Genus Andiorrhinus Cognetti de Martiis, 1908

Andiorrhinus Cognetti de Martiis, 1908: 511 . — Michaelsen 1918: 198. — Cordero 1945: 2. — Righi 1971: 31; 1986: 124; 1993: 126. — Zicsi 1995: 592. — Feijoo et al. 2017: 57.

TYPE SPECIES. — Andiorrhinus salvadorii Cognetti de Martiis, 1908 .

DIAGNOSIS. — Setae arranged in four pairs of regular longitudinal lines. Intra-clitellar male pores. Gizzard in VI. Three pairs of calciferous glands in VII-IX, with lamellar structure. Lateral hearts in VII-IX (Cognetti de Martiis 1908; Righi 1993; Feijoo et al. 2017). Testes in X-XI within teste sacs. Two pairs of seminal vesicles in XI-XII. Spermathecae in pre-testicular segments, sometimes missing. Ovaries in XIII.

Five sub-genera are recognized, which differ from each other according to the number and position of intestinal hearts:

Andiorrhinus (Turedrilus) Righi, 1993 has the last pair of hearts in XI; Andiorrhinus (Andiorrhinus) Cognetti de Martiis, 1908 has two pairs of intestinal hearts, with the last pair in XII;

Andiorrhinus (Quibario) Feijoo, Borwn & James, 2017 has three pairs of intestinal hearts, with the last pair in XII;

Andiorrhinus (Meridrilus) Righi, 1993 has two pairs of intestinal hearts, with the last pair in XIII;

Andiorrhinus (Amazonidrilus) Righi, 1993 has three pairs of intestinal hearts, with the last pair in XIII.

DIVERSITY AND DISTRIBUTION. — Andiorrhinus comprises 47 valid species (not including the new species described here), which are distributed in Venezuela (22 species), Brazil (17 species), Bolivia (four species), Colombia (three species), Guyana (one species), Paraguay (one species) (http://taxo.drilobase.org/; Brown et al. 2023; Misirlioğlu et al. 2023).