Liogenys rotundicollis Cherman

Cherman, Mariana Alejandra, Mise, Kleber Makoto, Moron †, Miguel Angel, Vaz-de-Mello, Fernando Z. & Almeida, Lucia Massutti de, 2017, A taxonomic revision of Liogenys occurring in Brazil with an interactive key and remarks on New World Diplotaxini (Coleoptera, Melolonthidae), ZooKeys 699, pp. 1-120 : 83-86

Liogenys rotundicollis Cherman sp. n. Figs 82, 89

Type-specimen.

Holotype male, pinned, with genitalia mounted. Original labels: [white printed] "BRASIL: PI: Canto do Buriti/18-22. xi. 1991. Amarante/ Brandão Cancello & Ponte", [red printed] “HOLOTYPE” (MZSP). Holotype deposited at MZSP, Museu de Zoologia da Universidade de São Paulo, São Paulo.

Diagnosis.

Body brown; elongate, sides parallel; elytra brown, pronotum darker; clypeus quadridentate due to the tooth-like projection of the lateral margin; clypeal emargination deep and rounded; outer sides of anterior teeth parallel; clypeal lateral margin convex; pronotal anterior margin depressed throughout; pronotal posterior corners obsolete; mesotibia sub-quadrate in cross section; metacoxal disc predominantly smooth, few punctures and bristles near the base of the femur; pygidium convex, wide; pygidial width exceeding distance between spiracles of propygidium; male genitalia, total length of parameres near five times the length of their apex; strongly narrowed medially; apex harpoon-like with lateral angle projecting straight downward (Fig. 82F).

Holotype.

Male. Length: 9.0 mm; width: 4.4 mm. Dark brown. Head: distance between eyes nearly twice the width of one eye; frons equal to clypeus; clypeal emargination deep, rounded and slightly wide, outer sides of anterior teeth parallel; outer margin of anterior teeth shorter than the eye; clypeal lateral margin convex and strongly produced forming a tooth-like projection; distance between lateral and anterior tooth equal to basal width of anterior tooth, distance between lateral tooth and anterior margin of eye longer than one eye, straight angle between anterior and lateral teeth; canthus not exceeding the outer margin of the eye; distal maxillary palpomere, maximum width nearly twice width of apex; fovea shallow extending up to the transverse midline of the palpomere; labium transversely carinated, as wide as it is long; antenna 10-articulated, lamellae lighter in color and longer than the flagellum. Thorax: anterior margin of pronotum straight and depressed throughout (Fig. 82D); maximum length of pronotum exceeding the length of tarsomeres I, II and III together; disc glabrous, punctures fine and sparse; pronotal posterior corners obsolete; proepisternum with long bristles; mesepisternum sparsely scaly; sides of metasternum with short and long bristles; distance between meso- and metacoxae up to twice the length of the metacoxa; scutellum ogival, finely punctured. Elytra: shiny, glabrous, brownish, slightly lighter in color than pronotum; elytra more than three times longer than the pronotum; elytral suture darker than elytron and elevated; the two inner pairs of ridges and the outer one more distinct than the third. Legs: procoxa bristled on infra-carinal and outer surface, smooth at 12 × magnification; three protibial teeth, middle and apical equal in size; distance between basal and middle teeth slightly longer than between middle and apical; protibial inner apical spur present; mesofemural disc glabrous, bristled marginally, long bristles on the anterior margin and short in the posterior one; mesotibia sub-quadrate in cross section; disc coarsely sculptured, two mesotibial transverse carinae, the apical one incomplete; metacoxa glabrous, few punctures and bristles near the base of the femur; basal apophysis of metacoxa produced beyond the outer margin of trochanter; inner margin of metatibia carinated towards apex, apical inner surface setose; metatibial disc finely sculptured; metatibial transverse carina present posteriorly and posterior discontinuous longitudinal carina; metatibial apical spurs of different lengths, the longest one shorter than the diameter of the tibial apex; protarsomere II long; pro- and mesotarsomeres I to IV equally enlarged, less than twice as wide as metatarsi; basal metatarsomere slightly shorter than tarsomere II and equally wide; claw bifid, symmetrical, superior tooth longer and narrower than the inferior; distance between teeth shorter than the inferior tooth. Abdomen: ventrites scarcely bristled on disc; propygidium visible, bristled; pygidium convex, sub-quadrate, as wide as it is long; pygidial width exceeding distance between spiracles of propygidium; pygidial disc glabrous, bristled only on the margin of the apex, coarsely punctured, slightly depressed medially; pygidial apex sub-rounded. Parameres: basal region wider than the parameres together at its maximum width; parameral split at the third portion; total length of parameres near five times the length of their apex; strongly narrowed medially; inner margins of parameres straight; apex harpoon-like with lateral angle projecting straight downward (Fig. 82F). In lateral view parameres concave (Fig. 82G). Female remains unknown.

Etymology.

Adjective in the nominative singular. New Latin; from rotundus ( “round”) + collum ("neck, stem"). The species name is due to the rounded appearance of the posterior margin of the pronotum, due to the posterior corners obsolete.

Type locality.

BRAZIL, Piauí: Canto do Buriti [42°56'39"W; 8°06'36"S], 18-22 Nov 1991, Amarante Brandão Cancello & Ponte Coll.

Geographical distribution.

BRAZIL (PI).

Remarks.

Liogenys rotundicollis Cherman, sp. n. resembles L. parva (Fig. 68A), L. femella Cherman, sp. n. (Fig. 80A) and L. piauiensis Cherman, sp. n. (Fig. 81A) in the size and shape of the body, as well as in the quadridentate clypeus. Liogenys rotundicollis Cherman, sp. n. differs mainly in the pronotal posterior corners obsolete; the clypeal emargination deeper, making teeth slightly longer; the metacoxal disc mainly smooth, scarcely bristled near the base of the femur and the postero-external corner more rounded and the parameres strongly narrowed medially. Females remain unknown.