Laccomimus amazonas, 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 : 315-316

Laccomimus amazonas sp. n.

( Figs 10 ; 24–27; 38; 47–48; 62; 75; 88; 110; 124; 137)

Type locality. Venezuela, Amazonas State, Communidad caño Gato on Río Sipapo, 4°58.838'N, 67°44.341'W, 95 m.

Type material. Holotype male ( MIZA), dissected by us; genitalia mounted in DMHF on plastic label pinned under the holotype “ Venezuela, Amazonas State, 4°58.838'N, 67°44.341'W, 95 m, Comunidad caño Gato on Rio Sipapo, 16.I.2009, leg. Short, Miller, Camacho, Joly & García, VZ09-0116- 01X, along stream” [printed], “SM0843379 KUNHM-ENT ” [printed, together with barcode], “ HOLOTYPE Laccomimus amazonas Toledo & Michat” [red, rectangular, printed label].

Paratypes (33 exs, all bearing red, printed label “ PARATYPE Laccomimus amazonas Toledo & Michat”): Venezuela: same data as holotype (30 exs VAIP, MTP, MCMC, NMW); “ Amazonas State, 4°55.849'N, 67°44.645'W, 87 m, stream along Rio Sipapo, 16.I.2009, leg Short, Garcia, Camacho, Miller & Joly, VZ09-0116- 02X, stream habitats” (2 exs VAIP); “ Amazonas State, 5°20.497'N, 67°45.358'W, 72 m, ca. 12 km N Samariapo, small stream at rd. x-ing, 6.I.2006, AS-06-013, leg. A.E.Z. Short” (1 ex. VAIP). Each specimen bearing second VAIP label with its own barcode and catalogue number.

Diagnosis. Easily recognised by the following combination of characters: lobes of metacoxal processes ending in long sharp spine in both sexes; elytra dark with distinct pale markings; male with very large stalked suction palettes and outer claw of forelegs scimitar-shaped. Aedeagal features distinctive, median lobe expanded on apical fourth ( Fig. 88 a) and left paramere triangular, gradually tapering apically ( Fig. 88 b).

Description. Habitus ( Fig. 62 ). TL: 2.2–2.4 mm; MW: 1.15–1.2 mm; (holotype: TL: 2.3 mm; MW: 1.15 mm); A-TL: 2.4 mm; A-MW: 1.2 mm (NUM: 16 exs); drop-shaped, strongly but regularly narrowed posteriorly. Smooth; elytra with faint silky sheen.

Colour. Head testaceous, often darkened behind eyes. Pronotum testaceous, with darker transverse marking along posterior margin, normally divided into two parts. Elytra chestnut-brown; each elytron with three distinct yellow markings: transverse, subbasal band reaching lateral side; submedial faded spot close to lateral side; subapical marking not reaching apex. Underside reddish-yellow. Antennae and mouthparts testaceous. Legs reddish-yellow.

Structures and sculpture. Head shiny, with faint microreticulation and scattered fine punctures on disc.

Pronotum smooth, sculpture as on head, with faint silky sheen. Elytra elongate, with subapical sinuation poorly developed and elytral apex narrow, almost acute; surface smooth, with faint silky sheen; fine and scattered punctures are visible in most specimens but no grooves occur, in contrast to preceding species. Underside shiny, lacking silky sheen. Prosternal process broad, slightly elevated especially close to rounded tip ( Fig. 24–27 ). Lobes of metacoxal processes ending in long sharp spine in both sexes ( Fig. 38 ).

Male. Last abdominal ventrite tectiform with lateral sides almost rectilinear. Stalked suction palettes on pro- and mesotarsi very broad, broader than in any other Laccomimus species ( Figs 47–48 ; compare with Fig. 44 and Figs 49 ; 51). Outer claw of forelegs scimitar-shaped ( Fig. 75 ). Median lobe of aedeagus, in left lateral view ( Fig. 88 a), resembling that of L. variegatus , with leaf-like expanded apical fourth but visibly narrower, especially before apical expansion. In dorsal view ( Fig. 110 ) slightly turning to right, gradually tapering from base to apex, with nipple-like tip; dorsal lamina sinuate and ejaculator groove narrower on basal half and wider near apex. Left paramere distinctive ( Fig. 88 b): triangular, shorter than in any other Laccomimus species, and more gradually tapering apically.

Female. Last abdominal ventrite elongate, with fore margin broadly rounded. Lateral tergites thin and partly membranous. Gonocoxal blade with single medial denticle; ramus with large and spaced dentation; first tooth, following apical hook, very small with respect to second tooth.

Distribution. Venezuela, Amazonas State ( Fig. 124 ).

Habitat. Collected in running waters ( Fig. 137 ).

Etymology. The specific epithet relates to type locality. It is treated as a noun in the nominative singular.

Remarks. See under L. variegatus .

Figures

FIGURES 8 – 13. SEMs of Laccomimus species, ventral view: 8) L. distinctus (male); 9) L. malkini (female); 10) L. amazonas (male); 11) L. alvarengi (female); 12) L. bordoni (male); 13) L. bolivari (female).

FIGURES 88 – 90. Male genitalia in Laccomimus species, left lateral view: 88) L. amazonas, a) median lobe, b) left paramere, c) right paramere; 89) L. improvidus, a) median lobe, b) magnification of apex of median lobe, c) left paramere; 90) L. youngi, a) median lobe (holotype), b) magnification of apex of median lobe (holotype), c) magnification of apex of median lobe (different specimen from type locality), d) left paramere (holotype), e) left paramere (different specimen from type locality).

FIGURES 59 – 66. Subschematic body shape and colour patterns in Laccomimus species: 59) L. distinctus; 60) L. malkini, a) typical specimen from Colombia, b) specimen from Piracicaba, Brazil; 61) L. variegatus (Perú); 62) L. amazonas; 63) L. pumilio (Florida, USA); 64) L. alvarengi, a – b) variation in colouration patterns; 65) L. bordoni; 66) L. spangleri.

FIGURES 20 – 25. SEMs of head, prosternum and prosternal process in Laccomimus species: 20) L. distinctus (male), ventral view, 21) idem, at higher magnification; 22) idem, oblique lateral view; 23) L. malkini (female) ventral view; 24) L. amazonas (male), ventral view (arrow indicates protruding prosternum); 25) idem, at higher magnification.

FIGURES 26 – 31. SEMs of head, prosternum and prosternal process in Laccomimus species: 26) L. amazonas (male), oblique lateral view; 27) idem, at higher magnification; 28) L. alvarengi (female) ventral view; 29) L. bordoni (female), ventral view; 30) idem, oblique lateral view; 31) idem, at higher magnification.

FIGURES 38 – 43. SEMs of Laccomimus species, ventral view. 38 – 41) metacoxal processes: 38) L. amazonas (male); 39) L. alvarengi (female); 40) L. bordoni (female); 41) L. bolivari (female); 42 – 43) abdomen on L. bordoni, showing sexual difference in last ventrite: 42) male (arrow indicates slightly sinuate caudal margins); 43) female.

FIGURES 44 – 51. SEMs of left protarsus in Laccomimus species (males): 44) L. distinctus, general view; 45) idem, detail at higher magnification of last protarsal segment and claws; 46) idem, detail at higher magnification of stalked suction palettes; 47) L. amazonas, general view; 48) idem, detail at higher magnification of stalked suction palettes; 49) L. bordoni, general view; 50) idem, detail at higher magnification of last protarsal segment and claws; 51) idem, detail at higher magnification of stalked suction palettes.

FIGURES 67 – 83. Prosternal process and claws in Laccomimus species. 67 – 69) P rosternal process: 67) L. pumilio (Florida, USA); 68) L. pumilio (Cuba); 69) L. alvarengi (Perú). 70 – 83) M ale left protarsal claws: 70) L. bordoni (Paraguay); 71) L. malkini (Madre de Dios, Perú); 72) L. spangleri (holotype); 73) L. distinctus (holotype); 74) L. bolivari (Trinidad); 75) L. amazonas (holotype); 76) L. variegatus (Colonia Calleria, Perú); 77) L. alvarengi (holotype); 78) L. alvarengi (Loreto, Perú); 79) L. alvarengi (Guayaramerin, Bolivia); 80) L. alvarengi (Esmeraldas, Ecuador); 81) L. alvarengi (Albrook, Panamá); 82) L. pumilio (Cayo District, Belize); 83) L. pumilio (Cayamas, Cuba).

FIGURES 107 – 115. Median lobe of aedeagus in Laccomimus species, dorsal view: 107) L. distinctus; 108) L. malkini; 109) L. variegatus; 110) L. amazonas; 111) L. alvarengi; 112) L. improvidus; 113) L. bordoni; 114) L. spangleri; 115) L. bolivari.

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.

FIGURES 136 – 138. Habitats of Laccomimus species: 136) L. bolivari, small streamlet S of Comunidad Porvenir, Amazonas State, Venezuela (photo A. E. Z. Short); 137) L. amazonas, stream along Río Sipapo, Amazonas State, Venezuela (photo A. E. Z. Short); 138) L. distinctus, marshy area and pool by road ca. 10 km E Mantecal, Apure State, Venezuela (photo A. E. Z. Short).