Osorius costaricensis BERNHAUER

Irmler, Ulrich, 2010, The Neotropical species of the genus Osorius G - M, 1829 with remarks to the Neotropical Osoriid complex (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 60 (2), pp. 363-426: 383-384

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http://doi.org/ 10.21248/contrib.entomol.60.2.363-426



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Osorius costaricensis BERNHAUER


Osorius costaricensis BERNHAUER   ,, 1942: 7 (Figs 12 a-c)

Type material examined:

Costa Rica: Reventazon (83°28' W, 10°10' N), 2 males without further data (syntypes, FMNH) GoogleMaps   .

Additional material examined:

Guatemala: La Union (89°17' W, 14°58' N), 3.5 km SE, under bark, 6 specimens, 25.6.1993, leg. J.S. Ashe ( KU, UIC) GoogleMaps   ; Honduras: Franzisco Morazan , 7.6 km N Guaimaca (86°49' W, 14°36' N), under bark, 820 m elevation, 3 specimens, 26.6.1994, J.S. Ashe ( KU) GoogleMaps   ; Nicaragua: Matagalpa (85°54' W, 12°54' N), 10 km NW, Selva Negra , leaf litter at stream, 1 specimen, 22.5.2002, leg. L. Herman ( AMNH) GoogleMaps   ; Isla de Ometepec (85°34.55 W, 11°24.71 N), Volcan Maderas , ex troncos podridos, 746 m elevation, 3 specimens, 30.1.2000, leg. J. Marquez ( UNAM) GoogleMaps   ; Granada (85°57 W, 11°55 N), Res. Nat. Volcan Mombacho , under bark, 375 m elevation, 1 specimen, 2.2.2000, leg. J. Marquez ( UNAM) GoogleMaps   ; Costa Rica: Heredia: La Selva (84°01' W, 10°26' N), 3.2 km SE Puerto Viejo , flight intercept trap, 3 specimens, 21.3.1992, 1 specimen, 17.2.1992, 1 specimen, 14.2.1992, leg. W. Bell ( KU) GoogleMaps   ; Alajuela: Rio Penas Blancas , under bark, 6 specimens, 18.5.1989, leg. J.S Ashe ( KU, UIC)   ; Monteverde , Malaise trap, 1 specimen, 9.5.1989, leg. J.S. Ashe ( KU)   ; Santa Elena Puntarenas (82°47.85 W, 8°55.26 N), Area de proteccion, Sierra de Talamanca, Selva alta subperenifolia, troncos con hongos fumigados, 1535 m elevation, 1 specimen, 26.2.2000, leg. J. Marquez ( UNAM) GoogleMaps   ; Panama: Bocas del Toro, 7 km N Boquete, La Culebra trail, 5 specimens, 15.7.1995, leg. A.R. Gillogly ( KU, UIC)   .


O. costaricensiscostaricensis   is one of the smallest species of Neotropical Osorius   . In this respect it can be confused with O. dentatus   , O. paganus   and O. sublaevis   . In contrast to O. dentatus   , the surface of pronotum in O. costaricensiscostaricensis   is matte at the distinct microsculpture, whereas surface is shiny in O. dentatus   . In contrast to O. sublaevis   , punctation in O. coastaricensiscoastaricensis   is sparser and finer. In particular, it resembles O. paganuspaganus   in size, microsculpture and punctation. O. costaricensis   is more slender in the overall feature than O. paganus   , and postocular striae are present that are absent in O. paganus   . Moreover, the aedeagus in O. paganuspaganus   is extremely long and acute, whereas it is shorter and with obtuse apex in O. costaricensis   .


Length: 6.5 – 7.8 mm. Colour: black, legs and antennae brown.

Head :: 0.9 – 1.2 mm long, 1.2 – 1.5 mm wide; eyes not prominent, front edge of clypeus with broad, obtuse lateral prominence divided by a gap with a setiferous puncture; punctation moderately deep and dense, distance between punctures on average as wide as or 1.5 times wider than diameter of punctures; with sparse micro-punctation, microsculpture weak and isodiametric; surface shiny; on posterior portion of clypeus with two granular setiferous punctures on each side; three supraocular setiferous punctures and a pair of postocular setiferous punctures; with few short, postocular striae.

Antennae with more or less circular 2 nd antennomere; 3 rd conical antennomere only slightly longer than 2 nd; subsequent antennomeres increasing in width; 4 th antennomere quadrate; 10 th antennomere wider than long.

Pronotum: 1.2 – 1.4 mm long, 1.3 – 1.7 mm wide; widest at anterior angles; lateral margin small at anterior angles; distinctly widened in posterior half; punctation sparser and finer than on head; distance between punctures at least twice as long as diameter of punctures; a small midline without punctures; a transverse row of five setiferous punctures along front edge and two pairs of setiferous punctures in posterior half; one pair laterad in posterior third and one pair near midline in front of posterior edge; with distinct isodiametric microsculpture; surface matte.

Elytra: 1.4 – 1.8 mm long, 1.3 – 1.6 mm wide; with deep coriaceous ground sculpture; punctation nearly invisible, surface shiny.

Aedeagus broad, nearly circular; with long apex in relation to short basal part; apex curved.


Field Museum of Natural History


Biodiversity Institute, University of Kansas


American Museum of Natural History


Universidad Nacional Autonoma de Mexico