Mentophilonthus ochrigonalis ( Tottenham, 1962 ) Hromádka, 2009

Hromádka, Lubomír, 2009, Revision of the Afrotropical species of the genus Mentophilonthus (Coleoptera: Staphylinidae: Philonthina), Acta Entomologica Musei Nationalis Pragae (suppl.) 49 (1), pp. 119-160 : 140-142

Mentophilonthus ochrigonalis ( Tottenham, 1962) comb. nov.

( Figs. 64–68 )

Philonthus (Philonthus) ochrigonalis Tottenham, 1962: 156 .

Mentophilonthus bangoranensis Levasseur, 1980: 351 syn. nov.

Type locality. Southern Sudan: 18 miles E of Yirol.

Type material examined. Philonthus ochrigonalis : HOLOTYPE: ♁, ‘S. Sudan:18mls E.of Yirol , 4.vi.54, elephant dung // Holotype, Philonthus ochrigonalis Tottenham [white oblong label, handwritten]’ ( BMNH) . PARATYPES: ♀, ‘ Juin Rives du Moyen Chari, Amont des Niellims , Mission Chari-Tchad, Dr. J. Decorse, 1904 [white oblong handwritten paratype label]’ ( BMNH) ; ♁ ♀,‘S. Sudan: 18 mls. E. of Yirol , 4.vi.1954, C.E. Tottenham, M. Cameron Bequest B.M. 1955–147, elephant dung’ [white oblong, handwritten paratype label] ( BMNH) .

Note. I did not study the type material of M. bangoranensis . The original description of this species by LEVASSEUR (1980) is rather incomplete and it is therefore difficult to decide whether P. bangoranensis is really identical with P. ochrigonalis in all important characters. However, two characters mentioned in the description (proportion and shape of the aedeagus) support the synonymy proposed above.

Redescription. Body length: 9.6–10.0 mm, length of fore body (to end of elytra) 4.6– 4.9 mm.

Colouration. Head black, antennal sockets and clypeus along anterior margin very narrowly reddish-yellow, labrum brown-yellow, mandibles dark brown, pronotum, elytra and abdomen black-brown, epipleura and posterior angles of elytra white-yellow, elytral suture and sides of scutellum narrowly brown-yellow, maxillary and labial palpi dark brown, antennae brownblack, ventral side of antennomere 1 extensivelly yellowish, dorsal side brown-black, legs brown-yellow, inner side of all tarsi infuscate.

Head as long as wide. Posterior angles markedly rounded, each with two long black bristles. Eyes flat, much longer than temples (ratio 12: 7), posterior margin of eyes with three setiferous punctures arranged into transverse row. Dorsal surface with microsculpture consisting of transverse and oblique waves.

Antennae reaching midlength of pronotum when reclined. Antennomere 1 somewhat longer than antennomeres 2–3 combined, antennomere 11 as long as antennomeres 9–10 combined. Relative lengths of antennomeres: 1 = 10; 2 = 4.5; 3 = 5; 4–8 = 3; 9–10 = 2.5; 11 = 5.

Pronotum hardly longer than wide (ratio 40: 39), slightly narrowed anteriad, posterior angles entirely. Each dorsal row and each sublateral row with two punctures. Microsculpture similar to that on head.

Scutellum moderately densely and finely punctate, punctures slightly smaller than eyefacets. Surface without microsculpture; setation dark, relatively long.

Elytra combined wider than long (ratio 51: 44), slightly widened posteriad, hardly wider than pronotum basally. Punctation fine and dense, punctures as large as eye-facets, separated by a puncture diameter in transverse direction. Longitudinal row of four coarse punctures situated at midwidth of each elytron. Surface without microsculpture; setation brown-yellow.

Legs. Metatibia slightly shorter than metatarsus (ratio 26: 28). Metatarsomere 1 as long as metatarsomeres 2–3 combined, metatarsomere 5 much shorter than metatarsomere 1. Relative lengths of metatarsomeres: 1 = 9; 2 = 5; 3 = 4; 4 = 3; 5 = 6.5. All tibiae with several strong dark bristles.

Abdomen parallel–sided anteriorly, hardly narrowed posteriad from visible tergite III, first four visible tergites with two basal lines, elevated area between basal lines with scattered fine punctures. Punctation of visible tergites somewhat sparser and coarser than that on elytra, punctures slightly larger than eyefacets. Surface between punctures without microsculpture, shiny.

Male. Protarsomeres 1–3 strongly dilated, sub-bilobed, densely covered with modified pale setae ventrally, protarsomere 4 much narrower than preceding ones. Sternite IX ( Fig. 68 ), aedeagus ( Figs. 64–67 ).

Female. Protarsomeres 1–3 much less dilated than those in male, protarsomere 4 very small, only first three protarsomeres bearing modified pale setae ventrally.

Differential diagnosis. Mentophilonthus ochrigonalis is similar to M. centrafricanus , from which it may be distinguished by the wider head and denser punctation of the abdomen. It may be distinguished from M. dilutior by the narrower head and sparser punctation of the abdomen, from M. curiosus by the coarser punctation of the abdomen and paler posterior margin of the elytra. It differs from all above species by the shape of the aedeagus.

Bionomics. One of the specimens examined was found in elephant dung.

Distribution. Sudan (this paper); Central African Republic ( HERMAN 2001).

Figures

Figs. 56–68. 56–63 – Mentophilonthus mongedensis (Bernhauer, 1928): 56–59 – aedeagus (56 – ventral view, 57 – lateral view, 58 – ventral view, without paramere, 59 – underside of paramere with sensory peg setae); 60 – apical portion of male sternite VIII, ventral view; 61 – male sternite IX, ventral view; 62 – female tergite X, dorsal view; 63 – gonocoxites of female genital segment. 64–68 – Mentophilonthus ochrigonalis (Tottenham, 1962). 64–67 – aedeagus (64 – ventral view, 65 – ventral view, without paramere, 66 – lateral view, 67 – underside of paramere with sensory peg setae); 68 – male sternite IX, ventral view.