The genus Doyère, 1840 (Tardigrada) in South America with descriptions of two new species from Argentina and discussion of the feeding behaviour in the family Milnesiidae.

BACKGROUND

The diversity and distribution of the tardigrades in South America are rather poor and selective, as is information about their feeding behaviour and diet. To date, only ca. 210 tardigrade taxa have been reported from the region of South America. In the present paper, we provide an update of the distribution of the genus inSouth America and discuss some aspects of the feeding behaviour in the family Milnesiidae.

RESULTS

In seven moss samples collected in the Argentinean province of Río Negro, 31 specimens, 4 exuviae and 32 eggs belonging to the genus were found. Among them, four species were identified: sp. nov., sp. nov., and . By its dorsal sculpture, sp.nov. is most similar to sp.nov., and, butit differs from and mainlyby having a different claw configuration and from e and by having stylet supports inserted in a more caudal position and by some other morphometriccharacters. In the width of its buccal tube and the claw configuration [3-3]-[3-3], sp.nov. is most similar to , and,but it differs from them mainly by having a sculptured dorsal cuticle and by some other morphometric characters.

CONCLUSIONS

The study discusses distribution and taxonomic problems of the species known from South America. As of now, nine taxa are known from this region (including two new species reported in this paper). Additionally, the study broadens our knowledge of tardigrades' feeding behaviour, provides some details about their diet and suggests that the type of prey chosen by some species belonging to the family Milnesiidae may be associated with the width of their buccal tube.