Dendropaemon (Nigropaemon) nigritulus Génier & Arnaud, 2016

François Génier & Patrick Arnaud, 2016, Dendropaemon Perty, 1830: taxonomy, systematics and phylogeny of the morphologically most derived phanaeine genus (Coleoptera: Scarabaeidae, Scarabaeinae, Phanaeini), Zootaxa 4099 (1) : 54-55

26. Dendropaemon (Nigropaemon) nigritulus Génier & Arnaud , new species

( Figs. 26 , 82–83, 121, 158)

Type locality. Surumu, Serra Marari, Territorio Rio Branco, Brasil.

Diagnosis. The small size (less than 12.0 mm) combined with the lack of metallic luster and the elongate second metatarsal segment, which is as long as or slightly longer than the first metatarsus is unique in the genus.

Description. Male holotype ( Fig. 26 ). Body. Body small, length 9.5 mm, maximum width 4.0 mm; body subrectangular in dorsal view; dorsum narrowly flat. Color. Dorsal surface dark brown to black, glossy, lacking metallic sheen; ventrum dark brown to black; pygidium dark brown; legs reddish brown to dark brown. Head. Clypeus semicircular, anterior portion slightly upturned; clypeal teeth triangular; clypeal median emargination broadly v-shaped, clypeal edge emarginate on external side of each clypeal tooth, clypeal teeth ventral surface with a fine v-shaped carina, clypeal margin ill-defined, lacking sharp carina posteriorly, clypeal surface with transverse blunt rugulae; clypeogenal suture ill-defined, bluntly carinate internally; genal surface with ill-defined rugulae anteriorly and minute scattered tubercles posteriorly on disc, with a long blunt transverse carina; clypeofrontal carina rather low, approximately 4 times wider than high, slightly arcuate in dorsal view, simply carinate, clypeofrontal carina apical edge straight in frontal view; eyes moderately large in dorsal view, interocular ratio 4.4. Pronotum. Pronotum transverse in dorsal view, pronotal width/length ratio 1.3; disc of pronotum minutely punctate basally, puncture becoming fine anteriorly, with a fine longitudinal sulcus on posterior two-third; pronotal anterior margin wider and flat lateral to eyes; anterior portion with a broad and fine tectiform carina tuberculate medially; anterior angles surface with few ill-defined rugulae, slightly but distinctly sulcate along posterior edge of anterior margin; lateral fossae simply rounded, concave; lateral portions unmodified; pronotal basal fossae very small and more or less rounded; posterior margin well-defined, lacking crenulation and setae. Elytra. Elytra approximately as long as wide in dorsal view, elytral combined width/length ratio 0.9; elytral base lacking distinct margin, simply convex; elytral striae 1–4 fine, not bordered by a minute carina laterally, evenly impressed throughout, elytral striae 5 similar to 4 on disc, strial punctures ill-defined, adjacent strial edge encroaching on interval, stria 1 weakly impressed apically, going straight to elytral apical margin; interstriae slightly convex, minutely punctate throughout, surface glossy. Thoracic sterna. Proepisternal carina absent; metasternal median lobe angularly produced anteromedially, ventral ridge ill-defined, keel shaped. Legs. Profemur posterior surface convex, glabrous and punctate internally, posterointernal margin rather thin, evenly developed, internal edge rather wide, with a contiguous row of setae along anterointernal edge and few scattered long setae on anterior half, remaining surface smooth. Protibia with four teeth on lateral edge; internal basal angle lobate; anterior surface with long aligned row of setae internally, surface glossy or feebly microsculptured between punctures; posterior surface with some well-defined punctures externally to median carina, surface glossy between punctures, with a single interrupted setal row along lateral teeth. Mesofemur unmodified on anterointernal edge apically. Mesotibia rather short, gradually widening toward apex in anterior view; anteroapical edge slightly sinuate in anterior view, anteroapical row of setae complete; apicoanterior edge circularly indented internally; external edge more or less flat, with irregular setiferous punctures and microsculpture. Mesotarsus similar in shape to metatarsus, 3- segmented, first segment moderately elongate, approximately two times as long as wide at apex. Metafemur internal edge nearly straight and lateral edge arcuate, lacking distinct depressed area anterointernally before apex, apicoposterior edge unmodified, anterior surface with a well-defined sulcus on median half. Metatibia moderately slender, slightly widening toward apex in anterior view, anterior surface with distinct row of setae, with moderately dense minute punctures on a glossy surface, metatibial posterior surface flat between longitudinal row of setae and lateral edge, with ill-defined microsculpture. Metatarsus 3-segmented ( Fig. 121 ), first segment moderately elongate, approximately two times as long as wide at apex, with anterointernal carina well defined and almost reaching apical edge. Abdominal sternites. Sternites 3–6 longitudinally slightly convex, segment 6 slightly concave; sternites 4–6 with 1–3 unaligned rows of setae laterally, glabrous medially; sternite 7 slightly longitudinally concave medially, shorter than segment 6 along midline; pygidium with moderate to large punctures, punctures separated by one diameter or less. Male genitalia (Figs. 82–83). Parameres laterally concave before apex; surface smooth, glossy apically.

Measurements (4 males, 9 females). Length: male 9.0–11.0 (9.8±0.9), female 9.5–12.0 (10.5±0.8) mm.

Primary type data. Holotype male (CMNC): [Sept.956/ BRASIL / T. Rio Branco/ Surumu/ Sa. Marari/ Coll. Martínez] handwritten; [H. & A. HOWDEN/ COLLECTION/ ex. A. Martínez coll.]; [WORLD/ SCARAB./ DATABASE/ WSD00017011]; [HOLOTYPE / Dendropaemon / nigritulus n.sp. / Génier & Arnaud, 2014] red card.

Material examined. BRAZIL: AMAZONAS, Reserva Florestal Adolpho Ducke, 26 km NE Manaus, (2°57'S, 59°57'W), 1995–1996, coll. [anonymous]— 2 females (incl. 2 paratypes) ( BMNH); Rio Uatumã, (2°34'S, 58°9'W), i.1944, coll. [anonymous]— 1 female allotype ( CMNC); RORAIMA, [Rio] Surumu, Serra Marari [= Serra Saporá], (4°23'N, 60°45'W), ix.1956, coll. [anonymous]— 1 male (holotype) ( CMNC); COLOMBIA: ARAUCA, Tame, (6°27'33''N, 71°44'12''W), 27.vii.1976, coll. M. Cooper— 1 female (paratype) ( BMNH); GUYANA: UPPER DEMERARA-BERBICE, kurupukari, (4°40'N, 58°40'W), iv–xi.1992, coll. [anonymous]— 1 female (paratype) ( BMNH); GUYANE FRANÇAISE: PK 5, Piste KM 25, Route Régina-Saint-Georges, (4°6'54''N, 52°7'16''W), viii.2008, coll. J.L. Giuglaris— 1 female (paratype) ( ATHC); Réserve naturelle des Nouragues, (4°19'N, 52°22'W), 26.viii.2010, coll. [anonymous]— 1 male (paratype) ( COBF); same locality, 2.ix.2010, coll. [anonymous]— 2 females (incl. 2 paratypes) ( COBF); SURINAME: SIPALIWINI, Kutari River, Kwamalasamutu region, elev. 250 m (2°10'N, 56°47'W), 18–24.viii.2010, coll. T. Larsen— 2 males (incl. 2 paratypes) ( AFIC); VENEZUELA: BOLIVAR, Río Sipao, 110 km E Caicara, (7°24'47''N, 65°12'24''W), 17.vi.–4.viii.1987, coll. S. & J. Peck— 1 female (paratype) ( BDGC).

Etymology. Nigritulus , a Latin adjective referring to the uniform black coloration of this species.

Natural history. Some specimens collected using flight interception traps set in gallery forest.

Remarks. Females differs by the shape of the anterior pronotal carina is not tuberculate medially and by the lower and wider clypeofrontal carina and the finer pygidial punctation.

Variation is limited to size and coloration which is reddish brown in teneral specimens.

Figures

FIGURES 25 – 30. Dorsal habitus. 25. D. inemarginatus, female holotype; 26. D. nigritulus, male holotype; 27. D. amyntas, male; 28. D. attalus, male holotype; 29. D. lydiae, male holotype; 30. D. morettoi, male holotype.

FIGURES 118 – 125. Metatarsus, ventral view. 118. D. fredericki, holotype; 119. D. angustipennis; 120. D. bahianus; 121. D. nigritulus, paratype; 122. D. amyntas; 123. D. attalus; 124. D. lydiae, paratype; 125. D. morettoi, paratype.