. Champion ( FMNH, exchange with BMNH) ; Colombia: Meta, PNN Tinigua, Caño Nevera (73°48'W, 2°11'N), 390 m elevation; malaise trap, 1 female, 23.1.– 7.2.2002, leg. C. Sánchez #M2330 ( KNHM) ; Vichada, PNN El Tuparro, Cerro Tomás (67°51'W, 5°21'N), 140 m elevation, malaise trap, 1 female, 22.5.– 3.6.2001, leg. I. Gill #M1789 ( KNHM) ; French Guiana: Caussade (52°57'W, 5°10'N), car net, 5 males, 18 females, 6.11.20122, 7.11.2011, leg. T. Struyve (10 TSC, 13 UIC); Coralie (52°21'W, 4°30'N), car net, 2 females, 15.11.2011, leg. T. Struyve (1 TSC, 1 UIC); Barrage de Petit Saude (53°02'W, 5°03'N), car net, female, 15.11.2011, leg. T. Struyve ( TSC) ; Ecuador: Sucumbios, Sacha Lodge (0°5'S, 76°5'W), 270 m elev., malaise trap, female, 14.– 24.3.1994, leg. Hibbs ( KNHM) ; Brazil: Pará , 5 km E Belém, soil-litter layer in primary “terra firme” forest, male, 30.5.1973, leg. R.T. Schuh ( AMNH) ; 8 km E Belém, Ananindéua, secondary growth forest, Plot #2, 3 females, 30.6.1973, leg. R.T. Schuh ( AMNH) ; Minas Gerais, Pampulha , UFMG campus, BH (19°52'S, 43°58'W), 830 m elev., malaise trap, female, 27.11.1996, leg. J.C.R. Fontenelle #BRA1 F96097 ( KNHM) .

Diagnosis: The species is characterised by the thick and long seminal vesical of the endophallus and the apical coiled duct similar as in D. hanagarthi . But the seminal vesical is still thicker and longer than in D. hanagarthi . The coiled apical duct is nearly on the same level as the upper edge of the seminal vesical. The head is smaller and more elongate than in D. hanagarthi and the temples are longer, approximately 2.5 times as long as eyes. EL: HL is only 0.21 in D. inornatus , but 0.29 in D. hanagarthi .

Description: Length: 3.8–4.1 mm. Colouration: dark to light brown; pronotum lighter brown to dark orange; posterior margin of elytra slightly lighter brown; legs and base of antennae light brown to yellowish; apical antennomeres slightly darker.

Head: 0.56 mm long, 0.44 mm wide; eyes not prominent; small; temples twice as long as eyes; EL: HL = 0.21; temples approximately parallel; PW: EW = 1.10; posterior angles widely rounded; neck one third as wide as head; clypeus impunctate; anterior vertex with two irregular rows of deep setiferous punctures from anterior edge of eyes to half distance between eyes and neck; three to four punctures in each row; postocular area with more setiferous punctures; posterior vertex with few weaker and sparser setiferous punctures; without microsculpture; surface shiny.

Antennae as long as head and half of pronotum combined; first antennomere slight thicker than antennomeres two and three; basal three antennomeres more or less conical; one third longer than at their apical width; following antennomeres approximately quadrate; apical antennomeres slightly wider than long; all antennomeres pubescent and with few longer apical setae.

Pronotum: 0.68 mm long, 0.50 mm wide; sides parallel; lateral margin extremely fine; nearly invisible in dorsal aspect; anterior and posterior angles widely rounded; with very sparse setiferous punctation; narrow midline impunctate; two rows of three to four setiferous punctures adjacent to midline; in anterior half distance between punctures wider than in posterior half; another row of punctures laterad and between both rows few single punctures; without microsculpture; surface shiny.

Elytra: 0.66 mm long, 0.68 mm wide; widest close to posterior margin; shoulders obtuse; setiferous punctation partly in longitudinal rows; first row of punctures adjacent to suture; lateral rows irregular; surface weakly coriaceous; less shiny than head and pronotum.

Abdomen with dense pubescence; among pubescent punctation with few longer setae.

Aedeagus thick; seminal vesical long and thick; at least three fourth as long as total length of central lobe; basal inner duct looped; apical inner filamentous duct shortly coiled; paramere short and narrow; elongate and without prominences; three long setae at apex close together.

Spermatheca: 0.41 mm long, 0.22 mm wide; bursa copulatrix in asymmetric position of coiled oval duct; sides of coiled duct parallel at middle.

Figures

Figs 41: Fore-bodies of Diochus longicornis (A), D. tarsalis (B), D. adisi (C), D. ashei (D), D. guianensis (E), D. unicolor (F), D. inornatus (G), D. hanagarthi (H); scale bar: 0.5 mm.

Figs 6–9: Diochus longicornis-group: Diochus ashei (6), D. unicolor (7); Diochus inornatus-group: D. inornatus (8), D. hanagarthi (9); aedeagus (A), paramere (B) and antenna (C); scale bar: A, B: 0.1 mm, C: 0.2 mm.

Fig. 38: Spermathecae of Diochus longicornis-group: D. longicornis (A), D. tarsalis (B), D. ashei (C), D. guianensis (D), D. unicolor (E); Diochus inornatus-group: D. inornatus (F), D. hanagarthi (G), D. antennalis (lateral aspect H), D. hermani (I), D. hibbsi (J), D. newtoni (K), D. novus (L); scale bar: 0.1 mm.