Haplomacrobiotus utahensis, Pilato, Giovanni & Beasley, Clark, 2005

Pilato, Giovanni & Beasley, Clark, 2005, Haplomacrobiotus utahensis new species of Calohypsibiidae (Eutardigrada) from North America, Zootaxa 879, pp. 1-7: 2-6

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http://doi.org/ 10.5281/zenodo.273218

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Haplomacrobiotus utahensis

sp. n.

Haplomacrobiotus utahensis   sp. n.

Material examined: Utah, Canyonlands National Park in Moab, 20 specimens (holotype and 19 paratypes) in two samples (collection dates: June 2003, June 2004).

Type repository: Holotype and three paratypes are deposited in the Maria Grazia Binda and Giovanni Pilato collection; 16 paratypes in the collection of Clark Beasley.

. Description of the holotype: Body length 417 m, colourless, eye spots present, cuticle smooth without pores. Bucco­pharyngeal apparatus with rigid buccal tube and ventral lamina ( Figs. 1 View FIGURE 1 A; 2 A, B; 3). Mouth antero­ventral rounded by six well evident peribuccal lobes ( Fig. 1 View FIGURE 1 B). Peribuccal lamellae absent. Peribuccal papulae present, these structures different in size ( Fig. 3 View FIGURE 3 B) and probably, as reported by Pilato (1993) for H. hermosillensis   , some of them are forked. A crown of fine teeth is present in the anterior portion of the buccal cavity ( Fig. 2 View FIGURE 2 B). Posterior portion of the buccal cavity without teeth but two laterodorsal and two ventro­lateral transversal ridges present. Medio­dorsal and a medio­ventral ridges seem to be absent. Buccal tube 43.1 m long and 6 m width (pt = 13.9). Stylet supports inserted on the buccal tube at 67.4 % of its length (pt = 67.4). Pharyngeal bulb with apophyses and three rod­shaped macroplacoids ( Figs 1 View FIGURE 1 A; 2 A, B; 3 A); microplacoid absent. First macroplacoid 5.0 µm long (pt = 11.6), second 4.6 µm (pt = 10.7), third 5.6 µm (pt = 13.0); entire row of macroplacoids 16.6 µm long (pt = 38.5). All legs with two single, thin and small claws ( Figs 2 View FIGURE 2 C, D). Internal claw on the second and third pairs of legs 5.2 µm long (pt = 12.1), external claw on the same pairs of legs 5.7 µm long (pt = 13.2); anterior claw on the hind legs 5.8 µm long (pt = 13.4), posterior claw of the same pair of legs 6.4 µm long (pt = 14.8). Lacking lunules and cuticular thickenings on the legs. Eggs unknown.

Etymology: The name utahensis   is derived from the state of Utah, where the specimens were collected.

Differential Diagnosis: Haplomacrobiotus utahensis   sp. n. is the second species of the genus; it is similar to H. hermosillensis   in many characters, but differs from it in the some features: more evident peribuccal lobes ( Figs. 1 View FIGURE 1 B and 4 D); wider buccal tube ( Table 1); thinner and shorter claws ( Figs. 2 View FIGURE 2 C, D and 4 A, B, C; Table 1); first macroplacoid different in shape (in H. hermosillensis   the first macroplacoid with a longer, thin anterior portion ( Fig. 4 View FIGURE 4 B) and therefore in some focal positions that macroplacoid appears shorter than the second ( Fig. 4 View FIGURE 4 A), but in another focal position the true length of that placoid appears evident ( Fig. 4 View FIGURE 4 B). In H. utahensis   sp. n. the anterior portion of the first placoid is shorter and therefore the true length of that macroplacoid is better evident ( Figs. 1 View FIGURE 1 A; 2 A). For this reason, when specimens of H. hermosillensis   and H. utahensis   sp. n. are compared not very carefully, placoids of the same length may seem to be, in some focus positions, different in length.

Remarks: We emphasize that peribuccal lobes in H. hermosillensis   were considered absent by Schuster et al. (1980; page 292, Table 1), but Fig. 4 View FIGURE 4 D demonstrates that they are present. They are less visible when the buccal tube is retracted. The peribuccal papulae, as in H. hermosillensis ( Pilato, 1993)   may have different dimensions ( Fig. 3 View FIGURE 3 B) from one another; it is not clear whether they are forked or not. The characters of Haplomacrobiotus utahensis   sp. n, particularly the presence, the number and the symmetry of peribuccal lobes and peribuccal papulae confirm the opinion (expressed by Pilato since 1969) that the genus Haplomacrobiotus   must be ascribed to the family Calohypsibiidae   .