Laccomimus variegatus, 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: 313-314

publication ID

http://dx.doi.org/10.11646/zootaxa.3990.3.1

publication LSID

lsid:zoobank.org:pub:378C0359-E0E4-4CCC-821D-649144E37A63

persistent identifier

http://treatment.plazi.org/id/03EE87FE-FFFF-FFF9-91A6-FA27FB09A636

treatment provided by

Plazi

scientific name

Laccomimus variegatus
status

sp. n.

Laccomimus variegatus  sp. n.

( Figs 61View FIGURES 59 – 66; 76; 86; 109; 119; 124)

Type locality. Perú, Colonia Calleria, Río Calleria, 15 km E Ecayali.

Type material. Holotype male ( USNM): dissected by us; median lobe of aedeagus and parameres included in DMHF on plastic label pinned under the holotype “ Peru, Colonia Calleria, 15 [km?] E Ecayali, muddy R. Shore, ix. 10 –25.61, B. Malkin # 14 ” [printed white label; number “ 14 ” hw], “ HOLOTYPE Laccomimus variegatus  Toledo & Michat” [red, rectangular, printed label].

Paratypes (24 exs, all bearing red, printed label “ PARATYPE Laccomimus variegatus  Toledo & Michat”): Perú: same data as holotype (9 exs USNM); idem, exception made for “ ix. 10 –30.61” plus “# 1 ” (1 ex. USNM); idem, exception made for “# 16 ” (1 ex. USNM); “Loreto, 80 km NE Iquitos, Explorama Lodge, 1 km up Rio Yanamono from Amazon River, 1–5.IX. 1992, P. Skelley, at light / coll. Hendrich Berlin" (1 ex. ZSM). Bolivia: “Guayaramerin, Beni, river bank, Balogh, Mahunka, Zicsi”, “No. 428, beaten from vegetation, 2.Xii. 1966 ” (1 ex. HNMB); “Beni, 40 km E San Borja, Estacion Biologica Beni, Estancia El Porvenir, 6–8.IX. 1987, W.E. Steiner”, “At black light: open grass savanna and marsh” (8 exs USNM); “Beni, 40 km E San Borja, Estacion Biologica Beni, Palm Camp at Rio Curitaba, 13.IX. 1987 / At black light, mud flat in small open area of inondation forest, W- E. Steiner" (3 exs –two of which unlabelled – USNM).

Diagnosis. Unmistakable species based on the peculiar elytral colouration, with vermiculation of irregular obscure markings and pale spots ( Fig. 61View FIGURES 59 – 66), unique within Laccomimus  . Lobes of metacoxal processes ending in long spine in both sexes. Aedeagal features distinctive, median lobe expanded on apical fourth ( Fig. 86View FIGURES 84 – 87 a) and left paramere strongly narrowed on distal half ( Fig. 86View FIGURES 84 – 87 b).

Description. Habitus ( Fig. 61View FIGURES 59 – 66). TL: 2.2–2.4 mm; MW: 1.15–1.25 mm; (holotype: TL: 2.3 mm; MW: 1.2 mm); A-TL: 2.3 mm; A-MW: 1.1 mm (NUM: 16 exs); elongate, drop-shaped, strongly narrowed posteriorly. Smooth; dorsal surface with faint silky sheen.

Colour. Head testaceous, slightly darker between eyes in some specimens; pronotum testaceous with darker band along fore margin and obscure darker area close to hind margin. Elytra testaceous to reddish-brown with characteristic vermiculation of darker, obscure and irregular markings together with tiny, rounded, pale spots; these markings are concentrated mostly on disc and along lateral sides of elytra, giving illusion of very irregular, longitudinal patterns. Underside reddish-yellow to brown, paler on prosternum. Antennae and mouthparts testaceous. Legs testaceous.

Structures and sculpture. Head smooth, shiny, with fine and hard to recognise microreticulation. Pronotum smooth, with few shallow and fine punctures scattered on disc and, more numerous along inner and fore margins; microreticulation as on head; iridescence absent. Elytra elongate with pronounced subapical sinuation; surface shiny, faintly iridescent; microreticulation fine, poorly impressed; small, shallow, irregular grooves visible together with fine scattered punctures. Underside shiny, with hardly visible silky sheen. Prosternal process broad, slightly elevated, obtuse at tip. Lobes of metacoxal processes ending in long sharp spine in both sexes.

Male. Last abdominal ventrite tectiform, lateral sides almost rectilinear. Outer claw of forelegs scimitar-shaped ( Fig. 76View FIGURES 67 – 83). Median lobe of aedeagus, in left lateral view ( Fig. 86View FIGURES 84 – 87 a), widely arched, slender but robust, expanded on apical fourth, then narrowed into subtruncate tip. In dorsal view ( Fig. 109View FIGURES 107 – 115), sinuate on both sides, with visible constriction on distal third of left side; apex with narrow tip turned to left; ejaculator groove almost uniformly wide up to apex. Left paramere ( Fig. 86View FIGURES 84 – 87 b) regularly rounded along ventral side, strongly narrowed beyond basal half on dorsal side.

Female. Not duller than male. Last abdominal ventrite elongate, with fore margin broadly rounded. Lateral tergites thin, partly membranous. Gonocoxal blade ( Fig. 119View FIGURES 116 – 121 a) with single medial denticle; ramus ( Fig. 119View FIGURES 116 – 121 b) with large and spaced dentation; first tooth, following apical hook, as developed as second tooth.

Distribution. Bolivia, Perú ( Fig. 124View FIGURES 122 – 125).

Etymology. The specific epithet is an adjective in the nominative singular and refers to the distinctive elytral colouration, unique within this genus.

Notes on variability. All but one specimens from Bolivia (all immature) bear obscure markings on the elytra, very difficult to see, colouration appearing uniform. This might also depend on the way the beetles have been killed and preserved.

Remarks. This species is very close to L. amazonas  and L. spinosus  , but readily recognisable by the peculiar elytral colouration. These three species form a distinct group within Laccomimus  , characterised by the following combination of peculiar characters: prosternum protruding anteriorly, almost bulbous ( Figs 24–26View FIGURES 20 – 25View FIGURES 26 – 31); prosternal process very broad and short, saddle shaped in lateral view, barely reaching metaventrite and positioned below its level ( Figs 24–26View FIGURES 20 – 25View FIGURES 26 – 31); lobes of metacoxal processes ending in long sharp spine in both sexes ( Fig. 38View FIGURES 38 – 43).

USNM

Smithsonian Institution, National Museum of Natural History

ZSM

Bavarian State Collection of Zoology