Cercyon gimmeli, Arriaga-Varela, Emmanuel, Seidel, Matthias, Deler-Hernandez, Albert, Viktor Senderov, & Fikacek, Martin, 2017

Arriaga-Varela, Emmanuel, Seidel, Matthias, Deler-Hernandez, Albert, Viktor Senderov, & Fikacek, Martin, 2017, A review of the Cercyon Leach (Coleoptera, Hydrophilidae, Sphaeridiinae) of the Greater Antilles, ZooKeys 681, pp. 39-93 : 44-46

Cercyon gimmeli sp. n. Figures 1 a–c, 5 a–d, 8 a–i, 15a

DNA barcodes.

GANTC002-17 to GANTC006-17

BIN ID.

BOLD:ADF7790.

Figures on Flickr.

www.flickr.com/photos/142655814@N07/albums/72157671425298360

Type locality.

Dominican Republic, Samaná Province, Monumento Natural Salto, El Limón 2.8 km SSW of El Limón, 19°16.56'S 69°26.47'W, 160 m a.s.l.

Type material.

Holotype (male): "DOMINICAN REP.: Samaná, MN Salto El Limón 2.8 km SSW of El Limón; 19°16.56'S 69°26.47'W; 160 m; 2.ix.2014, Deler, Fikáček, Gimmel. DR29a // secondary vegetation and tiny remnants of forest among coffee plantations and pastures: in horse excrement" (NMPC) [DNA extract: MF1256.1]. Paratypes: DOMINICAN REPUBLIC: Samaná: same label data as the holotype (1 males, 1 female: NMPC; 1 male: BCPC; 1 male: CNC; 1 male: CNIN; 1 male: SBNM) [DNA extract: MF1256.2 in NMPC]. La Vega: "DOMINICAN REP.: La Vega, PN A. Bermúdez, 8 km W of Manabao, 19°4.05'N, 70°51.98'W, 1140 m, 22-26.viii.2014, Deler, Fikáček, Gimmel DR16 // montane broad-leaf forest: in cow and horse excrement" (2 males: NMPC). "DOMINICAN REPUBLIC: Pr. La Vega La Cienaga de Manabao, Park Hdqt, 3-5-VII-1999, 3000 ft, R.E. Woodruff, blacklight" (1 male: FSCA). Monseñor Nouel: "DOMINICAN REP.: Msñ. Nouel, PN La Humeadora; 11.6km SSW, of Piedra Blanca; 18°44.92'N, 70°21.63'W; 636 m; 8.ix.2014, Deler, Fikáček, Gimmel DR41 // in horse excrement in moist broad-leaf forest in a valley of a small stony stream" (14 males, 2 females: NMPC; 1 male: BMNH; 1 male: CMN; 2 males: MNHNSD; 1 male: NHMW; 3 males: SBNM) [DNA extracts of both females: MF1217.1, MF1217.2 in NMPC]. Barahona: "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 26-VI/7-VII-1992: Woodruff & Skelley, flight trap" (2 males: FSCA; 2 males: NMPC). "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 26-VI/7-VII-1992: Woodruff, Skelley, Skillman. dung trap" (10 males: FSCA; 4 males: NMPC). "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 20-VII/26-VI-1992: Woodruff & Skelley, human dung" (7 males: FSCA). "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 26-VI/7-VII-1992: Woodruff, Skelley & Skillman, at light" (5 males: FSCA). "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 20-VII/26-VI-1992: Woodruff & Skelley, at day" (2 males: FSCA). DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 20-VII/26-VI-1992: Woodruff & Skelley, at light" (5 males: FSCA). "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 26-VI/7-VII-1992: Woodruff & Skelley, rat carrion" (1 male: FSCA). "DOMINICAN REP.: Prov. Barahona. nr. Filipinas, Larimar Mine: 26-VI/7-VII-1992: Skelley, day catch, beating" (1 male: FSCA).

Diagnosis.

Externally identical with other members of the Cercyon gimmeli species group, it may be only distinguished from them by the morphology of the aedeagus (Fig. 5 a–d): parameres longer than the phallobase; median lobe without spines, narrowly parallel-sided, with rounded apex.

Description.

Body. (Fig. 1 a–c) 2.8-3.5 mm long (length of holotype: 3.25 mm); long oval, 1.8 –1.9× as long as wide, widest at basal fourth of elytra; moderately convex, 3.2 × as long as high, (height of holotype: 1.05 mm). Coloration. Dorsal surface of head black, clypeus with widely yellowish anterolateral margins. Antennae and ventral surface of head, including mouthparts, brown, antennal club dark-brown. Pronotum black, with a wide, rather sharply defined creamy-white area along lateral margins, broader at anterior half. Prosternum and hypomeron brown, gradually turning black in posterior half. Elytra dark brown to black, with large, pale, rather sharply defined apical spot covering posterior quarter of elytral interval 1, and gradually larger portion on subsequent intervals up to posterior three–quarters of interval 9; two lateralmost intervals completely pale; apical area slightly darker (yellowish brown) posteriorly, with bright yellowish stripe or spots at least along its anterior border; basal portion of elytra with a pair of pale elongated dots at sides of scutellar shield. Ventral surface of mesothorax blackish to pitchy black. Metepisternum brown. Metaventrite brown with dusk anteromedial part. Abdomen brown, ventrites sometimes with dusky marks on anterior margin. Legs yellow to brown ventrally, dorsally with black markings on femora.

Head. Clypeus with rather sparse and shallow punctation consisting of crescent-shaped setiferous punctures intermixed with denser, smaller and rather transverse non–setiferous punctures; interstices without microsculpture. Anterior margin of clypeus with a narrow bead. Frontoclypeal suture conspicuous as a zone without punctuation, vanished in middle. Frons with punctation similar to that on clypeus, punctures of same shape all over, slightly sparser on sides; interstices without microsculpture. Eyes rather small; interocular distance about 6 × the width of one eye in dorsal view. Labrum membranous, nearly completely concealed under clypeus, only with narrowly exposed sinuate anterior margin. Mentum (Fig. 8a) subtrapezoid, widest at posterior fourth, about 2.1 × wider than long, 1.3 × wider at widest part than at anterior margin, concave in anterior half, with a shallow transverse impression anteromesally; surface glabrous, punctures rather small and shallow, almost vanishing anteromessally, interstices without microsculpture. Antenna with 9 antennomeres, scapus ca. 1.7 × as long antennomeres 2-6 combined; antennal club moderately elongate, about twice as long as wide, about as 1.1 × as long as scapus; antennomere 9 acuminate at apex.

Prothorax. Pronotum transverse, widest at base 2.1 –2.2× wider than long; 1.8 × wider at base than between anterior angles, 1.8 × wider than head including eyes, as convex as elytra in lateral view. Punctation moderately dense and shallow, consisting of crescent-shaped setiferous punctures intermixed with denser, smaller and rather transverse non–setiferous punctures; punctures slightly feebler on sides. Prosternum (Fig. 8b) strongly tectiform medially, medial ridge thickened in anterior half, forming a large rounded knob in lateral view (Fig. 8c). Antennal grooves distinct, with lateral margin curved, slightly feebler anteriorly.

Pterothorax. Scutellar shield 1.1 × as long as wide, sparsely punctured. Elytra widest at anterior fifth, 2.55 –2.85× as long as pronotum, 1.25 –1.35× as wide as pronotum; surface glabrous (Fig. 8d), with 10 series of punctures; series 6, 8 and 9 not reaching elytral base, serial punctures getting slightly larger laterally; intervals moderately convex; punctation of interval 1 and odd intervals composed of crescent-shaped setiferous punctures intermixed with denser, smaller and rather transverse non–setiferous punctures; even intervals with non-setiferous punctures only; all interstices without microsculpture. Humeral bulge indistinct. Mesoventral plate (Fig. 8f) narrowly elongate, ca. 5.7 × as long as wide, widest at midlength, gradually and symmetrically narrowing posteriad and anteriad to pointed apices, posterior tip slightly overlapping over anterior portion of metaventrite; surface with few sparsely arranged coarse punctures. Metaventrite with narrow median raised pentagonal area (Fig. 8g), 1.1 × as long as wide at widest portion, glabrous, weakly and sparsely punctuate, punctures with fine setae at least along margins of elevation, with bare area not reaching anterior margin; femoral lines absent; lateral parts of metaventrite densely covered by short pubescence.

Legs. Femora with sparse rather shallow punctures ventrally, interstices with weak microsculpture at bases, consisting of longitudinal lines; tibial grooves distinct. Tibiae with rather large lateral spines. Metatibiae moderately narrow and elongate, slightly bent outwards, 0.3 –0.4× as long as elytra, 5.3 × as long as wide. Metatarsus long, 0.9 × as long as metatiba, with few short but rather stout setae ventrally.

Abdomen with five ventrites, first abdominal ventrite about as long as second and third ventrites combined, with distinct median longitudinal carina (Fig. 8h) narrowing posteriad, not projecting posteriorly in both sexes; fifth ventrite (Fig. 8i) with acuminate and very weakly bulged apex in both sexes.

Male genitalia. Median projection of sternite 9 (Fig. 5d) very narrow, shorter than lateral struts, without subapical setae. Aedeagus: Phallobase (Fig. 5a) distinctly shorter than parameres, asymmetrically narrowing basally, base widely rounded. Parameres narrow throughout, slightly widened apically, subsinuate on outer face near apex, apex pointed, with a couple of setae. Median lobe (Fig. 5b) narrow throughout, indistinctly narrowing apically; apex (Fig. 5c) rounded with finely truncate tip, gonopore moderately large, situated subapically; basal portion with dorsal plate narrow and simply bifid basally. Median projection of sternite 9 (Fig. 5a) very narrow, shorter than lateral struts, without subapical setae.

Variability.

In some specimens the pale spots at sides of the scutellar shield are longer, almost reaching the second fourth of elytral length.

Etymology.

We are pleased to dedicate this species to Matthew L. Gimmel (Santa Barbara Museum of Natural History), who participated in the expedition to the Dominican Republic and collected part of the type series of this species.

Distribution.

Dominican Republic: Barahona, La Vega, Monseñor Nouel, Samaná (Fig. 14a).

Biology.

All specimens were collected in in broad-leaf tropical forests and coffee plantations and pastures, mainly on cow and horse dung, but also on human dung, rat carrion, at black-light or at day by beating.