Hemiosus selva Short

Short, Andrew Edward Z. & Torres, Phillip J., 2006, Review of the Hemiosus Sharp and Derallus Sharp of North America, Central America, and the Caribbean (Coleoptera: Hydrophilidae: Berosini), Zootaxa 1369, pp. 1-17 : 6-7

Hemiosus selva Short , sp. n.

( Figs. 3, 5 )

Type locality. COSTA RICA: Heredia Provice, La Selva Biological Station, near Puerto Viejo.

Type Material. Holotype (male): “ COSTA RICA: Heredia Province/ nr. Puerto Viejo, La Selva Bio. St./ 179 ft., Station Grounds/ 19.viii. 2003, C.R. Bartlett, leg.”, “ HOLOTYPE / Hemiosus / selva / des. A.E.Z. Short” ( INBio). Paratypes (129): COSTA RICA: Cartago: Turrialba, 13–17.iii. 1965, S.S. & W.D. Duckworth leg. (18: USNM); same data but 22–28.ii. 1965 (22: USNM); Turrialba, 15.vii. 1965, P.J. Spangler leg. (9: USNM); Turrialba, 650 m, 4–13.viii. 1970, HG-vapor light trap, J. & M. Sedlacek leg. (29: AEZS, BPBM, NMW); Guanacaste: Las Cañas, 13.vii. 1965, P.J. Spangler leg. (1: USNM); Heredia: same data as holotype (1: AEZS); La Selva Biological Station nr. Puerto Viejo, HG Vapor light, (14–15). i. 2005, A.E.Z. Short leg., AS-05- 153 (1: AEZS); same data but 18–19.viii. 2003 (5: AEZS); same data but (22–24). i. 2000 (11: AEZS, INBio, USNM); Limón: La Lola nr. Matina, 11.iii. 1965, S.S. & W.D. Duckworth leg. (8: USNM); Hitoy Cerere Biological Reserve, Hitoy Cerere Station, 160 m, 17.i. 2000, W. Arana leg. (1: INBio), same locality but 200 m, 10.ii. 2000 (1: INBio); Hitoy Cerere Biological Reserve, “send. a catarata” [trail to waterfall], 100–200 m, 26.viii. 2002, light trap, W. Arana leg. (1: INBio); same data but 11.xi. 1999 (1: INBio); Guapiles, Santa Clara, 24.iii. 1935 (1: USNM); Hamburg Farm, Reventezon, 27.vi. 1929, F. Nevermann leg. (7: USNM); same data but 26.ii. 1938 (1: USNM); same data but 6.i. 1933, (1: USNM).

Differential Diagnosis. Total length 2.8 –3.0 mm. This species can be distinguished from the remaining two mesoamerican species by the shape of the black iridescent spot on the pronotum ( Fig. 3 ), which does not reach the lateral margins but narrowly reaches the medial anterior margin; and by the strongly acuminate median lobe of the aedeagus.

Description. Coloration. Head entirely iridescent black. Maxillary palps largely yellow with tip of apical segment dark brown. Pronotum largely iridescent black centrally and reaching posterior margin in medial half and anterior margin in medial fifth to sixth ( Fig. 3 ); remainder of pronotal margins light brown to yellow. Elytra largely light brown to yellow with rows of serial punctures medium to dark brown. Dark brown maculae are present at posterior end of scutellary stria along elytral suture and medially on each elytron in interstriae 7 and 8. Elytral color patterns exhibit moderate intraspecific variation, with some individuals lacking elytral maculae. Head. Ground punctation on head dense and moderately coarse, slightly less coarse than punctation on pronotum. Maxillary palps slightly longer than anterior margin of clypeus. Thorax. Ground punctation on pronotum very coarse, uneven. Lateral margins of pronotum finely to moderately crenulate, often bearing long setae. Scutellum with coarse punctures. Median process of mesoventrite strongly elevated in anterior two-fifths, with posterior half only moderately elevated. Elytra with interstrial punctures coarse and distinct medially, subequal to slightly smaller than serial punctures, and becoming finer and nearly obsolete in lateral interstriae. Protarsi of males with segments 2–3 slightly enlarged and with longer ventral setae. Abdomen. First abdominal ventrite with median carina that is narrow and strongly raised anteriorly, gradually becoming wider and lower posteriorly. Abdominal ventrites 2–4 with trace of broad, low median carina in anterior half. Emargination of fifth ventrite with single acute projection medially. All ventrites very finely crenulate on lateral margins. Aedeagus ( Fig. 5 ) with median lobe strongly pointed apically, almost reaching the same level as apices of parameres. Parameres moderately narrowed apically to more or less acute apices, but not as acute as median lobe. Basal piece strongly asymmetrical in proximal half.

Etymology. This species is named after “ la selva ”, the Spanish word for “jungle”. The species name is to be considered a noun in apposition.

Distribution. Costa Rica, with all but one locality (i.e. Las Cañas in Guanacaste) on the Atlantic side of the continental divide.

Remarks. Most known specimens were collected at lights. At least one was collected in an “aquatic” situation.

Figures

FIGURES 3 – 5. Details of Hemiosus selva Short, sp. n. (3, 5) and H. exilis (LeConte) (4). 3 – 4: pronotal coloration, scale bar 0.18 mm; 5: aedeagus, scale bar 0.2 mm.