Tenuibiotus, Pilato & Lisi, 2011

Pilato, Giovanni & Lisi, Oscar, 2011, Tenuibiotus, a new genus of Macrobiotidae (Eutardigrada), Zootaxa 2761 (1), pp. 34-40: 39

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http://doi.org/ 10.11646/zootaxa.2761.1.2

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gen. nov.

Tenuibiotus   gen. nov.

Genus of Macrobiotidae   characterised by claws of the tenuis   - type ( Figs. 1A View FIGURE 1 and 2A–C View FIGURE 2 ), i.e. with a stalk, a long common section in which primary and secondary branches are joined, and distal free sections of both the secondary branch (shorter than the primary) and primary branch forming almost a right angle.

The bucco-pharyngeal apparatus is of the ‘ Macrobiotus   type’. Species attributed to this group share additional characters: narrow rigid buccal tube; small buccal cavity and poorly developed buccal armature; eggs of the known species laid freely and with conical or trunco-conical processes with more or less wide basal diameter.

Type species: Macrobiotus tenuis Binda & Pilato, 1972   .

Etymology: The name refers to the type of claws ( tenuis   - type) which is the main characteristic of the new taxon.

Composition: the following species, previously ascribed to the genus Macrobiotus   , have to be transferred to the new genus: M. tenuis   , M. willardi   , M. hystricogenitus   , M. hyperonyx   , M. higginsi   , M. mongolicus   , M. bondavallii   , M. kozharai   , M. tenuiformis   , M. danilovi   , M. voronkovi   and M. ciprianoi   .

We agree with Tumanov (2005) that M. ariekammensis   ( Fig. 3C View FIGURE 3 ) and M. kirghizicus   ( Fig. 3D View FIGURE 3 ) do not have claws of tenuis   - type (their claws have primary and secondary branches joined over a much shorter distance than in the typical tenuis   - type) and therefore they cannot be ascribed to the genus Tenuibiotus   .

Unfortunately we did not have the chance to examine Macrobiotus caelicola   that shares some characters with species of the tenuis   group, but in Guil et al. (2007) Fig. 4F, the common portion of the claws of this species appears shorter than in the claws of the tenuis   - type; as a consequence, we have doubts about its attribution to the new genus Tenuibiotus   , but the problem needs further study.