Liogenys cribricollis Moser, 1921

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 : 8-11

Liogenys cribricollis Moser, 1921

Figs. 3 ; 23 .

Liogenys cribricollis Moser, 1921:140 ; Blackwelder 1944: 227 (checklist); Biezanko et al. 1949: 192 (natural history); United States Department of Agriculture 1971: 335 (natural history); Evans 2003: 208 (synonym of L. densicollis ).

Liogenys densicollis var. cribricollis: Frey, 1969: 38–39 , (key, systematics).

Type material. Liogenys cribricollis male lectotype here designated ( ZMHB): [white typeset] “Republ. Argentina / CHACO DE SANTIAGO / DEL ESTERO, RIO SALADO”, [white handwritten] “ Liogenys / cribricollis / Mos / Typen ♂”, [light red typeset] “Typus”, [white typeset] “ Liogenys / cribricollis / Mos.”, [white, outlined red, typeset and handwritten] “ Liogenys / cribricollis / Moser, 1921 / LECTOTYPE / Des. Cherman M. A.”, genitalia mounted. Paralectotypes (1): one female with the same data of the lectotype, plus the label: [white, outlined red, typeset and handwritten] “ Liogenys / cribricollis / Moser, 1921 / PARALECTOTYPE / Des. Cherman M. A.” ( ZMHB).

Non-type material (24). ARGENTINA. Salta: without locality, I.1956, Vaqueros, 1 male and 2 females ( CNCI) ; Santiago del Estero: without locality, date and collector, 1 male ( ZMHB) ; without locality and date, Wagner, 1 male ( MLPA) ; Río Salado , without date, E. Wagner, 1 male and 1 female ( MLPA) ; 1 female ( CASC) ; Chaco: Gancedo , 8.XII.1939, Biraben & Bezzi, 3 males ( MLPA) ; Santa Fé: Carcarañá, without date and collector, 1 female ( USNM) ; Córdoba: Marull, 22.I.1940, Biraben, 1 female ( MLPA), Diquecito , XI.1958, A. Martínez, 1 male ( MZSP) ; Alta Gracia , “Las Rosas”, I.1941, Monrós, 1 female ( CMNC) ; without locality, XI.1968, Arguello, 2 females ( CNCI) ; San Luis: 18 km S Arizona, 18–23.I. 1982, 250 m, H. & A. Howden, 1 female ( CMNC), Río Negro : without locality, date and collector, 1 male and 2 females ; Conesa , I.1931, J. Bosq, 1 female ( MLPA) ; Villa Regina, XII.1961 , A. Maller, 1 male and 1 female ( DZUP) .

Diagnosis. Dark purplish brown. Head and pronotum densely punctate, cribrose-like surface; elytra uniformly with bristles, clypeal emargination rounded; anterior teeth rounded; lateral margin convex and produced roundly; angle between the outer side of anterior teeth and clypeal lateral projection approximately 90º; posterior corners rounded to subangulate ( Fig. 3 A–B); inner margin of male metatibia carinate towards the apex, subapically convex, sometimes produced ( Fig. 3F ); apical inner margin with or without tooth-like projection contiguous to the smaller spur ( Fig. 3J ); two metatibial transverse carinae present only posteriorly in males, apical carina complete in females; in males protarsomere II elongate, rectangular and mesotarsomere I forming a hook-like projection towards the base ( Fig. 3G ); abdominal ventrites at the midline with abundant bristles and sometimes with scales in males ( Fig. 3E ), with sparse bristles in females; apex of parameres spatulate-like shaped, expanded laterally at the lower plane and more or less angulate ( Fig. 3K ).

Redescription. Length: 9.7–13.0 mm; width: 5.0– 6.5 mm. Dark purplish brown. Head. Densely punctate, cribrose-like surface; distance between eyes from two times to three times as wide as one eye; vertex scaly, sometimes also the inner margins of the eye, clypeal margin sometimes with bristles; clypeal emargination deep, wide and rounded, anterior teeth rounded; outer sides of anterior teeth parallel; outer margin of anterior teeth shorter than the eye; lateral margin convex and more ( Fig. 3B ) or less ( Fig. 3C ) produced roundly; distance between clypeal lateral projection and the adjacent anterior tooth longer than the basal width of the anterior tooth, distance between clypeal lateral projection and anterior margin of eye longer than one eye, angle between outer side of anterior teeth and clypeal lateral projection approximately 90º; distal maxillary palpomere, maximum width less than twice the apical width; fovea deep, extending past the transverse midline of the palpomere; antenna with 10 antennomeres, club lighter in color and longer than the funicle. Thorax: anterior margin of pronotum slightly produced medially; sides of pronotum with sparse, long bristles; pronotal disc coarsely punctate, punctures disposed tightly; posterior corners rounded to subangulate; hypomere with long bristles and scaly; mesepisternum, sides of metaventrite and metacoxae scaly abundantly, scales disposed tightly; distance between mesocoxae and metacoxae two times longer than the metacoxa; scutellum rounded, coarsely punctate. Elytra: shiny, with erect bristles disposed uniformly; elytral suture and elytron unicolored, weakly elevated; all four elytral ridges weakly defined. Legs: procoxa scaly and punctate; three protibial teeth, middle and apical equal in size, distance between basal and middle teeth equal to or longer than between middle and apical; mesofemural surface setose; mesotibia subquadrate to cylindrical in cross section, mesotibial surface coarsely sculptured; two transverse carinae, the apical carina complete; metafemur setose throughout; inner margin of male metatibia carinate towards the apex, subapically convex, sometimes produced; apical inner margin with or without tooth-like projection contiguous to the smaller spur; surface coarsely sculptured; two metatibial transverse carinae present only posteriorly in males, apical carina complete in females; metatibial apical spurs of different lengths, the larger shorter than the diameter of the tibial apex; metatarsomere I shorter than metatarsomere II and wider; in males protarsomeres I to IV enlarged, protarsomere II elongate, rectangular; mesotarsomeres not enlarged; mesotarsomere I in males ventrally produced, proximal margin spinose forming a hook-like projection towards the base; claw bifid, symmetrical, superior tooth of a claw slightly longer and narrower than the inferior; distance between teeth shorter than the inferior tooth. Abdomen: band of abundant thick scales disposed tightly beneath the outer margin of elytra; disc of ventrites scaly at the sides and with bristles at the midline, with abundant bristles and sometimes with scales at the midline in males, with sparse bristles in females; propygidium scaly tightly; pygidium slightly convex or flat; quadrate or subquadrate; pygidial width not exceeding distance between spiracles of propygidium; pygidial disc setose throughout, with scales and erect bristles; pygidial apex quadrate in males ( Fig. 3H ), rounded in females ( Fig. 3I ). Parameres: basal region slightly wider than both sections of the parameres at its maximum width, parameral split at 2/3; inner margins convex; apex spatulate, expanded laterally at the lower plane and more-or-less angulate; paramere length after the split twice as long as the basal portion or even longer; in the first case the apex is short and more angulate laterally; parameres in lateral view straight, not coplanar ( Fig. 3L ).

Type locality. ARGENTINA, “ Chaco de Santiago del Estero ” [Santiago del Estero Province] .

Geographical distribution. BRAZIL (Rio Grande do Sul) ( Biezanko et al. 1949) , ARGENTINA (Salta, Santiago del Estero, Chaco, Santa Fé, Córdoba, Río Negro ) .

Remarks. Liogenys cribricollis resembles L. opacicollis Fairmaire, 1892 ( Fig. 16 ) mainly in the body color; in the head and pronotum densely punctate, forming a cribrose-like surface; the elytra uniformly bristled; the metatarsomere I short and wide; and in males the mesotarsomere I has a ventral hook-like projection ( Fig. 3G ). This species was considered by Frey (1969) as a variety of L. densicollis . Evans (2003) proposed this name as a synonym of L. densicollis . We found many differences between the primary types of both L. densicollis (in parenthesis) and L. cribricollis : in L. cribricollis the clypeal anterior teeth are well noticeable, the clypeal lateral margin convex and roundly produced, forming an angle between the outer side of anterior teeth and the clypeal lateral projection approximately 90º (outer margins of teeth obsolete, undistinguished from the lateral margin of clypeus, which is not produced); pronotal posterior corners rounder (obtuse angle); mesotibia with basal transverse carina more conspicuous (less distinct); in females the abdominal disc with sparse bristles (bristles more abundant at the midline of the ventral disc, sides scaly); and in males, the protarsomere II is rectangular (piriform); the mesotarsomere I forms a strong hook-like projection towards its base, almost reaching it (projection sharp but less wide and long); on metatibia the inner margin is subapically convex, and the transverse carina is present only posteriorly (metatibia uniform in width, transverse carina complete); and the apex of the parameres expanded laterally in a lower plane (in a single plane). Due to all these differences, herein we revalidate the status of Liogenys cribricollis as a valid species.

As it happens among populations of L. opacicollis , populations of L. cribricollis , mainly those from Córdoba and Rio Negro ( Argentina), show differences in the shape of the clypeal margin, with emargination wider and teeth weaker; and with the apex of the parameres shorter and sharper laterally. We interpret those specimens to belong to L. cribricollis because their morphological variation is not discrete enough to consider them as a different species.

Adults of L. cribricollis were reported damaging corn in Pelotas, Rio Grande do Sul, Brazil ( Biezanko et al. 1949). Here we want to state that in Biezanko et al. (1949) it was written “molho”, and Cherman et al. (2017) misspelled it with “milho”, which is corn in Portuguese. Biezanko et al. (1949) were referring to Schinus dependens Ortega “molho, assobiadeira” ( Anacardiaceae ), currently a junior synonym of the Peppertree, Schinus polygamus (Cav.) Cabrera. The United States Department of Agriculture (1971) reported L. cribricollis attacking “Molle”, Schinus latifolius (Gillies ex Lindl.) (Anacardiaceae) in southern Brazil. These Schinus species are shrubs to tall trees native to temperate South America, although the latter is more commonly spread in Argentina and Chile ( Barroso et al. 1991). Despite Biezanko et al. (1949) and United States Department of Agriculture (1971) reports, we did not find specimens from Brazil among the studied material in any collection, so we recommend further studies reviewing the Brazilian geographical distribution for this species.

Figures

FIGURE 3. Liogenys cribricollis Moser, 1921 male lectotype views: A) dorsal, B) head and pronotum, C) variation in shape of clypeus, D) labels, E) lateral, F) mesotibia and metatibia, G) mesotarsomere I, white arrow indicates ventral side modified, H) pygidium, I) female pygidium, J) apex of metatibia, white arrow indicates projection below the spurs, and the parameres in views: K) dorsal and L) lateral.

FIGURE 16. Liogenys opacicollis Fairmaire, 1892 female lectotype views: A) dorsal, C) labels; L. densicollis Moser, 1921 male lectotype views: B) dorsal, D) labels, E) lateral, F) mesotibia and metatibia, white arrow indicates shape of metatibial margin, G) mesotarsomere I, arrow indicates modified inner margin and H) its variation, I) apex of metatibia, white arrow indicates projection below the spurs, J) pygidium, and parameres in views: K) dorsal and L) lateral.

FIGURE 23. 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).