Homalochilus nigripennis Cherman, 2024

Cherman, Mariana A., Basílio, Daniel S., Clarkson, Bruno, Agostinis, André O., Smith, Andrew B. T., Vaz-De-Mello, Fernando Z. & Almeida, Lúcia M., 2024, New and revised taxa of Neotropical Diplotaxini (Coleoptera: Melolonthidae): do they change the existing relationships? Revisiting systematics with morphological and molecular data, Zoological Journal of the Linnean Society 201 (1), pp. 98-135 : 114-116

Homalochilus nigripennis Cherman , sp. nov.

( Fig. 6A–G )

Type material

ZooBank: urn:lsid:zoobank.org:act:51B1BCAE-E8E3-4ED7-B406-D5691B40352A

Homalochilus nigripennis holotype, ♂, (NHMB): [white typeset] ‘Humahuaca/ Argentina / 2950 m, I.56’, [white handwritten] ‘ Homalochilus /niger Blanch’, [white, outlined black, typeset and handwritten] ‘ Homalochilus /puntatostriatus/ Bl/ det. Cherman M. A. 2018’, [red typeset] ‘ HOMALOCHILUS / NIGRIPENNIS/HOLOTYPE/Cherman M. A.’, genitalia mounted . Paratypes (117), all bearing the label [yellow typeset and handwritten] ‘ HOMALOCHILUS /NIGRIPENNIS/ PARATYPE/Cherman M. A.’. Twenty-four ♀ and 56 ♂ paratypes (NHMB) with the same data as the holotype. Among those, one ♀ and eight ♂ paratypes with an additional label [white, outlined black, typeset and handwritten] ‘ Homalochilus niger /det. 1964/A. Martínez’. One ♀ and five ♂ paratypes (NHMB): [white typeset] ‘Cienaguilla, Arg./ Jujuy, 3500m / Pena, 9.2.70 ’. One ♂ paratype (MZUC): [white handwritten] ‘1340’, [white handwritten] ‘ Argentina /Humahuaca/ Jujuy Bosq/II.44 ’, [ white typeset and handwritten] ‘ Homalochilus / punctatostriatus/M.A. Cherman det. 2016’. One ♂ paratype (MZUC) : [ white handwritten] ‘1341’, [white handwritten] ‘ Argentina /Humahuaca/ Jujuy Bosq/II.44’, [white typeset and handwritten] ‘ Homalochilus / niger Blanch /R. Gutierrez-Det ♂ /52 ’. One ♂ paratype (CMNC): [white typeset] ‘ ARGENTINA /Humahuaca/ 6 January 1956 / 2950 m.s.n.m.’. One ♂ and one ♀ paratypes (CMNC): [white handwritten] ‘ ARGENTINA /Do Cochinoca/ Jujuy /Tres Cruces/Coll. Martínez/Dic.-944’, [white typeset] ‘H. & A. HOWDEN/ COLLECTION/ ex. A.Martinez coll.’. One ♂ paratype (CMNC): [white typeset and handwritten] ‘ ARGENTINA / Jujuy /La Quiaca/COLL. DURET/1944/Cipolletti leg.’, [white typeset] ‘H. & A. HOWDEN/COLLECTION/ ex. A.Martinez coll.’ , [white typeset and handwritten] ‘ Homalochilus / niger/Blanch./A.MARTINEZ-DET.1956’. One ♀ paratype (CMNC): [white typeset] ‘Sgo. de ESTERO/RIO SALADO/ WAGNER COL’ , [ white typeset] ‘H. & A. HOWDEN/ COLLECTION/ ex. A.Martinez coll.’. One ♂ and one ♀ paratypes mounted on the same pin (CMNC): [white handwritten] ‘ ARGENTINA / JUJUY /La Quiaca/Cipolletti-leg./ Coll. Martínez/Dic.-943 ’, [ white typeset] ‘H. & A. HOWDEN/ COLLECTION/ ex. A.Martinez coll.’, [white typeset and handwritten] ‘ Homalochilus /niger/Bl./A.MARTINEZ-DET.1956’ . Ten ♂ and three ♀ paratypes (UMRM), three ♂ and one ♀ paratype (CMNC), and three ♂ and one ♀ paratype (DZUP): [white typeset] ‘ ARGENTINA /Humahuaca/ 6 January 1956 / 2950 m. s. n. m .’. Two ♂ paratypes (UMRM): [white typeset] ‘ ARGENTINA /Tres Cruces/ 6 Enero 1956 / 3400 m.’.

Holotype and 86 paratypes deposited at NHMB. Ten paratypes at CMNC. Three paratypes at CEMT. Two paratypes at DZUP. Fifteen paratypes at UMRM. One paratype at MZUC.

Diagnosis

Body, head, and pronotum entirely black, semiopaque; elytra entirely black, semiopaque, unicolorous with body ( Fig. 6A ); clypeus slightly lobed, head as long as pronotum ( Fig. 6B ); fovea of distal maxillary palpomere reaching the midline; club of antenna slightly shorter than the funicle; anterior margin of pronotum slightly constricted; disc coarsely and roughly punctate; pronotal posterior corners subangulate ( Fig. 6B ); metacoxae slightly shorter than the distance between mesocoxae and metacoxae; elytra near two times longer than the pronotum; four elytral ridges, both outermost less noticeable, sparse long bristles along the sutural ridge, scattered bristles on disc, erect long setae on apex of elytra present; protarsomere I longer than tarsomere II in both sexes; disc of ventrites with long bristles ( Fig. 6C ); pygidium subtrapezoidal ( Fig. 6D ); parameres with apex curved downwards, forming right angle with the longitudinal axis ( Fig. 6F, G ).

Holotype description

Length: 8.0 mm; width: 4.9 mm. Body short, semiopaque, sides parallel, body, head, and pronotum black, elytra on disc red and on margins black; glabrous; eyes almost entirely placed laterally, frons almost as wide as the anterior margin of pronotum; frons and clypeus coplanar; clypeus truncate; galea of maxilla with two teeth, the apical stronger; distal maxillary palpomere acuminate, fovea deep, reaching the midline of the palpomere; labium widened at the transverse midline, slightly wider than it is long; sloped from the transverse carina towards apex; apical emargination wide and rounded; antenna black, with nine antennomeres, club and as long as the funicle; pronotal anterior corners scaly, fused with hypomeron; pronotal disc coarsely punctate, simple punctures sparsely disposed; posterior corners obtuse angulate; mesocoxae and metacoxae almost equal in length; scutellum long; elytra flattened, near 1.5 longer than the pronotum; four elytral ridges, the outermost less noticeable; subapical callus strong, callus and apex of the sutural ridge at the same level; three protibial teeth, the basal tooth shorter than the other two (angle obtuse in relation to axis); mesotibia cylindrical, two transverse carina, the apical complete; metatibial spurs strongly uneven ( Fig. 6E ), the longest almost two times the diameter of the tibial apex; all tarsi cylindrical (in both sexes), protarsal claws simple, mesotarsal and metatarsal claws bifid (in females all claws bifid); protarsomere I slightly shorter than tarsomere II (in both sexes); propygidium exposed, scaly in basal region, mostly glabrous; pygidium flat, as wide as it is long; subtrapezoidal; pygidial disc glabrous, scaly basally; basal region strongly sulcate, basally widened and slightly swollen; parameres narrow, as long as the basal region, apex curved downwards, forming right angle with the longitudinal axis.

Variation

Male paratypes: Length: 8.0– 9.4 mm; width: 4.2–5.0 mm.

Female paratypes: Length: 8.0– 9.6 mm; width: 4.2–5.0 mm. The females also have the apical carina on mesotibia complete, while the metatibial spurs are strongly uneven especially in males.

Type locality ARGENTINA. Jujuy, Humahuaca [23°12ʹ45.4ʹʹS 65°20ʹ54.0ʹʹW].

Geographical distribution

ARGENTINA (Jujuy, Santiago del Estero).

Remarks

Gutiérrez (1952: 213, 214) erroneously used part of the type series in his redescription of Homalochilus niger .

Figures

Figure 6. Homalochilus nigripennis. Male holotype habitus (A); head and pronotum (B); lateral (C); posterior (D) views; metatibial apex (E); parameres in dorsal (F) and lateral (G) views. White arrow indicates the longest spur.