Belonuchus oxyporinus ( Sharp, 1885 )

Márquez, Juan & Asiain, Julieta, 2022, Taxonomy of the Mexican species of Belonuchus Nordmann (Coleoptera: Staphylinidae), Zootaxa 5152 (1), pp. 1-129 : 40-41

Belonuchus oxyporinus ( Sharp, 1885)

Figs. 3e, f , 11b , 12f, o , 15b , 18k , 22b , 27a

Philonthus oxyporinus Sharp, 1885: 419 . Belonuchus oxyporinus comb. nov. ex Philonthus (Jiménez-Sánchez et al. 2000) .

Total body length in males 11.9 mm (range 11.2–13.2 mm), in females 11.9 mm (range 9.5–13.1 mm). Black on head, antennae, pronotum, scutellum, prosternum, mesoventrite, anterior and middle coxae, posterior half of sixth visible abdominal segment and abdominal styli. Reddish on elytra, metaventrite, legs (except pro- and meso-coxae), visible abdominal segments 1–5 and anterior half of sixth. Mandibles black at margins and brown toward inner part; maxillary and labial palpi brown.

Head: transverse in males (ratio length/width 0.70, range 0.67–0.77) and in females (ratio 0.83, range 0.80– 0.89). Dorsal surface with sulcate longitudinal midline visible in anterior half of head and front narrowly foveate near anterior margin. Eyes almost 0.5 times the cephalic lateral length, not protruding laterally. Antennomeres 4–5 elongate, 6–10 transverse. Males with mandibles longer than head (ratio 1.37, range 1.17–1.53); females with mandibles almost as long as head (propotion 1.03, range 0.93–1.18); mandibles with two widely separated teeth (basal and middle); mandibular channel well developed, with external and internal margins widely separated at base, internal margin carinate, extending forward beyond level of middle tooth. Apical palpomere of maxillary palpi slightly longer than preapical palpomere; apical palpomere of labial palpi at least 1.25 times longer than preapical palpomere. Head of males wider than pronotum (ratio 1.25, range 1.18–1.32), in females almost equally wide (ratio 1.05, range 0.97–1.08).

Thorax: dorsal rows of pronotum each with five punctures; pronotum almost as long as wide in both sexes (ratio in males 1.07, range 1.03–1.09, in females 1.12, range 1.06–1.15); and almost as wide at anterior corners as at posterior corners (ratio in males 1.03, range 1.00–1.06, in females 1.00, range 0.94–1.01). Scutellum and elytra with fine, moderately dense punctures and setae. Prosternum slightly elevated behind anterior margin, in some large males, a faint transverse carina is visible. Intercoxal process of mesoventrite scutellum-shaped; transverse discal ridge well defined, broadly V-shaped, not meeting margins of intercoxal process laterally ( Fig. 11b ). Profemur of males with external row of spines in no more than its anterior half ( Fig. 12f ), not reaching apex, basal spines small, increasing in size toward apex, but not considerably; internal margin not discernible, with only some short spines near apex. Metatrochanter of males modified like a hook, spine-like in small males proportionately increasing in size with size of specimens, in large specimens the apex of hook resembling a bottle opener, with a tooth or spine at base of its curvature; in large specimens the length of hook covers more than 1/3, but less than 1/2 of length of metafemur ( Fig. 12–o ); metafemur not curved at level of its overlap with the hook, or only weakly curved in larger specimens; metatibia curved at inner part near its apical third only in large specimens, curvature becoming gradually less visible in proportion with the reduction of size of specimens. Tarsomeres moderately flattened dorsally.

Abdomen: visible tergites 1–3 with posterior basal transverse carina well developed, adjacent area slightly to moderately depressed, this area and entire surface of tergites with fine, sparse punctures. Sternites with some widesuperficial punctures combined with fine, sparse punctures. Male pregenital sternite not emarginate at posterior margin ( Fig. 15b ). Male genital sternite short (2.15 times as long as wide), very asymmetrical, anterior portion occupying 39% and posterior portion 61% of its length, apical sinuation very deep ( Fig. 18k ). Abdominal styli slender, slightly flattened at rounded apex.

Aedeagus: length 1.7 mm; oval-elongate shape; apex convex in ventral view and slightly acute in lateral view; with some fine setae in apical posterior part; in ventral view, basal half moderately wider than apical half, in lateral view, basal half notably wider than apical half; internal sac visible in apical third ( Fig. 22b ).

Variability. In addition to the measurements and ratios indicated in the description, and those related to the size of the males, as well as the differences according to sex, the number of punctures in the dorsal rows on pronotum can vary: 5:6, 6:5, 4:5, 5:4; the sixth visible abdominal segment at most is black in the basal half and reddish in the apical half, but in specimens mounted without stretching that segment well, it gives the appearance of having more than the basal half black. Some specimens have few wide-superficial punctures on visible tergites 1–2.

Taxonomic comments. This species is very similar to B. oxyporimimus , in the taxonomic comments of that species it was indicated how to distinguish them. The female holotype of this species was not studied, but we analyzed some photos of this specimen ( Fig. 3e ; NHM, shared by M. Chani Posse), which together with the information of the original description ( Sharp 1885) allowed us to identify this species.

Material examined (184 males, 257 females): Mexico: Chihuahua: “ Urique, Cerocahui , 1750 m, 18 a 21- VII-2006, M. Castillo y L. Delgado cols.” (2, IEXA) . Guerrero: “ Palo Blanco, Sierra del Alquitrán , 1670 m, necrotrampa, 27 a 29-IX-1999, L. Delgado col.” (1, IEXA) . Michoacán: “autopista México-Morelia , km 194, bosque de encino, 2180 m, en hongos podridos, 20-IX-2001, J. Márquez col.” (4, MAAS) . “ Los Azufres, km 4 carretera Los Azufres-Ciudad Hidalgo, ex hongo, J. A. Gómez col.” (1, IEXA) . Morelos: “ Cuernavaca, camino a Mexicapa , bosque de pino-encino, 2300 m, NTP-80 (calamar) #1, mayo de 1993, J. Márquez, E. Córdoba, A. Soria y C. Cabello cols.” (3, MAAS) . Same data, except: “junio de 1993” (5, CC-UAEH; 5, MAAS). Same data, except: “julio de 1993” (5, MAAS) . Same data, except: “noviembre de 1993” (5, MAAS) . Same data, except: “NTP-80 (calamar) #2, 14-VIII-1993 ” (5, MAAS) . Same data, except: “ 12-IX-1993 ” (3, MAAS) . Same data, except: “octubre de 1993” (11, CC-UAEH) . Same data, except: “ 3-X-1993 ” (4, MAAS) . Same data, except: “febrero de 1994” (12, MAAS) . Same data, except: “NTP-80 (calamar) #3, 5-IX-1992 ” (1, MAAS) . Same data, except: “julio de 1993” (1, MAAS) . Same data, except: “octubre de 1993” (2, MAAS) . Same data, except: “febrero de 1994” (1, MAAS) . Same data, except: “NTP-80 (calamar) #4, 24-IV-1993 ” (1, MAAS) . Same data, except: “agosto de 1993” (1, MAAS) . Same data, except: “septiembre de 1993” (2, MAAS) . Same data, except: “ 24-X-1993 ” (7, CC-UAEH; 7, MAAS). Same data, except: “noviembre de 1993” (20, CC-UAEH; 39, MAAS). Same data, except: “febrero de 1994” (17, MAAS) . Same data, except: “NTP-80 (calamar) #5, 5-IX-1992 ” (5, MAAS) . Same data, except: “ 3-X-1992 ” (1, MAAS) . “febrero de 1993” (1, MAAS) . Same data, except: “ 11.VII-1993 ” (5, MAAS) . Same data, except: “agosto de 1993” (7, MAAS) . Same data, except: “septiembre de 1993” (2, MAAS) . Same data, except: “octubre de 1993” (7, MAAS) . Same data, except: “NTP-80 (calamar) #6, junio de 1993” (9, MAAS) . Same data, except: “noviembre de 1993” (2, MAAS) . Same data, except: “febrero de 1994” (2, MAAS) . “ Mexicapa , bosque de pino, zona 1, ex NTP-80 calamar, 25-IV-1993, A. Soria, C. Cabello y E. Córdoba cols.” (1, MAAS) . “ Cuernavaca, Santa María Ahuacatitlán , bosque mesófilo de montaña, 2000 m, en hongos, 30-VII-1996, L. Delgado col.” (1, QJSJ) . “ Tlayacapan, San José de los Laureles , localidad 1, bosque de pino-encino, NTP-80 (calamar), agosto de 1995, J. Márquez col.” (20, CC-UAEH; 25, MAAS). Same data, except: “ K. Villavicencio y J. Márquez cols.” (1, MAAS) . Same data, except: “septiembre de 1995, J. Márquez col.” (4, MAAS) . Same data, except: “octubre de 1995” (26, MAAS) . Same data, except: “septiembre de 1996” (10, CC-UAEH; 26, MAAS). Same data, except: “localidad 2, bosque de pino, agosto de 1995” (1, MAAS) . Same data, except: “septiembre de 1995” (1, MAAS) . Same data, except: “junio de 1996” (1, MAAS) . Same data, except: “diciembre de 1996” (1, MAAS) . Same data, except: “localidad 3, bosque mesófilo de montaña, marzo de 1993” (1, MAAS) . Same data, except: “julio de 1995” (3, MAAS) . Same data, except: “septiembre de 1995” (8, MAAS) . Same data, except: “octubre de 1995” (13, MAAS) . Same data, except: “noviembre de 1996” (1, MAAS) . Same data, except: “en hongos diversos, 15-VIII-1998, R. Toledo y J. Márquez cols.” (3, MAAS) . Same data, except: “en hojarasca, 28-V-2000, J. Márquez y J. Asiain cols.” (1, CC-UAEH) . Same data, except: “localidad 4, bosque tropical caducifolio, agosto de 1996, J. Márquez col.” (12, MAAS) . Oaxaca: “ Ixtlán de Juárez, km 152 a Tuxtepec , N17°20.623´, W96°30.92´, bosque de pino-encino, 1923 m, 16-XI-1999, en excremento vacuno, J. Márquez col.” (1, MAAS) . Same data, except: “en hongo podrido” (2, MAAS) . “ 1.5 km NE de San José del Pacífico , 2248 m, bosque de pino-encino, sobre hongos Amanita , 8-VII-2002, J. Asiain y J. Márquez cols.” (3, MAAS) . “ Santiago Yosondua, camino a Santa María Yolotepec , N16°51´13”, W97°33´43.6”, 2398 m, bosque de pino-encino, en hongos, 10-VII-2005, J. Asiain y J. Márquez cols.” (52, CC-UAEH) . Same data, except: “camino a El Vergel, La Cascada, bosque de encino, en hongos, 9-VIII-2001, J. Asiain, S. Bautista y J. Márquez cols.” (1, MAAS) . “ Santiago Yosondua, La Cascada , bosque de encino, 1917 m, N16°50’49.6”, W97°34’47.5”, en Boletus sp. , 10-VI-2005, J. Márquez y J. Asiain cols” (6, CC-UAEH) . Veracruz: “Coscomatepec, Tecoac, bosque mesófilo de montaña, 1750 m, ex NTP-80 (calamar) # 754, 3-VI a 1-VII-1995, M. A. Pensado y Q. Santiago cols.” (1, MAAS; 2, QJSJ). Same data, except: “ 23-IX a 21-X-1995 ” (1, QJSJ) . Same data, except: “ 6-V a 3-VI-1995 ” (2, QJSJ) . Same data, except: “ 8-IV a 6-V-1995 ” (2, QJSJ) .

Figures

FIGURE 3. Dorsal view of males of: a) Belonuchus magnistylus (paratype), b) B. metafemoralis (paratype), c) B. oxyporimimus (paratype), d) B. pulcher (paratype), e) B. oxyporinus (holotype, NHM©), f) B. oxyporinus, g) B. rufisternus (holotype), h) B. singularis (holotype). Scale bars = 2.5 mm.

FIGURE 11. Mesoventrite of males of: a) Belonuchus cariniventris, b) B. oxyporinus, c) B. rufisternus, d) B. tepoztecus, e) B. bidens, f) B. jalappensis, g) B. longitarsus, h) B. ephippiatus, i) B. dichrous, j) B. flavipennis, k) B. platypterus, l) B. juanmorronei, m) B. iridescens. Red arrow: intercoxal process of the mesoventrite, blue arrow: transverse discal ridge, green arrow: longitudinal carina in anterior half.

FIGURE 12. Mesoventrite of males of: a) Belonuchus viridipennis, b) Belonuchus sp. Q, c) B. cyanipennis. Ventral view of the left femur of male anterior leg of: d) B. apiciventris, e) B. oxyporimimus, f) B. oxyporinus, g) B. tepoztecus, h) B. bidens, i) B. viridipennis. Ventral view of the left posterior leg of males of: j) B. julietitae, k) B. linuzensis (small specimen), l) B. linuzensis (large specimen), m) B. metafemoralis, n) B. oxyporimimus, o) B. oxyporinus. Red arrow: intercoxal process of the mesoventrite, blue arrow: transverse discal ridge.

FIGURE 15. Male pregenital sternite of: a) Belonuchus alternans, b) B. oxyporinus, c) B. tepoztecus, d) B. jalappensis, e) B. iridescens, f) B. platypterus, g) B. cyanipennis, h) B. apiciventris, i) B. linuzensis, j) B. metafemoralis, k) B. rufisternus, l) B. tenuistylus, m) B. bidens, n) B. pollens, o) B. longitarsus.

FIGURE 18. Male genital sternite of: a) Belonuchus altenans, b) B. apiciventris, c) B. cariniventris, d) B. colon, e) B. confusus, f) B. julietitae, g) B. magnistylus, h) B. linuzensis, i) B. metafemoralis, j) B. oxyporimimus, k) B. oxyporinus, l) B. pulcher, m) B. rufisternus, n) B. singularis, o) B. tenuistylus. Scale bars = 0.5 mm.

FIGURE 22. Ventral (left) and lateral (right) view of the aedeagus of: a) Belonuchus oxyporimimus, b) B. oxyporinus, c) B. pulcher, d) B. rufisternus, e) B. singularis, f) B. tenuistylus, g) B. tepoztecus (at center detail of the paramere), h) B. trochanterinus, i) B. zunilensis. Scale bar = 0.5 mm (all figures).

FIGURE 27. Geographical distribution in Mexico of: a) Belonuchus erichsoni and B. oxyporinus; b) B. longitarsus, B. metafemoralis, B. mixtecus, B. optatus and B. rufiventris.