Laccomimus bordoni, 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 : 320-322

Laccomimus bordoni sp. n.

( Figs 4 ; 6, 7; 12; 16–19; 29–31; 40; 42–43; 49–56; 65; 70; 103; 113; 120; 126; 128; 130)

Type locality. Venezuela, Higuerote.

Type material. Holotype male ( USNM): dissected probably by Young; genitalia and last two abdominal ventrites glued on separate label under the holotype “ Venezuela ”, “Higuerote m. 5, (Barlovento - Edo. Miranda)”, “4 febr. 1962, leg. Bordon” [three rectangular, white labels, printed], “ Holotype Laccomimus bordoni Young 69” [red, handwritten by Young], “ HOLOTYPE Laccomimus bordoni Toledo & Michat” [red, rectangular, printed label].

Paratypes (218 exs, all bearing red, printed label “ PARATYPE Laccomimus bordoni Toledo & Michat”): Venezuela: same data as holotype, except for white label, instead of red, handwritten by Young “ Laccomimus bordoni Young '69” (12 exs USNM); “Bolivar, El Dorado (65 km S), 1.XII.1982, John L. Hellman” (4 exs USNM). Argentina: “Prov. Misiones, Yacutinga res., 4–3.II.2006, light trap, leg. M.C. Michat” (1 ex. MCMC); “Prov. Jujuy, Calilegua N.P., lagoon, 16.XII.2003, leg. M.C. Michat” (1 ex. MCMC); idem “ 18.IX.2005 ” (2 exs MCMC); “Prov. Chaco, 97 km NW of Resistencia, 10 km W of Capitán Solari, 26°48'32"S, 59°36'29"W, 3–7.II.2004 [collector not given]” (1 ex. NHMP). Bolivia: “Guayaramerin, Beni, river bank, Soil Zoological Exp., Balogh, Mahunka, Zicsi”, “No. 428, beaten from vegetation, 2.XII.1966 ” (5 exs HNMB); “Guayaramerin, Beni, outskirts of town, Soil Zoological Exp., Balogh, Mahunka, Zicsi”, “No. 391, lamping, 22.XI.1966 ” (2 exs HNMB); idem “No. 424, lamping., 1.XII.1966 ” (2 exs HNMB); “Santa Cruz, San Antonio, Rio de Parapeti, Rio Parapeti, 15– 19. VII.1964, B.M. Malkin” (1 ex. USNM); “Santa Cruz, Sara, 2 km NW Santa Rosa, 21.II.1969, BLT A. Martinez & R.E. Woodruff” (3 exs USNM); idem, “ 3 km S Santa Rosa, 22.II.1969 ” (10 exs USNM); “Santa Cruz, 60 mi. N Santa Cruz, Saavedra Expl. Sta., 27–30.XII.1959, Robert Cumming, collected at black light” (1 ex. USNM). Brazil: “Mato Grosso, Cuiabà (Cuyabà), 30.III.1972, BLT W.H. Whitcomb” (1ex. USNM); idem “ 11.IV.1972 ” (1 ex. USNM). Dominican Republic: “Sanchez, VII.1938, Darlington” (2 exs USNM); “Dajabon Province, 13 km S. Loma de Cabrera, ca. 400 m, 20–22.V.1973, Don & Mignon Davis” (1 ex. USNM); “Juan Dolio 10–18.XII.2005, R. Fencl leg.” (3 exs NHMP). Jamaica: “Porus, 23.II.1937 ”, “Sta 414, Chapin and Blackwelder”, “Flying at dusk” (2 exs USNM); “Try., Good Hope, VIII. II.1966, A.T. Howden” (2 exs USNM); “Parrish, St. Catherine, Worthy Park Est.”, “R.E. Woodroof, 17.V.1969, blacklight trap” (3 exs USNM). Haiti: “Miragoane, 30.X–2.XI.1934, Darlington” (1 ex. USNM); “Etang Lac haux, SW peninsula, under 1000 ft, 26–27.X.1934, Darlington” (1 ex. USNM). Panamá: “Canal Zone, Albrook Forest site, 28–29.V.1968, BLT R.S. Hutton” (2 exs USNM); “Canal Zone, 5 mi SSW Gatun Dam, 30.XII.1987, MacDonald & Schiefer”, “William H. Cross Expedition” (2 exs MEM); “Darien, 5 km W Meteti, 9.I.1988, MacDonald & Schiefer”, “William H. Cross Expedition” (1 ex. MEM). Paraguay: “Dep. Guaira, Garay, 20.VIII.1992, U.M. Drechsel leg” (1 ex. LHB); “Dep. Boqueron, X.1990, Col. New Land” (1 ex. NMW); “Dep. Central, Capiata, 3.X.1994 ” (1 ex. NMW); “Jejuí-Mí, 18–20.XII.2003, light trap, leg. M.C. Michat” (22 exs MCMC); “Dep. Alto Paraguay, rd. to Fortín Patria, 3.XII.2002, light trap, leg. M.C. Michat” (12 exs MCMC); “Dep. Alto Paraguay, Defensores del Chaco N.P., Fortín Madrejón, 23.XI.2002, light trap, leg. M.C. Michat” (7 exs MCMC); “Dep. Presidente Hayes, Transchaco rd., 5 km SE Pozo Colorado, 22.XI.2002, light trap, leg. M.C. Michat” (1 ex. MCMC); “Dep. Concepcion, Est. San Luis, 8.IX.1997, Bach im Cerrado-Wald, Uferschotter [= brook in Cerrado-Forest, shore gravel], leg. Drechsel” (1 ex. NMW). Virgin Islands: “St. Croix, Bethlehem, grassy pond, 11–15.II.1966, Paul J. Spangler” (107 exs USNM, MTP).

Additional material studied. Jamaica: Moneague, 26.VIII.1934, Darlington (2 females USNM –most likely belonging to this species).

Diagnosis. Dorsally very similar to other species of the genus, except for (frequently) very elongate body and elytra markedly sinuate subapically. Underside dark, at least in part, darker than in any other Laccomimus species. Median lobe of aedeagus distinctive, apex ending in characteristic small, bird head-like expansion ( Fig. 103 a, b).

Description. Habitus ( Fig. 65 ). TL: 2.1–2.5 mm; MW: 1.0– 1.3 mm (holotype: TL: 2.3 mm; MW: 1.2 mm); A- TL: 2.3 mm; A-MW: 1.2 mm (NUM: 67 exs); body elongate, drop-shaped, elytra often markedly sinuate subapically.

Colour. Head and pronotum paler than elytra. Head testaceous or reddish-brown, frequently darker between eyes; pronotum testaceous to reddish, often with darker, elongate marking along hind margin. Elytra brown, with quite sharply defined pale subbasal band, often fragmented in spots; subapical lateral yellow band extending to apex; a third, lateral, less defined yellow marking is frequently visible. Underside brown or dark brown, normally head, prosternum, epipleura, metacoxal processes, and last abdominal ventrite paler. Dark areas always present, at least in part, although very variable in extension. Antennae and mouthparts testaceous. Legs uniformly testaceous except for dark metatarsi.

Structures and sculpture. Head smooth, shiny, with fine microreticulation of rounded cells. Pronotum with microreticulation as on head, shiny, with faint iridescence. Few scattered punctures mostly along fore and hind margins. Elytra with subapical sinuation quite pronounced; smooth with quite impressed reticulation and intense iridescence. Prosternal process ( Figs 29–31 ) slightly elevated, rounded at tip. Lobes of metacoxal processes rounded in both sexes ( Fig. 40 ).

Male. Last abdominal ventrite tectiform, with antero-lateral sides markedly sinuate ( Fig. 42 ). Outer claw of forelegs scimitar-shaped ( Figs 50 ; 70). Median lobe of aedeagus, in left lateral view ( Fig. 103 a, b), slender but robust, base and distal portion forming a very wide angle, then straight, regularly narrowed to apex, ending in characteristic small, bird head-like expansion. In dorsal view ( Fig. 113 ) similar to that of L. pumilio . except for a visible constriction on left side, close to base, and apical fourth strongly narrowed with hooked tip; dorsal lamina straight along its whole length; ejaculator groove wide, gradually narrowed to apex. Left paramere ( Fig. 103 c) curved, gradually tapering to apex.

Female. Last abdominal ventrite triangular, very narrowly rounded to subtruncate at apex ( Fig. 43 ). Lateral tergites thin, partly membranous. Gonocoxal blade as in preceding species; ramus ( Fig. 120 ) similar to that of L. pumilio . except for teeth a bit larger.

Distribution. Argentina, Bolivia, Brazil (Mato Grosso), Dominican Republic, Haiti, Jamaica, Panamá, Paraguay, Venezuela, Virgin Islands ( Figs 126 ; 128).

Ecology. Field data suggest a wide ecological range with collections from both stagnant and running waters. In Young’s letter to Spangler, the following field observations are given for this species in the Virgin Islands: “adults and larvae of Laccomimus were collected from shallow water at the edge of the pond in an open field on St. Croix (…). They were found beneath a mat of wiry grass growing over the margin of the pond. By bending the mat of vegetation back onto the bank and anchoring it, the shallow margins of the pond were exposed and could be easily worked with a dip net. Vegetation accumulated in working the pond margin with the net was dumped onto a ground cloth. Adult Laccomimus were surprisingly agile. They jumped rapidly much like fleas as soon as they were dumped onto the cloth and they often jumped completely off the cloth and escaped. Most of the adults would have escaped without the rapid use of a suction bulb aspirator. The slow-moving larvae could be easily hand picked from the cloth.” In Calilegua National Park ( Argentina) some specimens were collected from the margins of a large vegetated pond at 750 m a.s.l., partially exposed to direct sunlight, with turbid water rich in organic matter, sparse marginal vegetation and absence of floating vegetation (Fig. 130).

Etymology. The specific name is a noun in the genitive case which was given in litteris by Frank N. Young and Paul J. Spangler, in honour of the collector Carlos Bordon (cf. Young 1974: 2, 3).

Notes on variability. In spite of its wide distribution, no relevant morphological variation was observed between populations. An exception is the partially dark underside, which is always present, but varies in extent (often this is the only diagnostic feature to distinguish females of this species). The shape of the median lobe is very constant among the studied specimens.

Remarks. This species is similar to L. pumilio in the modified male anterior claws, the shape of the prosternal and metacoxal processes, and the female genitalia. However, it is highly characteristic in the dark underside and in the aedeagal features mentioned above.

Figures

FIGURES 1 – 7. 1) Habitus of Laccomimus bolivari, dorsal view (Photo A. E. Z. Short); 2) habitus of Laccodytes apalodes, dorsal view (Photo A. E. Z. Short); 3 – 7) SEMs of Laccomimus species (females): 3) habitus of L. alvarengi, dorsal view; 4) habitus of L. bordoni, dorsal view; 5) pronotum of L. alvarengi, dorsal view; 6) pronotum of L. bordoni, dorsal view; 7) pronotum of L. bordoni, dorsolateral view.

FIGURES 103 – 106. Male genitalia in Laccomimus species, left lateral view: 103) L. bordoni, a) median lobe, b) magnification of apex of median lobe, c) left paramere, showing apex in different positions, d) right paramere; 104) L. spangleri, a) median lobe, b) left paramere; c) right paramere; 105) L. bolivari (holotype), a) median lobe, b) magnification of apex of median lobe, c) left paramere, d) right paramere; 106) L. bolivari (Suriname), a) median lobe, b) magnification of apex of median lobe.

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 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 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 116 – 121. Female genitalia and cladogram. 116 – 120) Female genitalia in Laccomimus species, left lateral view: 116) L. distinctus (Paraguay), a) left gonocoxa, b) ramus; 117) L. malkini (Perú), a) left gonocoxa, b) ramus; 118) L. alvarengi (Brazil), a) left gonocoxa, b) ramus; 119) L. variegatus (Perú), a) left gonocoxa, b) ramus; 120) L. bordoni (Bolivia), ramus (arrow indicates lateral proximal process of ramus). 121) Single most parsimonious cladogram rooted between ingroup and outgroup, with character changes mapped for each clade. Solid rectangles indicate unique character state transformations; open rectangles indicate homoplasious character state transformations. Support values are indicated on each branch as Bremer / Bootstrap.

FIGURES 126 – 129. Distribution maps of Laccomimus species: 126) L. bordoni in South America; 127) L. bolivari (full circles), L. youngi (single open square in Brazil); 128) L. pumilio (open circles), L. alvarengi in Central America (single triangle in Panamá), L. spangleri (stars), L. bordoni in Central America (asterisks); 129) L. improvidus.