Helicodesmus, Golovatch, Sergei I., Geoffroy, Jean-Jacques & VandenSpiegel, Didier, 2014

Golovatch, Sergei I., Geoffroy, Jean-Jacques & VandenSpiegel, Didier, 2014, Review of the millipede family Trichopolydesmidae in the Oriental realm (Diplopoda, Polydesmida), with descriptions of new genera and species, ZooKeys 414, pp. 19-65 : 51

Helicodesmus gen. n.

Diagnosis.

19 segments (♂, ♀); pore formula normal: 5, 7, 9, 10, 12, 13, 15-18; head without modifications; paraterga poorly developed, metaterga with 3 rows of 3+3 or, more rarely, 4+4, long, bacilliform setae (regardless of lateral setae); gonopod coxae with gonocoel not deep; telopodites rather clearly exposed and transverse, but stout and remarkably complex, very strongly twisted, partly fimbriate/plumose distally, with several outgrowths of varying shapes; prefemoral part about half the height of telopodite, demarcated on lateral (not medial!) side by an oblique seminal groove running further mesad onto a medioventral outgrowth of acropodite to terminate distally, with neither a solenomere nor an accessory seminal chamber, nor a pulvillus.

Name.

To emphasize the strongly helicoid gonopod telopodite, masculine.

Type species.

Helicodesmus anichkini sp. n., by present designation.

Remarks.

This new genus is remarkable within Trichopolydesmidae in showing particularly strongly twisted gonopods, including their prefemoral parts, such that the seminal groove turns ca 180° around the highly complex transverse acropodite. Also noteworthy is the complete lack of a solenomere.