Nineteen new species of Desmopachria Babington, 1841 (Coleoptera, Adephaga, Dytiscidae, Hydroporinae, Hyphydrini) with notes on the taxonomy of the genus Author Miller, Kelly B. Department of Biology and Museum of Southwestern Biology University of New Mexico, Albuquerque, NM 87131 - 0001, USA kbmiller@unm.edu text ZooKeys 2022 2022-12-16 1136 1 56 http://dx.doi.org/10.3897/zookeys.1136.72744 journal article http://dx.doi.org/10.3897/zookeys.1136.72744 1313-2970-1136-1 11C6BBFB339A4672AE662CE2B1E6321E 5D0E6613B1D05E4293ABEE4BFD1CA18A Desmopachria impunctata sp. nov. Figures 60-62 , 79 Type locality. Suriname, Sipaliwini District, Raleighfallen Nature Reserve, Voltzberg Trail, 04°40.910'N , 56°11.138'W . Diagnosis. This species includes medium-sized Desmopachria specimens in this group (TL = 1.8-1.9 mm). The elytra are more finely and indistinctly punctate than many species and punctures are of only a single, fine size. Also, the elytra are only slightly iridescent. The male genitalia are most similar to Desmopachria emarginata (Figs 54-56 ), but the apical emargination in the median lobe in Desmopachria impunctata is relatively shallower and in lateral aspect the apex is distinctly hooked ventrad (Figs 60 , 61 ). Also, specimens of Desmopachria impunctata are smaller (TL = 1.8-1.9 mm) than Desmopachria emarginata (TL = 2.0-2.2 mm). Description. Measurements. TL = 1.8-1.9 mm, GW = 1.2-1.3 mm, PW = 1.0-1.1 mm, HW = 0.6-0.7 mm, EW = 0.4-0.5 mm, TL/GW = 1.5-1.6, HW/EW = 1.7-1.8. Body very broadly oval, laterally broadly curved, lateral margins slightly discontinuous between pronotum and elytron. Coloration. Head orange to orange yellow. Pronotum evenly yellow, in most specimens paler in color than head or elytron. Elytron evenly brownish orange, iridescent, especially laterally and apically. Ventral surface of head, prosternum, head appendages, and pro- and mesolegs yellow, other ventral surfaces and metalegs orange. Sculpture and structure. Head broad, short; anterior margin of clypeus broadly curved, flattened, finely margined with conspicuous, continuous narrow bead; surface of head shiny, extremely finely and sparsely punctate; eyes moderately large (HW/EW = 1.7-1.8); 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, slightly curved with continuous marginal bead; surface shiny, extremely finely and sparsely punctate, posterior margin sinuate. Elytron broad, laterally broadly curved and rounded; surface shiny, extremely minutely punctate, punctures of even size, somewhat denser along elytral suture. Prosternum extremely short, longitudinally compressed, medially carinate; prosternal process in male very slender anteriorly, with low, indistinct medial tubercle, bifid apically with deep medial pit, in female slender anteriorly, with distinctive, small medial tubercle, apically short and broad, medially slightly carinate, apically acutely pointed. Metaventrite broad and evenly smoothly convex medially, surface shiny, impunctate medially, shallowly and minutely punctate laterally and posteromedially; metaventrite wings extremely slender. Metacoxa with medial portion short, <1/2 length of metaventrite medially, metacoxal lines slightly sinuate, divergent anteriorly; lateral portion of metacoxa extremely large, anteriorly strongly expanded; surface shiny, very finely punctate. Metatrochanter very large, subequal to length of ventral margin of metafemur; legs otherwise not noticeably modified. Abdomen with surfaces shiny and smooth, very finely and sparsely punctate. Male genitalia. Male median bilaterally symmetrical, in lateral aspect elongate, evenly broad, evenly and broadly curved on both dorsal and ventral margins, apex slightly curved ventrad, pointed (Fig. 60 ); in ventral aspect moderately broad basally, apically expanded, lateral margins broadly rounded, apex broad, medially moderately deeply emarginate, apical branches each apically broadly triangular (Fig. 61 ). Lateral lobe very broad medially, irregularly and broadly narrowed to pointed apex, with series of long setae along apicodorsal margin (Fig. 62 ). Sexual dimorphism. Male pro- and mesotarsomeres I-III slightly more broadly expanded and with ventral adhesive setae. Male and female prosternal processes different as in all Desmopachria portmanni group species. Variation. There is variation in intensity and degree of coloration across specimens. Some specimens are more evenly colored, some have greater disparity between the pale color of the pronotum and the head and elytron. Other specific variation was not detected. Etymology. This species is named Desmopachria impunctata , Latin for not punctate, for the relatively less punctate dorsal surface than in many species in the group. Distribution. This species is known from localities in Sipaliwini District, Suriname and Bolivar State, Venezuela (Fig. 79 ). Type material. Holotype in NZCS, male labeled, "SURINAME: Sipaliwini District 04°40.910'N , 56°11.138'W , 78 m Raleighfallen [sic] Nature Reserve Voltzberg trail; detrital pools along stream; leg. A. Short, C. McIntosh 30.vii.2012; SR12-0730-01B/ SEMC1113574 KUNHM-ENT [barcode label]/ HOLOTYPE Desmopachria impunctata Miller, 2021 [red label with black line border]." Paratypes, 232 specimens in MIZA, MSBA NCZS, and SEMC each with paratype label, "... / PARATYPE Desmopachria impunctata Miller, 2021 [blue label with black line border]" and different barcode labels (Table 1 ); 23 labeled same as holotype; 24 in NZCS and SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, nr Caiman Creek Camp, pools in forest; leg. Short & Bloom 19.viii.2013; SR13-0819-05B/ ..." ; 15 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, nr Caiman Creek Camp, forest detrital pools; leg. Short & Bloom 19.viii.2013; SR13-0819-05C/ ..." ; 11 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, nr Caiman Creek Camp, small streams with lots of plants & leaf litter; leg. Short & Bloom 18.viii.2013; SR13-0818-03A/ ..." ; 1 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.359'N , 56°10.052'W , 879m CSNR: Tafelberg Summit, near South Rim, pool in rock leg. Short & Bloom; 20.viii.2013 SR13-0820-01C/ ..." ; 5 in SEMC labeled, "SURINAME: Sipaliwini District 04°40.910'N , 56°11.138'W , 78 m Raleighfallen [sic] Nature Reserve Voltzberg trail; margin of stream leg. C. Maier, V. Kadosoe 30.vii.2012; sr12-0730-01A/ ..." ; 69 in NZCA and SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, nr. Caiman Crk. Camp; dipnetting by stream margins; leg. Bloom 20.viii.2013, SR13-0820-02A/ ..." ; 3 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, near Caiman Creek Camp, forest detrital pools; leg. Short & Bloom 19.viii.2013; SR13-0819-05C/ ..." ; 69 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, nr Caiman Creek Camp, pools in forest; leg. Short & Bloom 19.viii.2013; SR13-0819-05B/ ..." ; 3 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, near Caiman Creek Camp, pooled up detrital forest stream leg. Short & Bloom; 19.viii.2013 SR13-0819-05A/ ..." ; 4 in SEMC labeled, "SURINAME: Sipaliwini District 3°55.600'N , 56°11.300'W , 600m CSNR: Tafelberg Summit, nr Augustus Creek Camp, pond on trail into Arrowhead basin leg. Short & Bloom; 16.viii.2013 SR13-0816-02A/ ..." ; 1 in SEMC labeled, "SURINAME: Sipaliwini District 3°55.600'N , 56°11.300'W , 600m CSNR: Tafelberg Summit, nr Augustus Creek Camp, pools & creeks on trail into Arrowhead basin; leg. Short & Bloom 17.viii.2013; SR13-0817-01A/ ..." ; 3 in SEMC labeled, "SURINAME: Sipaliwini District 3°53.942'N , 56°10.849'W , 733m CSNR: Tafelberg Summit, near Caiman Creek Camp, stream margins: legs. Short & Bloom 18.viii.2013; SR13-0818-01A/ ..." ; 1 in MIZA labeled, "VENEZUELA: Bolivar State 6°35.617'N , 66°49.238'W , 80m Los Pijiguaos: outcrop/morichal 12.i.2009; leg Miller & Short VZ09-0112-01C: detrial [sic] pools/ ..."