Desmopachria lateralis, Miller, 2022

Miller, Kelly B., 2022, Nineteen new species of Desmopachria Babington, 1841 (Coleoptera, Adephaga, Dytiscidae, Hydroporinae, Hyphydrini) with notes on the taxonomy of the genus, ZooKeys 1136, pp. 1-56 : 1

Desmopachria lateralis sp. nov.

Figures 18-22 , 77

Type locality.

Venezuela, Amazonas State, Communidad Caño Gato, on Rio Sipapo, 4°58.838'N, 67°44.341'W.

Diagnosis.

This species is particularly distinctive because of the lateral carina extending along the lateral margin of the elytron from the humeral angle almost the entire length of the elytron. Specimens are moderately large for Desmopachria species (TL = 1.7-1.8 mm). The dorsal color pattern is distinctive in many specimens with most of the elytron brown with a broad region longitudinally along the suture dark brown (Figs 18 , 19 ). The male genitalia are distinctive with the median lobe in lateral aspect elongate, sublinear along the dorsal margin and medially expanded along the ventral margin and apically narrowly rounded (Fig. 20 ). In ventral aspect the median lobe is broad with the lateral margins slightly convergent to the broadly truncate apex (Fig. 21 ). The lateral lobe is moderately broad basally and narrowed apically to a narrowly rounded apex, apically with a small, elongate apical tooth (Fig. 22 ). See under Desmopachria apicodente for additional diagnostic differences between that species, Desmopachria amyae , and Desmopachria lateralis .

Description.

Measurements. TL = 1.7-1.8 mm, GW = 1.3-1.4 mm, PW = 1.0-1.1 mm, HW = 0.6-0.7 mm, EW = 0.3-0.4 mm, TL/GW = 1.3-1.4, HW/EW = 1.9-2.0. Body very broad, rounded, laterally broadly rounded, lateral margins slightly discontinuous between pronotum and elytron; dorsoventrally somewhat compressed.

Coloration. Head pale orange. Pronotum pale orange with narrow dark area medially along posterior margin. Elytron dark orange, with broad dark brown band longitudinally along suture, also with small diffuse, pale macula at apex, and paler diffuse areas anteromedially (Fig. 18 ). Ventral surfaces yellow to orange.

Sculpture and structure. Head broad, short; anterior margin of clypeus finely margined with continuous narrow bead, bead slightly more expanded medially; surface of head shiny, punctures extremely fine, nearly impunctate; eyes large (HW/EW = 1.9-2.0); antennae short, scape and pedicel relatively large and rounded, flagellomere III long and slender, apically expanded, antennomeres IV-X short and broad, antennomere XI elongate, apically pointed. Pronotum short, lateral margins short, curved with continuous narrow bead; surface shiny, punctation very fine over most of surface, larger and denser posteromedially. Elytron broad, laterally broadly curved; surface shiny, punctation variable, some punctures arranged into indistinct series, especially anteromedially (Fig. 18 ); lateral margin, dorsad of epipleural carina, with distinct, longitudinal carina extending from humeral angle most of length of elytron (Fig. 19 ). Prosternum extremely short, longitudinally compressed, medially flattened; prosternal process short, broad, flattened, apically pointed. Metaventrite broad and evenly smoothly convex medially, surface shiny, impunctate; metaventrite wings extremely slender. Metacoxa with medial portion short, <1/3 length of metaventrite medially, metacoxal lines slightly sinuate, divergent anteriorly; lateral portion of metacoxa extremely large, anteriorly strongly expanded; surface shiny, impunctate, slightly rugulose. Metatrochanter very large, longer than length of ventral margin of metafemur; legs otherwise not noticeably modified. Abdomen with surfaces shiny and smooth, surface impunctate.

Male genitalia. Male median lobe in lateral aspect moderately broad, elongate, straight, with submedial expansion on ventral surface, apex narrowly rounded (Fig. 20 ); in ventral aspect elongate and broad, apex broadly subtruncate, slightly emarginate (Fig. 21 ). Lateral lobe elongate, moderately broad medially, apically narrowed to apex, apex sharply curved mediad with small but distinctive elongate “tooth” at apex (Fig. 22 ).

Sexual dimorphism. No obvious external sexual dimorphism was observed.

Variation. Specimens vary in the extent of the color pattern on the elytron and intensity of coloration, some of which is related to teneral condition. Some specimens have pale regions barely visible and they are weakly delimited, others have a distinctive pattern on the dorsal surface.

Etymology.

This species is named Desmopachria lateralis , from the Latin for the lateral carina on the elytron.

Distribution.

This species is known only from Amazonas State, Venezuela (Fig. 77 ).

Type material.

Holotype in MIZA, male labeled, "VENEZUELA: Amazonas State 4°58.838'N, 67°44.341'W; 95m Communidad Caño Gato, on Rio Sipapo; 16.i.2009; leg. Short, Miller, Camacho, Joly, & García VZ09-0116-01X; along stream/ SM0843192 KUNHM-ENT [barcode label]/ HOLOTYPE Desmopachria lateralis Miller, 2021 [red label with black line border]." Paratypes, 1 in SEMC labeled same as holotype except with “… / SM0843335 KUNHM-ENT [barcode label];" 14 in MSBA, MIZA, and SEMC labeled, "VENEZUELA: Amazonas State 5°20.514'N; 67°45.315'W, 87m S. Communidad Porvenir 15.i.2009; leg. Miller & Short VZ09-0115-03B; small streamlet …”; 10 in USNM and MSBA labeled, "BRAZIL: Para:Rio Zingu Camp (52°22'W. 3°39'S) Altamira (ca 60km S.) 11 Oct 2986 P.Spangler & R.Crombie/ …” Each paratype with different barcode labels (Table 1 ) and all paratypes with “… PARATYPE Desmopachria lateralis Miller, 2021 [blue label with black line border]."

Figures

Figures 13 - 27. Desmopachria apicodente - group species. (13 - 17) Desmopachria apicodente 13 habitus 14 male median lobe, right lateral aspect 15 male median lobe, ventral aspect 16 male median lobe and lateral lobes, ventral aspect 17 right lateral lobe, right lateral aspect (18 - 22) Desmopachria lateralis 18 habitus 19 left elytron, left lateral aspect 20 male median lobe, right lateral aspect 21 male median lobe and right lateral lobe, ventral aspect 22 right lateral lobe, right lateral aspect (23 - 27) Desmopachria tumida 23 habitus 24 left elytron, left lateral aspect 25 male median lobe, right lateral aspect 26 male median lobe, ventral aspect 27 right lateral lobe, right lateral aspect. Scale bars: 1.0 mm for habitus drawings.

Figures 76, 77. Desmopachria species distributions. 76 ungrouped Desmopachria species 77 Desmopachria apicodente species group.