Desmopachria cavia, Braga, Rafael Benzi & Ferreira-Jr, Nelson, 2010

Braga, Rafael Benzi & Ferreira-Jr, Nelson, 2010, Four new species of Desmopachria Babington (Insecta, Coleoptera, Dytiscidae) from the Amazon river floodplain, Zootaxa 2415, pp. 33-42 : 37-38

Desmopachria cavia sp. nov.

( Fig. 3 )

Diagnosis. Anterior clypeal margin dorsoventrally compressed and indistinctly beaded; antennomeres V–VII lobate. Pronotum wider medially, lateral bead very narrow without basal striae. Elytron yellow with brown spots and fasciae; small macula in middle of basal margin, large macula in anterior half of suture, submarginal fascia in apical two-thirds, sutural fascia extending from base to submarginal fascia ( Fig. 3 a). Depression of last abdominal segment with edge prominent with interior covered with setae ( Fig. 3 b). Aedeagus apex bifid. Parameres with slight constriction in middle, truncated at apex; in dorsal view with subapical digitiform articulated projections emerging from grooves; one tuft of subapical bristles in ventral view ( Figs 3 c–e).

Description. Holotype male: total length 1.44 mm; maximum width 0.96 mm; elytral length 0.74 mm; maximum width of pronotum 0.93 mm.

Body rounded. Head inconspicuously punctate; anterior clypeal margin dorsoventrally compressed and indistinctly beaded; antennae with scape rounded, pedicel narrower and longer than flagellomeres; antennomeres V–VII lobate. Pronotum inconspicuously punctate, wider in middle, lateral bead very narrow, without basal striae; prosternal process small and setiform; metasternum, metacoxae and abdomen with small, scattered, fine punctures. Tarsi pentamerous without modifications. Elytron very fine and obscurely punctate; second abdominal segment with long mesal bristle. Last abdominal segment with depression having edge distinct and with interior covered with bristles ( Fig. 3 b). Aedeagus short, reaching half length of parameres, with bifid apex. Parameres moderately wide in basal two-thirds with slight mesal constriction and abruptly narrowed in apical third; apex truncate; in dorsal view with subapical digitiform articulated projections emerging from grooves; one tuft of subapical bristles, in ventral view ( Figs 3 c–e).

Coloration. Head and pronotum yellow; antennomeres VIII–XI brown. Elytron yellow with brown maculae and fasciae; small macula in middle of basal margin, large macula in anterior half of suture, submarginal fascia in apical two-thirds, sutural fascia which goes from base to submarginal fascia ( Fig. 3 a). Ventral view light brown, metaesternum and metacoxae dark.

Variation. Body measurements variable in total length 1.34–1.54 mm; maximum width 0.86–1.02 mm; elytral length 0.77–0.80 mm; maximum width of pronotum 0.86–0.96 mm.

Type-material. Holotype ♂, INPA (Coleop Holotipo INPA 308); Brasil, Amazonas, Paraná da Trindade, Lírio do Vale, Lago do Albano, 24/09/2003, -2,41418, -57,49993, Ferreira-Jr N. & de Marco P. Paratypes - INPA (Coleop Paratipo INPA 308 [1-139]) 139 ind., Brasil, Amazonas, Anamã, Boa Esperança, Lago Bom Jesus, 16/09/2003, -3,65812, -61,49109, Nessimian J. L. & Hamada N.; INPA (Coleop Paratipo INPA 308 [140-187]) 48 ind., Brasil, Amazonas, Manacapuru, Cristo Ressuscitado, Lago Galo (Camoa), 17/09/2003, - 3,57995, -60,82906, Nessimian J. L. & Hamada N.; INPA (Coleop Paratipo INPA 308 [188-197]) 10 ind., Brasil, Amazonas, Itacoatiara, Ilha da Trindade, Paraná da Trindade, 22/09/2003, -3,31345, -58,73231, Ferreira-Jr N. & de Marco P.; INPA (Coleop Paratipo INPA 308 [198-271]) 74 ind., Brasil, Amazonas, Paraná da Trindade, Lírio do Vale, Lago do Albano, 24/09/2003, -2,41418, -57,49993, Ferreira-Jr N. & de Marco P.; INPA (Coleop Paratipo INPA 308 [272]) 1 ind., Brasil, Amazonas, Parintins, Menino Deus, Paraná, 25/09/ 2003, -2,54210, -56,52305, Ferreira-Jr N. & de Marco P.; INPA (Coleop Paratipo INPA 308 [273-274]) 2 ind., Brasil, Pará, Juriti, Recreio, Paraná, 26/09/2003, -2,06549, -55,56264, Ferreira-Jr N. & de Marco P.; INPA (Coleop Paratipo INPA 308 [275-276]) 2 ind., Brasil, Pará, Santarém, Santana do Ituqui, Lago Maicá, 30/09/ 2003, -2,51221, -54,32885, Ferreira-Jr N. & de Marco P.; DZRJ ( Coleoptera 2211 ); 3 ind., Brasil, Amazonas, São Paulo de Olivença, Bom Sucesso, Lago Ventura, 03/09/2003, -3,46474, -69,00533, Nessimian J. L. & Hamada N.; DZRJ ( Coleoptera 2213 ) 15 ind., Brasil, Amazonas, Santo Antônio do Içá, Vila Presidente Getúlio Vargas, Lago do Espanhol, 04/09/2003, -3,12291, -67,97323, Nessimian J. L. & Hamada N.; DZRJ ( Coleoptera 2214 ) 5 ind., Brasil, Amazonas, Jutaí, São Raimundo, Lago do Bosco, 06/09/2003, -2,68867, - 66,87529, Nessimian J. L. & Hamada N.; DZRJ: ( Coleoptera 2217 ) 142 ind., Brasil, Amazonas, Fonte Boa, Fonte Boa, Lago Ressaca Grande, 08/09/2003, -2,47399, -66,15474, Nessimian J. L. & Hamada N.; DZRJ: ( Coleoptera 2219 ) 1 ind., Brasil, Amazonas, Tefé, São Francisco da Boca da Capivara, Barra do Solimões, 09/ 09/2003, -3,28228, -64,62169, Nessimian J. L. & Hamada N.; DZRJ: ( Coleoptera 2220 ) 2 ind., Brasil, Amazonas, Tefé, São João do Catuaí, Lago da Piranha, 11/09/2003, -3,62524, -64,18968, Nessimian J. L. & Hamada N.; DZRJ: ( Coleoptera 2221 ) 96 ind., Brasil, Amazonas, Codajás, Urucurizinho, Lago Cuxuará, 15/ 09/2003, -3,97121, -61,96065, Nessimian J. L. & Hamada N.

Etymology. The specific epithet is the Latin adjective cavia meaning “depression” or “excavated” referring to the prominent depression in the surface of the last abdominal ventrite.

Taxonomic notes. This new species belongs to the convex group sensu Miller (2001) in having the subapically articulated projections on the parameres. This new species has similar male genitalia to D. pilosa and D. signata . However D. cavia sp. nov. can be distinguished from D. pilosa by having the aedeagus with the apex bifid. D. cavia also differs from D. signata in having the aedeagus length more than half the paramere length and in having the colour patterns lighter with a conspicuous difference in shape. Additionally, D. cavia can be distinguished from the other two species by being larger, having the elytron colour pattern different and the depression on the last abdominal ventrite.

Figures

FIGURES 3 – 4. 3) Desmopachria cavia sp. nov. 4) D. nigrocapitata sp. nov. a) Dorsal habitus; b) last visible abdominal ventrite; c) male genitalia, dorsal view; d) male genitalia, ventral view; e) male genitalia, dorsal view with cover slips. Scale in dorsal habitus = 1.0 mm.