Dichotomius (Luederwaldtinia) foveicollis (Kirsch, 1871)

Montoya-Molina, Santiago & Vaz-De-Mello, Fernando Z., 2020, Rediscovering Dichotomius foveicollis (Kirsch, 1871) (Coleoptera: Scarabaeinae), new combination, revalidation and other taxonomic notes, Journal of Natural History (J. Nat. Hist.) 53 (45 - 46), pp. 2763-2769 : 2764-2767

Dichotomius (Luederwaldtinia) foveicollis (Kirsch, 1871) revalidated, new combination

( Figure 1 (a-g), Figure 2 (a-b), Figure 3 ).

Pinotus foveicollis Kirsch, 1871 357 (original description)

Pinotus agenor Harold, 1869 (pars); Luederwaldt 1929 (synonym); Blackwelder 1944

Diagnosis

Dichotomius foveicollis is differentiated from any species in the Dichotomius agenor species-group by the following combination of characters: Large male cephalic carina bituberculate as wide as high bearing an acute apex at each tubercle. Pronotum anterior edge with medial depression, apex with two small under-developed lobes. Longitudinal groove (sulcus) firmly impressed and complete, joining anterior and posterior margins through the middle. Males sixth sternite broader medially; pygidium gibbous at apex, without margin. Morphological variation in smaller males is not listed. Females are distinguished from males in displaying completely rugose head surface, pronotal anteromedial edge with weak slope and sixth abdominal sternite broader medially.

Description

Male ( Figure 1 (a-g)) Body length: 20.54 mm. Pronotum and ventral surface shiny, elytra opaque. Head. anterior surface rugose not extending posteriorly to base of cephalic carina. Interocular space shiny, smooth and displaying some fine punctures. Clypeus with a central emargination separating two rounded dorsally curving clypeal teeth. Genae weakly rugose. Clypeal margin distinct at clypeal teeth. Cephalic carina as wide as high, bearing an acute apex at each tubercle ( Figure 1d ). Clypeo-genal suture distinct and clypeo-genal junction greatly emarginate developing a protuberance on posterior side of clypeo-genal junction. Ventral clypeal process longitudinally enlarged into conic form. Pronotum. wider than long. Pronotal disc shiny, presenting fine punctures. Margins smooth, anterior margin expanded, thicker medially. Anterior edge with medial depression, apex with two small under-developed lobules. Longitudinal groove (sulcus) firmly impressed, complete and joining anterior and posterior margins through the middle ( Figure 1a ). Hypomeron anterior portion with weak excavation, with rounded ocellate setigerous punctures, each of these punctures separated by the width of a puncture. Hypomeral medial disc smooth and shiny, not covered by setae or any punctures. External margin bearing multiple rows of disorganised setae, all approximately of same length when viewed dorsally. Abdomen. prosternum surface shagreened, with setigerous punctures, setae brown and half length of setae on external margin of hypomeron. Mesosternum covered by ocellate-setigerous punctures, in the middle of which, there is microscopic punctuation. Setae as long as the ones found in prosternum. Metepisternum covered by setigerous punctures, dense setae covering shagreened metepisternal surface. Metasternum anterior surface near mesocoxa covered with dense pilosity. Setigerous punctures restricted mainly to anterior and lateral portions, never covering metasternal disc, punctures separated by the width or half the width of a puncture. Same type of setigerous punctures surrounding margin of mesocoxa. Longitudinal sulcus visible. Anterior margin of each sternite with ocellate punctures ( Figure 1h ). Elytra. opaque. Interstriae with shagreened microsculpture. Fine, shiny punctures arranged randomly. Striae black, weakly impressed, punctures small and as wide as striae line, separated by twice diameter of a puncture on elytral disc. Legs. metacoxa posterior and middle portions bearing row of setigerous punctures, separated by diameter of a puncture. Fore calcar spiniform. In ventral view, profemur presenting long setae in middle edge, anterior apical margin of the meso- and meta-femora with rows of long setae, denser on the mesofemura. Pygidium. delimited by margin that widens towards apex. Basal inner portion with ocellate punctures. Medial and apical surfaces finely punctured. Paramera and lamella copulatrix: as in ( Figure 1c, 1 (e-g)).

Morphological variation. Femaless ( Figure 1b ) are distinguished from males as follows: Head. surface completely rugose, denser at anterior portion. Clypeus with central deep emargination separating two rounded medial clypeal teeth which curve dorsally. Cephalic carina bituberculate as males, emargination shallow, developing two distinct cuspids. Pronotum. not modified, weak antero-medial slope. Sulcus well-marked and prominent, punctures greatly impressed, denser on anterolateral portions, separated by twice the diameter of a puncture on the pronotal disc and once or less on anterolateral margins. Abdomen. sixth abdominal sternite broader medially ( Figure 1h ). Pygidium gibbose at apex, apex without margin.

Type locality

Bogotá

Type material examined

Holotype. (female: Figure 2 ): Bogota m Kirsch {green, hw}/ Typus ! {red, p}[Senckenberg Natural History Museum of Zoology, Dresden].

Non-type material examined

ECUADOR: Azuay: Quebrada Granadillas . 224908S, 9985438E. 1300 m. Colecta Manual. 24-III-2009. WChamorro. [1♀ Setor de Entomologia da Coleção Zoológica da Universidade Federal de Mato Grosso, further as CEMT] ; Loja: Catamayo ‘ Alamala ’. 3º59 ʹ 46 ” S, 73º4 ʹ 9 ” E. 1100 m. Pitfall Excremento. 22-VIII-2010. DDomínguez. [1♀ CEMT] ; Morona Stgo: Nuevo Israel, Cordillera del Cutucú . Carroña. 28-XII-2010. GSarabia. [1♀ CEMT] ; Napo: PNSumaco. Pte Río Salado y Río Quijos . Heces. 1280 m. 19-III-2009. WChamorro. [1♀ CEMT] ; Zamora Chinchipe: Zurmi, ‘ Comunidad La Wants ’. 760967E, 9539202S. 1000 m.s.n.m. Trampa pitfall, Excremento Humano . 31-I-2013. Col . William Chamorro . [1♂ 1♀ CEMT] .

Disclaimer: Subgenera names used here refer to the taxonomic arrangement proposed by Martínez (1951). Group names refer to the oldest available species name in each group ( Luederwaldt 1929; Nunes and Vaz-de-Mello 2013) and do not constitute valid taxonomic entities according to the Code ( ICZN 1999).

Figures

Figure 1. Dichotomius foveicollis: dorsal habitus male (a), female (b), lateral view of the aedeagus (c), cephalic carina bituberculate, frontal view head (d), ventral view of the aedeagus (e), lamella copulatrix (f-g), Female ventral view showing the abdominal sternites and the pygidium, sixth sternite broader medially and pygidium gibbous (h).

Figure 2. Dichotomius foveicollis: (a). Lectotype female. (b). Lectotype labels. Senckenberg Natural History Museum of Zoology, Dresden.

Figure 3. Dichotomius foveicollis: Distribution map.