Dichotomius (Luederwaldtinia) fornicatus
Creators: name: Montoya-Molina, Santiago
name: Vaz-De, Fernando Z.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Dichotomius
Dichotomius fornicatus

description: Dichotomius (Luederwaldtinia) fornicatus (Luederwaldt, 1931) Fig. 9, Map 6
Pinotus opacipennis var. fornicatus Luederwaldt, 1931: 302 (original description).
Dichotomius bosqi Pereira, 1941: 263 (original description). Syn. nov.
Dichotomius opacipennis var. fornicatus – Blackwelder 1944: 207.
Dichotomius bosqi Martínez 1959: 89.
Diagnosis
Dichotomius fornicatus is separated from other species in the group by the following combination of characters: small body size, less than 15 mm. Dorsal and ventral surface dark blue to black. Head cephalic carina, distinctly arcuate in dorsal view, middle edge slightly forward of lateral. Pronotum with abrupt anterior declivity when viewed laterally, middle surface deeper, apex of the declivity with two well-developed lobes. Elytra opaque, shagreened microsculpture.
Material examined
Holotype of P. fornicatus ARGENTINA • ♀; “Republ. Argentine CHACO DEL ESTERO, RIO SALADO” [white with black superior and inferior margins, p]/ “DÉCEMBRE” [white, p]/ “MÚSEUM PARIS 1938 COLL. A. BOUCOMONT” [green with black margins, p]/ “ Pinotus opacipennis Lueder. Forma a. Luederw. Det. 1931” [white, hw]; MNHN.
Holotype of D. bosqi
ARGENTINA • ♂; “ Sgo del ESTERO. Rio Salado. WAGNER col.” [white with black margins, p]/ “TIPO” [red with black margins, p]/ “ Pinotus bosqi P. Pereira det. 940” [white with black margins, phw]/ “23.030” [white, hw]; MZSP.
Paratype
ARGENTINA • 1 ♀; “ Sgo del ESTERO. Rio Salado. WAGNER col.” [white with black margins, p]/ “ ♀” [white, hw]/ “Paratypo” [red, hw]/ “ Pinotus bosqi ♀ P. Pereira det. 941” [white with black margins, phw] /“289” [red rounded, hw]; MLP.
Additional material
ARGENTINA – Cordoba • 1 ♀; La Para. C/esc; Dec. 1996; Monteresino leg.; CEMT • 1 ♂; C. a mano; Nov. 1990; Monteresino; CEMT • 4 ♀♀; Salta, Salado River; J.V. González and S. Macapilo leg.; 18 Jan. 2010; Snizek leg.; CEMT • 1 ♂; Rosa. Front. El Naranjo; A. Martínez leg.; MACN • 1 ♂; Tablillas; Dec. 1932 – Sep. 1933; CEMT. – Santiago del Estero • 2 ♀♀; Campo Gallo, S. del. Estero; Mar. 1943; A.F.P. B.M; BMNH 1948-159 • 2 ♂♂, 1 ♀; Choya; Oct. 1961; MLP • 1 ♂, 4 ♀♀; El Charco; Feb. 1956; MLP • 1 ♂; Matará; 12 Dec. 1939; Biraben-Bezzi leg.; MLP • 2 ♂♂; Rio Salado; Wagner leg.; MLP • 2 ♀♀; Thermas de Rio Hondo; 27–28 Nov. 1979; C. and M. Vardy B.M. leg.; BMNH 1980-67 • 1 ♀; Tucumán; Jan. 1947; CEMT • 1 ♀; Dec. 1948; CEMT • 1 ♀; Campo Bello; Mar. 1943; MACN • 1 ♂, 1 ♀; San Pedro Colalao; Feb. 1949; CEMT • 1 Ƌ; “ METATIPO”/ “Campo Gallo, S. del Estero III-1943 A.F.P.”/ “ Pinotus Ƌ bosqi P. Pereira det. 948/B.M. 1948-159.” / “NHMUK 010847032”; BMNH • 1 ♀; “ METATIPO” /“Campo Gallo, S. del Estero III-1943, A.F.P.” /“ Pinotus ♀ bosqi P. Pereira det. 948 /B.M. 1948-159” / “NHMUK 010847033”; BMNH.
BOLIVIA • 1 ♀; Cordillera, Tunalito; 8 Nov. 1946; Maldonado leg. and coll. Martinez.; CEMT. – Santa Cruz • 1 ♂, 1 ♀; Ascención; Nov. 1963; MLP • 1 ♀; Ñuflo de Cháves; Nov. 1963; MLP • 1 ♂; Yoay; Dec. 1933; G.L. Harlington leg.; CEMT • 1 ♂; Tarija, Res.Priv. Corbalán; 298 m a.s.l.; 21º39′ S 62º28′ W; chaco seco. trap. caída cebo humano; 12 Dec. 2004; C. Hamel and M. Aliaga leg.; CEMT • 2 ♂♂, 2 ♀♀; between Caiza and Creveaux; 536 m a.s.l.; 21º48′53″ S, 63º26′53″ W; blue light; OUMNH-2005-065; 05-I-2005; Mann, Hamel and Herzog leg.; CEMT • 1 ♂; Yoay and Mandipecua [Yoay y Mandeyapecua]; collector 479; Nov. 1932; Press by WCH rington; CEMT.
PARAGUAY – Boquerón • 2 ♂♂, 3 ♀♀; Loma Plata, Chaco; 8–29 Jan. 1995; CEMT. – Caaguazú • 1 ♀; Capiata; 20 Nov. 2001; C. Aguilar leg.; CEMT.
COUNTRY UNKNOWN • 1 ♂; no data; CEMT • 1 ♂, 1 ♀; B.M.; BMNH 1948-159.
Redescription
Male
MEASUREMENTS. Length: 13.35 mm. Dorsal and ventral surfaces dark blue to black. Pronotum and ventral surfaces shiny, elytra opaque.
HEAD. Surface rugosity not extending posteriorly to base of cephalic carina; interocular surface with well-impressed punctures near eyes. Cephalic carina, wider than high, distinctly arcuate in dorsal view (Fig. 9G), middle edge slightly forward of lateral. Median tubercle approximately twice as high as lateral tubercles, conic in shape and slightly curved posteriorly. Ventral clypeal process cylindrical (see Fig. 2D).
PRONOTUM. Wider than long. Antero-median declivity of pronotal disc with two underdeveloped lobes at sides when viewed laterally (Fig. 9A). Pronotal disc shiny with dense deep punctures, separated by diameter of a puncture; margins rugose, denser at antero-lateral edges. Hypomeron medial disc smooth and shiny, external margin with single row of organized and scattered setae of same length.
ABDOMEN. Mesosternum covered by large ocellate punctures separated by diameter of a puncture. Metasternum antero-medial edge smooth and shiny. Ocellate punctures restricted mainly to lateral edges, punctures separated by width of a puncture. Small ocellate punctures surrounding margin of mesocoxa (Fig. 9D). Ocellate punctures along the anterior margin of sternites; sixth abdominal sternite lower or depressed than others. Pygidium medial disc finely punctate, delimited by margin that widens towards apical part; basal inner margin rugose.
ELYTRA. Opaque. Interstriae microsculpture shagreened; fine shiny punctures disposed randomly. Striae black, weakly impressed, punctures separated by twice diameter of a puncture on elytral disc.
LEGS. Metacoxa posterior edge bearing row of small impressions, not punctures, separated by twice diameter of the impression. Setigerous punctures next to trochanter insertion larger, twice the size of small ones.
PARAMERES AND LAMELLA COPULATRIX. As in Fig. 9C, E–F.
Morphological variation
Females (Fig. 9B) are distinguished from the males as follows:
HEAD. Surface completely rugose, denser towards anterior portion. Cephalic carina trituberculate, median tubercle higher than lateral tubercles, surface punctate. Lateral tubercles narrow.
PRONOTUM. Weak medial depression, surface punctures greatly impressed separated by length of diameter of a puncture. Medial sulcus conspicuous.
Remarks
This species was first described by Luederwaldt (1931) based on a female as a variety of D. opacipennis, placing it in the inachus section as part of the lucasi group. The holotype locality was Santiago del Estero, Rio Salado, the same later used by Pereira (1941) to described D. bosqi. The description of the male of this species was by Pereira (1941). Based on the abovementioned taxonomic characters and the possibility of comparing specimens to the holotype, we suggest these species to be synonyms. Within the species group, D. fornicatus and D. rafanunezi sp. nov. are the only species where the cephalic carinae of females are trituberculate.
description: Published as part of Montoya-Molina, Santiago & Vaz-De, Fernando Z., 2021, Taxonomic review of the Dichotomius (Luederwaldtinia) agenor species group (Coleoptera: Scarabaeidae: Scarabaeinae), pp. 1-64 in European Journal of Taxonomy 734 on pages 27-29, DOI: 10.5852/ejt.2021.734.1233, http://zenodo.org/record/4542107