Laccomimus spinosus, Toledo, Mario & Michat, Mariano C., 2015

Toledo, Mario & Michat, Mariano C., 2015, Description of Laccomimus gen. n. and eleven new species from the Neotropical region (Coleoptera, Dytiscidae, Laccophilinae), Zootaxa 3990 (3), pp. 301-354 : 314-315

Laccomimus spinosus sp. n.

( Figs 87 ; 124)

Type locality. Brazil, Matto Grosso, Jacaré, Xingu National Park.

Type material. Holotype male ( USNM), dissected by us; genitalia mounted in DMHF on plastic label pinned under the holotype “ Brazil, Matto Grosso, Jacaré, P.N. Xingu, XI.1961, Alvarenga e [sic!] Werner leg.” [printed], “ HOLOTYPE Laccomimus spinosus Toledo & Michat” [red, rectangular, printed label].

Diagnosis. Easily recognised by the following combination of characters: lobes of metacoxal processes ending in long sharp spine in both sexes; male with outer claw of forelegs scimitar-shaped. Aedeagal features distinctive, median lobe lacking apical expansion but with faint constriction at about mid length ( Fig. 87 a).

Description. (based on holotype). TL: 2.3 mm; MW: 1.2 mm; similar to L. variegatus except body somewhat broader and shorter, strongly but regularly narrowed posteriorly, lacking elytral patterns. Elytral surface with visible silky sheen.

Colour (it is an old specimen and colouration might be altered). Head uniformly testaceous; pronotum testaceous with darker band along posterior margin. Elytra almost uniformly reddish-brown, with darker parasutural line. Underside uniformly reddish-brown. Antennae and mouthparts testaceous. Legs testaceous.

Structures and sculpture. Head smooth, shiny, with hardly visible microreticulation and scattered punctures of different size. Pronotum with lateral sides widely rounded toward anterior angles; surface as on head, with a faint silky sheen and hardly visible microreticulation. Elytra shorter than in preceding species; subapical sinuation visible although poorly developed; elytral apex narrow, almost acute; surface with faint silky sheen; irregular shallow grooves and scattered punctures visible as in L. variegatus . Underside with intense iridescence. Prosternal process as in L. variegatus but centrally quite convex, rounded at tip. Lobes of metacoxal processes ending in long sharp spine.

Male. Last abdominal ventrite tectiform with lateral sides almost straight. Outer claw of forelegs scimitarshaped. Median lobe of aedeagus, in left lateral view ( Fig. 87 a), regularly curved, narrowed to apex, lacking expansions but with faint constriction dividing basal and apical halves. Left paramere ( Fig. 87 b) similar to that of L. variegatus but apical half thicker and less elongate.

Female. Unknown.

Distribution. Brazil. Known only from the type locality ( Fig. 124 ).

Etymology. The specific epithet is an adjective in the nominative singular and alludes to the acuminate spine on each lobe of metacoxal processes, characteristic of this species and those closely related.

Remarks. See under L. variegatus .

Figures

FIGURES 84 – 87. Male genitalia in Laccomimus species, left lateral view: 84) L. distinctus, a) median lobe, b) left paramere, c) right paramere; 85) L. malkini (Loreto, Perú), a) median lobe, b) magnification of apex of median lobe, c) left paramere, d) right paramere, e) magnification of apex of median lobe (specimen from Piracicaba, Brazil); 86) L. variegatus, a) median lobe, b) left paramere, c) right paramere; 87) L. spinosus, a) median lobe, b) left paramere.

FIGURES 122 – 125. Distribution maps of Laccomimus species: 122) L. distinctus; 123) L. malkini; 124) L. variegatus (open circles), L. spinosus (single pentagon in Brazil), L. amazonas (single star in Venezuela); 125) L. alvarengi in South America.