Liogenys nigrofusca Moser, 1918

Cherman, Mariana Alejandra, Basílio, Daniel Silva, Mise, Kleber Makoto, Frisch, Johannes & Almeida, Lúcia Massutti De, 2021, Liogenys Guérin-Méneville, 1831 (Coleoptera: Scarabaeidae: Melolonthinae Diplotaxini) from the Chacoan Province and its boundaries: taxonomic overview with four new species, Zootaxa 4938 (1), pp. 1-59 : 31-33

Liogenys nigrofusca Moser, 1918

Figs. 14 ; 24 .

Liogenys nigrofuscus Moser, 1918: 103 ; Frey 1969: 50 (key); Krajčík 2012: 145 (checklist); Cherman et al. 2017: 4 (generic history).

Liogenys nigrofusca: Blackwelder 1944: 227 (checklist); Evans 2003: 211 (checklist); Evans & Smith 2009: 179 (checklist).

Liogenys longicrus Moser, 1918: 100 ; Frey 1965: 145 (synonymy).

Liogenys longicra: Blackwelder 1944: 227 (checklist).

Type material. Liogenys nigrofuscus male holotype ( ZMHB): [white, typeset and handwritten] “ Argentinien / Gran Chaco ”, [white handwritten] “ Liogenys / nigrofuscus / Typen Mos ”, [red typeset] “ Typus ”, [white typeset] “ Liogenys / nigrofuscus / Mos.”

Liogenys longicrus male holotype ( ZMHB): [white typeset] “ Argentinien / Santiago del Estero ”, [white handwritten] “ Liogenys / longicrus / Typen Mos ”, [red typeset] “ Typus ”, [white handwritten] “ Liogenys / nigrofuscus / Mos. [typeset] det. G. Frey 1964 ”

Non-type material (10). PARAGUAY. Boquerón: Colonia Menonitas , VII.1945, Podtiaguin 2 males ( MZUC) ; Guachalla, A. Pilcomayo , 23.VIII.1945, P. Willim, 1 male ( MZUC) . ARGENTINA. Salta: Viñaco (15 km El Carril), 12.II.1982, H. Howden, 1 female ( CMNC) ; Coronel Moldes , XII.1958, A. Martínez, 1 female ( MZSP) ; Chaco: Pampa del Infierno [26º31’S, 61º10’W], IX.1982, A. Martínez, 1 female ( CMNC) ; Estación San Francisco, Departamento San Fernando , 16–17.X.2013, 54 m, 27°30’35.90’’S, 59°4’47.60’’W, M. Ibarra Polesel, 1 specimen ; Antequera, Departamento Primero de Mayo , 22.XII.2014, 52 m, 27°26.500’S, 58°51.459’W, M. Ibarra Polesel, 1 specimen (CARTROUNNE) ; Santiago del Estero: El Pinto, without date and collector, 2 females ( NHMB) .

Diagnosis. Length: 9.1–10.0 mm; width: 4.1–4.8 mm. Body and elytra dark brown, elongate, shiny, sides parallel; pronotum and elytra unicolored, head darker; elytra glabrous ( Fig. 14A ); pronotum roughly punctate; frons somewhat swollen and depressed medially in females; clypeal emargination deep, rounded and narrow; outer sides of anterior teeth parallel; teeth sharp; clypeal lateral margin bearing a sharp tooth-like projection, angle between this projection and the anterior teeth approximately 90º; antennae with 10 antennomeres; pronotal posterior corners rounded ( Fig. 14B ); hypomere, mesepisternum, sides of metaventrite, metacoxae and sides of ventrites with sparse long bristles ( Fig. 14C ); protibial teeth, distance between medial and apical shorter than basal and medial; mesotibia cylindrical in cross section; two strong transverse carinae posteriorly, the basal sloped, the apical complete; pygidium flat; quadrate; pygidial disc very coarsely and densely punctate, sparser in females; with bristles throughout, bristles erect, long ( Fig. 14D ); in males, inner margin of metatibia strongly carinate straight towards the apex, somewhat curved outwards ( Fig. 14C ); protarsomere II elongate; parameres narrowed medially; parameral split at the midline; apex club shaped and strongly truncate on upper margin ( Fig. 14E ); parameres in lateral view convex, not coplanar ( Fig. 14F ).

Type locality. Liogenys nigrofusca : ARGENTINA, “Gran Chaco ”; L. longicra : ARGENTINA, Santiago del Estero.

Geographical distribution. PARAGUAY (Boquerón); ARGENTINA (Salta, Chaco, Santiago del Estero).

Remarks. Frey (1965) synonymized L. nigrofusca with L. longicra , and compared this species with the preceding one in order of description, L. parallela Frey, 1965 ( Fig. 18 ). According to Frey (1965), both are almost undistinguishable but the parameres. Although L. nigrofusca resembles L. parallela in the body size and in the shape of the clypeus, especially in females, they have external differences. This species differs from L. parallela (in parenthesis) mainly in the color darker, basal transverse carina on the posterior margin of mesotibia and metatibia strong and sloped (basal transverse carina less marked and straight on mesotibia, absent on metatibia); and in the pygidium quadrate, with punctures on disc coarser and uniformly disposed.

Figures

FIGURE 14. Liogenys nigrofusca Moser, 1918 male views: A) dorsal, B) head and pronotum, C) lateral, D) pygidium, and parameres in views: E) dorsal, and F) lateral.

FIGURE 18. Liogenys parallela Frey, 1965 male views: A) dorsal, B) head and pronotum, C) lateral, D) pygidium, E) female pygidium, and parameres in views: F) dorsal, G) dorsolateral, and H) lateral.

FIGURE 24. Geographical distribution of four known Liogenys species occurring in the Chacoan province and its boundaries. Shaped points: previously known species; colors: Neotropical provinces (Morrone 2014) and Monte province from the South American Transition Zone (Roig-Juñent et al. 2018).