Subanchonidium Hoffmann, 1968

Grebennikov, Vasily V., 2021, Sky islands of the Cameroon Volcanic Line support the westernmost clade of five new Typoderus weevils (Coleoptera: Curculionidae: Molytinae), Arthropod Systematics & Phylogeny 79, pp. 57-74 : 57

= Subanchonidium Hoffmann, 1968 syn. nov.

Anchonidium Subanchonidium Hoffmann 1968: 23 (as subgenus of Anchonidium Bedel, 1884; species included: Anchonidium baloghi ). Type species: Anchonidium baloghi Hoffmann, 1968 by monotypy.

Available evidence.

The genus Anchonidium was recently reduced to include only five West Palaearctic species (of them two from Portugal recently described, Germann 2020), while all but two Anchonidium from the Afrotropical Region were transferred to a re-defined Aparopionella Hustache, 1939 ( Grebennikov 2018). Two Anchonidium species described by Hoffmann (1968) from the Republic of the Congo as type species of two monotypic subgenera of Anchonidium were noted as belonging to neither Anchonidium nor Aparopionella ( Grebennikov 2018). A decision on the taxonomic status of these four names was long delayed by the unavailability of the type series. These historical specimens were borrowed in 2007 from Hungarian Natural History Museum (= HNHM, Budapest, Hungary) by Nicolas Maughan (Aix-Marseille University, Marseille, France; loan #4240/7343) and not returned as of September 2019, despite numerous demands (personal communication, Ottó Merkl, curator of HNHM Coleoptera collection). Requests for high-resolution images of the type specimens resulted in a low-resolution dorsal view of the holotype of A. distinctum (Fig. 1 ). The image revealed a weevil consistent with Typoderus in its appearance (parallel-sided body, effaced elytral shoulders, two longitudinal ridges on each side of pronotum, of them the internal one zig-zag shaped). The last feature is synapomorphic for the clade of Typoderus plus Lupangus . The beetle in Fig. 1 differs from Lupangus by having an anteriorly directed rostrum (more ventrally directed in Lupangus ), by lacking transverse dorsal groove behind eyes (present in Lupangus ) and by the more rounded eyes (vertical in Lupangus , fig. 4 in Grebennikov 2017). These considerations, together with sympatry and great similarity of this species with A. baloghi ( “extrêmement voisin de Anchonidium baloghi ...", Hoffmann 1968: 24) are the only data available to conclude that both species taxonomically belong to the genus Typoderus and are, therefore herein transferred to the later as Typoderus distinctus (Hoffmann, 1968) comb. nov. and Typoderus baloghi (Hoffmann, 1968) comb. nov.

Figures

Figure 1. Distribution of the genus Typoderus. Map designed using the online SimpleMappr tool (Shorthouse 2010).