Cryptogonodesmus Silvestri. 1898

Golovatch, S. I., 2024, Five new species of the millipede family Trichopolydesmidae from Peru (Diplopoda: Polydesmida), Arthropoda Selecta 33 (1), pp. 1-13 : 4-5

Genus Cryptogonodesmus Silvestri. 1898

Type species: Cryptogonodesmus clavidives Silvestri, 1898 , from La Moca, southeast of Carácas, Miranda state, Venezuela [ Silvestri, 1898], non Cryptogonodesmus sensu Carl [1914] , revised by Golovatch [1994].

COMPOSITION. According to Golovatch [1994], the genus is monobasic, but presently it is to be supplemented by further three congeners: C. latior ( Golovatch, 1994) , comb.n. ex Brachycerodesmus , C. sacciformis sp.n. and C. unciger sp.n.

Indeed, because a gonopodal conformation similar to that of Cryptogonodesmus is also observed in Brachycerodesmus Carl, 1914 , both these genera had been synonymized [ Golovatch, 1992] until Golovatch [1994] revalidated Brachycerodesmus on account of a somewhat less strongly developed and more deeply sunken gonotelopodite relative to the coxite. In the light of certain new species reported here from Peru, this distinction, however, needs revision.

Brachycerodesmus has hitherto been considered as encompassing the following species: B. petersi Carl, 1914 (the type species) and B. fuhrmanni ( Carl, 1914) , both from Colombia, B. peruvianus ( Kraus, 1954) , B. oxapampaensis Kraus, 1960 and B. tarmaensis Kraus, 1959 , all from Peru, and B. latior Golovatch, 1994 , from Central Amazonia of Brazil [ Golovatch, 1994]. One more species, B. albus (Verhoeff, 1941) , is to be added as well (see below).

Whereas all above congeners except B. latior show very considerably elaborate gonopodal telopodites [ Carl, 1914; Verhoeff, 1941; Kraus, 1954, 1959, 1960], as opposed to quite simple, voluminous and sacciform ones in B. latior and Cryptogonodesmus clavidives [ Golovatch, 1994], also given two new Cryptogonodesmus species put on record below, the generic diagnosis of Cryptogonodesmus seems best to be amended as follows.

DIAGNOSIS. This genus can be characterized by a hypertrophied, simple, more or less sac-shaped and strongly exposed gonopodal telopodite relative to a moderately to strongly developed, invariably simple and poorly excavate gonocoxite [Golovatch, 1994]; a parabasal to distal solenomere located fully on mesal face, at most being short, rudimentary or missing.

Sac-shaped structures are occasionally observed in the gonopodal telopodites of some Brachycerodesmus spp. as well, but these are small and clearly subordinate to the other, more complex elements. In contrast, the sac-shaped gonotelopodites in Cryptogonodesmus are by far the main and fully exposed structures of the gonopods.