Colasposoma subgen. Falsonerissus Pic, 1951

Zoia, Stefano, 2012, Eumolpinae (Coleoptera: Chrysomelidae) of Socotra Island, Insect biodiversity of the Socotra Archipelago (Acta Entomologica Musei Nationalis Pragae 52), pp. 449-501 : 451-453

Colasposoma subgen. Falsonerissus Pic, 1951 , stat. nov.

Falsonerissus Pic, 1951: 16 . Type species: Falsonerissus arabicus Pic, 1951 , by monotypy.

Iranomolpus Lopatin, 1979: 588 , syn. nov. Type species: Iranomolpus badius Lopatin, 1979 , by monotypy.

Andosiomorpha Lopatin, 1981: 623 , syn. nov. Type species: Andosiomorpha argentata Lopatin, 1981 , by monotypy.

Bezdekia Warchałowski, 2005: 303 , syn. nov. Type species: Bezdekia tenebrosa Warchałowski, 2005 , by monotypy.

MEDVEDEV (1996) suggested the synonymy Eryxia Lefèvre, 1890 = Iranomolpus Lopatin, 1979 = Andosiomorpha Lopatin, 1981 based on a presumed synonymy of three taxa ( Eryxia grandis Lefèvre, 1890 ; Iranomolpus badius Lopatin, 1979 and Andosiomorpha argentata Lopatin, 1981 ) and an erroneous assumption that Eryxia was described by LEFÈVRE (1890) with the type species E. grandis Lefèvre, 1890 . In reality, Eryxia was erected by BALY (1865) for E. baikiei Baly, 1865 (type species) (= E. holosericea ( Klug, 1835)) from ‘banks of Niger’. LOPATIN (2008) rejected MEDVEDEV’ s (1996) opinion without any explanation. MOSEYKO & SPRECHER–UEBERSAX (2010) adopted MEDVEDEV’ s (1996) arrangement, adding the following new synonymies: Eryxia Baly, 1865 = Bezdekia Warchałowski, 2005 , and E. grandis = B. tenebrosa Warchałowski, 2005 , based on the original descriptions and illustrations. Recently, WARCHAŁOWSKI (2010) considered Iranomolpus a valid genus with Andosiomorpha and Bezdekia being its synonyms, and he included the taxa argentatus, tenebrosus and badius in Iranomolpus as distinct species. He gave no explanation for this choice, and places this genus in Adoxini near Eryxia by means of characteristics that are not verified.

Eryxia is characterized by ‘...narrow subcylindrical form, ...squamose clothing of the body... absence of the sutural grooves between the prosternum and the anterior episterna...’ ( BALY 1865). Besides the three mentioned taxa, alternatively placed in different genera, further 13 species from the African Continent and Asia are assigned to Eryxia at present: in some cases, in particular the Asiatic species, their generic attribution needs to be reconsidered. As a matter of fact, E. grandis (type examined) does not match the characters of the genus Eryxia , particularly due to presence of well developed notosternal suture, the pronotum wide and not subcylindrical and the fine pubescence of the dorsum, and must be placed in a different genus. Moreover, in E. grandis the metatibiae are obliquely truncate at apex (while they are deeply excavate longitudinally between the raising borders in Eryxia ), claws are more divaricated, prothoracic coxae are far apart and prosternum is only a little longer than wide between the coxae (in Eryxia the coxae are closer and the prosternum is narrow, more than four times longer than wide between the coxae).

I examined the type of Falsonerissus arabicus Pic, 1951 (MNHN): it perfectly corresponds to the lectotype of Eryxia grandis Lefèvre, 1890 , even in the type locality, and I can declare F. arabicus a new synonym of E. grandis . Iranomolpus badius (type examined: ♀ ZMUH) is to be included in the same genus as E. grandis ; following LOPATIN’ S opinion (2008), I consider I. badius a distinct species. Andosiomorpha argentata must be re-evaluated as a distinct species, based on the original description and examination of specimens, and must be placed in the same genus as the above species. Eryxia socotrana Gahan, 1903 and Eryxia coracina Lopatin, 1996 are to be placed in the same genus as the above species, showing identical characteristics. Bezdekia tenebrosa must be regarded as a species distinct from Eryxia grandis , based on the illustrations of the aedeagus provided in the original description, if compared to those given here for E. grandis ( Figs. 15–16 ). On the other hand, the two taxa clearly belong to the same genus. Based on the present knowledge, Eryxia seems diffused in continental Africa, with the only exception of E. gracilipes Lefèvre, 1890 from Yemen (Aden).

The five species mentioned above do not significantly differ in their characteristics from the representatives of the large genus Colasposoma and I have no reason not to assign them to this genus; nevertheless, their peculiar habitus and distribution can justify, from my point of view, their placement in a separate subgenus Falsonerissus , identified by the claws briefly bifid, with the division starting in their midlength or even more distally. In Colasposoma , claws can be either simple, appendiculate at base or bifid, with the division starting near the base of the claw or in its basal half. The subparallel elytra and oblong body shape, the generally opaque, sometimes feebly metallic color and the close, usually short pubescence of the dorsum can distinguish Falsonerissus from Colasposoma at a first glance; nevertheless, the taxonomic value of these characters must be considered with caution because of the shown variability of these aspects within the very wide genus Colasposoma , although they are not present with equal characteristics in the same geographic area.

Based on the above mentioned facts, the following nomenclatural changes are proposed:

Colasposoma (Falsonerissus) argentatum ( Lopatin, 1981) comb. nov. for Andosiomorpha argentata Lopatin, 1981 ;

Colasposoma (Falsonerissus) badium ( Lopatin, 1979) comb. nov. for Iranomolpus badius Lopatin, 1979 ;

Colasposoma (Falsonerissus) coracinum ( Lopatin, 1996) comb. nov. for Eryxia coracina Lopatin, 1996 ;

Colasposoma (Falsonerissus) grande ( Lefèvre, 1890) comb. nov. for Eryxia grandis Lefèvre, 1890 ;

Colasposoma (Falsonerissus) socotranum ( Gahan, 1903) comb. nov. for Eryxia socotrana Gahan, 1903 ;

Colasposoma (Falsonerissus) tenebrosum ( Warchałowski, 2005) comb. nov. for Bezdekia tenebrosa Warchałowski, 2005 .

All examined species of the subgenus Falsonerissus bear a likeness to each other, which possibly did not allow authors to distinguish them correctly based on the available descriptions. In particular, it is necessary to reconsider a large part of records of ‘ Eryxia grandis ’, which possibly refer not to a single species, but to a complex of closely related species. This will be the object of a future note.

Figures

Figs. 8–18. 8–14 – Colasposoma (Falsonerissus) grande insulare subsp. nov. (8–11, 14: J holotype; 12–13: ♀, Shuab): 8 – aedeagus, apex, dorsal view; 9 – aedeagus, lateral view; 10 – tegmen; 11 – ventral sclerite of sternite IX; 12 – spermatheca; 13 – coxite; 14 – scutellum. 15–18 – Colasposoma (Falsonerissus) grande grande (Lefèvre, 1890) (Lectotype): 15 – aedeagus, apex, dorsal view; 16 – aedeagus, lateral view; 17 – ventral sclerite of sternite IX; 18 – scutellum.