Polynoncus vazdemelloi Huchet & Costa-Silva, 2018

Huchet, Jean-Bernard & Costa-Silva, Vinicius Da, 2018, A new species of Polynoncus Burmeister, 1876 from Brazil (Coleoptera: Trogidae), Zootaxa 4524 (5), pp. 553-566 : 554-558

Polynoncus vazdemelloi Huchet & Costa-Silva , new species

( Figs. 1–3 , 11 , 13 )

Type specimens. HOLOTYPE (1♂ CEMT): BRAZIL: Pernambuco, Araçoiaba , CIMNC [= Campo de Instrução Marechal Newton Cavalcanti], 116m, V.2010, L. Iannuzzi leg. PARATYPES [15♂, 5♀ , and 44 unsexed]: BRAZIL: Pernambuco, Araçoiaba, CIMNC, 23. III.2010, Llannuzzi leg. (4♂ and 3 unsexed CJBH; 1♂, 2♀, and 13 unsexed CEMT; 1♂ and 1♀ ZUEC; 3 CJBH; 4 MNHN; 2♂ CVMD); Araçoiaba, CIMNC, 21.IV.2010, LIannuzzi leg. (8 CEMT; 1♂ and 1♀ MZSP; 1♂ and 1♀ CVMD); Araçoiaba, CIMNC, V.2010, LIannuzzi leg. (3 CEMT) ; Araçoiaba, CIMNC, 19.I.2010, R.S. Correa leg. (1 CEMT) ; Camaragibe, Aldeia , 01-30.V. 2016, 100m, - 7.977°S, - 35.006°W , I.V.P.C. Grossi leg. (2♂, 1♀ and 1 unsexed CEMT; 6 unsexed CERPE); Camaragibe, Aldeia, 01- 31.VII. 2016, 100m, - 7.977°S, - 35.006°W, I.V.P.C. Grossi leg. (1 CEMT) ; Camaragibe, Aldeia , 01-03.VII. 2016, 100m, - 7.977°S, - 35.006°W, I.V.P.C. Grossi leg. (3 CERPE) ; Recife, Dois Irmãos, UFPE [= Universidade Federal de Pernambuco] (1♂ CEMT) ; Igarassu, RECD [= Refúgio Ecológico Charles Darwin], 10.VII.2007, Silva et al leg. (1♂ CEMT) . Alagoas: Ibateguara (Dois Braços) 3.XI.2007, B.K.C. Filgueiras col. (carcaça) (2♂ CEMT) ; Ibateguara (Varjão), 19.IX.2007, B.K.C. Filgueiras col. (carcaça) (1♂ CEMT) ; Ibateguara, Serra Grande , 900'01S, 3551'19W, 05.X.2011, pitfall, Mata Atlântica, Interior, B.K.C. Filgueiras leg. (1 CEMT) . Paraíba: João Pessoa, DSE/ UFPB [= Universidade Federal da Paraíba], A.A Endres leg. (1♂ CEMT) .

Description. Male. Length: 8.0–9.0 mm, width: 5.5–6.0 mm. Oblong, convex, dorsal surface of the head, pronotum, and elytra velutinous; color uniform, light brown, reminiscent of a walnut. Elytral outline distinctly convex, maximum width posterior of middle. Winged, macropterous. Male genitalia specifically distinct ( Figs. 2– 3 ). Head: transverse, dorsal surface velutinous, the tegument finely microreticulate with sparse punctures, barely perceptible; anterior deflexed portion of clypeus triangular, sharp apically and emarginate in dorsal view; the anterior margin distinctly upturned; genae acutely pointed laterally. Front with 2 prominent, bulbous, median tubercles extending forward; flanked on both sides by 1 small additional, blunt tubercle, thus appearing quadrituberculate. Mentum subquadrangular, densely setose, surface roughly punctuate; gula convex, smooth and shiny. Eyes globose, weakly prominent from above. Antenna with dark-brown scape bearing long, orange setae; funicle inserted behind the apex; pedicel with 1 concentric row of long setae; flagellum glabrous, with the exception of a single seta located on the penultimate antennomere; club yellow with minute, golden tomentosity. Thorax: transverse, about 1.45 times as wide as long; pronotal surface sparsely but distinctly punctate; punctures small to medium, shallow. Anterior margin regularly convex, anterior angles obtusely rounded, distinctly projecting forward; base widely projecting backward in obtuse lobe; sides bulbous in front of middle, then slightly convergent in the basal half to a small protrusion located in front of the posterior angle (see Fig. 11 : Abp). Pronotal disc with 2 moderately elevated, median longitudinal ridges; extending over anterior 2/3 of pronotum; median depression shallow, distinctly constricted at middle. Median longitudinal bulge extending from the front edge to base, fused medially with the longitudinal ridges (this longitudinal bulge more-or-less marked according to the individual specimens). Median basal tubercles well differentiated, suboval, slightly laterally offset, narrowly spaced from apices of median ridges; anterior and lateral basal tubercles round apically merged together, faintly elevated. Scutellum elongate, almost twice as long as wide, sub-hastate apically. Prosternal apophysis a pointed subconical projection; metasternal depression large, distinctly concave. Elytra: suboval, almost 3 times as long as pronotum, sides convex; lateral outline smooth with sparse, short bristles; greatest width posterior to middle of elytra. Humeral callus bulbous, prominent. Odd-numbered costae with raised, oval, convex elongate tubercles, their surface with few sparse, microscopic, setiferous punctures with minute, golden bristles; each tubercle separated from each other by a distance about equal to their length. Sutural margin with widely spaced narrow tubercles; even-numbered costae with barely raised, small, round tubercles; intercostae with round, darkened punctures separated by a distance about equal to their diameter; dorsal profile visibly convex, strongly declivous apically, greatest convexity posterior of middle. Abdomen: 5 visible sternites (IV–VIII); sternite IV with rough surface; ventral surface velutinous with the exception of the median region. Legs: protibia very narrow, slightly bidentate at apex, apical portion imperceptibly dilated; outer margin with a minute anteromedian tooth, inner margin slightly arched inward; apical spur pointed forward, slightly sinuate apically, length equal to the first 4 tarsomeres combined; mesotibia slightly arched, the outer margin with a postmedian tooth; metatibia roughly straight; both mesotibia and metatibia slightly indented apically; mesotarsi and metatarsi with sparse, short, pale setae both dorsally and ventrally. Male genitalia ( Figs. 2–3 ): aedeagus symmetrical; parameres rather simple, thin, poorly sclerotized apically. Median lobe symmetrical, narrow, expanded apically, the apophysis barely dilated at apex.

Habitat and natural history. According to the localities mentioned on the labels, this new species seems to be restricted to the Atlantic Forest and Restinga, a distinct type of coastal tropical moist broadleaf forest with sandy soil. Like other members of the genus, this species can be easily collected using decaying organic matters (carcass, liver, gizzard, or feces) as bait in all seasons.

Distribution. This new species is known from littoral areas of Northeast Brazil (Nordeste): Paraíba, Pernambuco, and Alagoas ( Fig 13 ).

Etymology. This species is dedicated to our colleague Fernando Zagury Vaz-de-Mello of Universidade Federal de Mato Grosso (UFMT), a Brazilian specialist of Scarabaeoidea.

Differential diagnosis. Externally, P. vazdemelloi is most similar to P. juglans ( Ratcliffe, 1978) ( Figs. 4–6 ) and P. gemmingeri ( Harold, 1872) ( Figs. 7–9 ). It can be reliably distinguished from both species by the lateral outline of the pronotum and the shape of the antero-basal projection (Abp), being very reduced ( Figs. 10–12 ). Moreover, the general outline of the elytra is convex (subparallel in P. juglans and P. gemmingeri ), and the elytral tubercles distinctly less raised (the latter rounded rather than oval in P. gemmingeri ). Protibia very narrow, barely indented apically in P. vazdemelloi (enlarged apically in P. juglans , dilated and strongly bidentate in P. gemmingeri ). Mesotarsomeres and metatarsomeres distinctly longer than wide (length/width = 1.4) in P. gemmingeri , the claws well developed, mesotarsomeres and metatarsomeres subquadrangular (length/width = 1.1), the claws visibly reduced in P. vazdemellloi and P. juglans . The male genitalia of the three species are very distinctive: in P. juglans , the apophysis of the median lobe is spatulate apically ( Fig. 5 ), asymmetrical within P. gemmingeri ( Fig. 8 ), the apophysis simply extended and barely dilated at apex in P. vazdemelloi ( Fig. 2 ).

Figures

FIGURE 13. Distribution map of Polynoncus vazdemelloi new species.

FIGURES 1–3. Polynoncus vazdemelloi new species, Paratype ♂. 1, Habitus, dorsal view; 2, aedeagus, dorsal view; 3, aedeagus, lateral view.

FIGURES 10–12. Form of pronotum and scutellum. 10, Polynoncus juglans (after Ratcliffe 1978, modified); 11, Polynoncus vazdemelloi new species (Abp = antero-basal projection); 12, Polynoncus gemmingeri.

FIGURES 4–6. Polynoncus juglans (Ratcliffe, 1978), ♂. 4, habitus, dorsal view; 5, aedeagus, dorsal view; 6, aedeagus, lateral view.

FIGURES 7–9. Polynoncus gemmingeri (Harold, 1872), ♂. 7, habitus, dorsal view; 8, aedeagus, dorsal view; 9, aedeagus, lateral view.