Doryphoribius neglectus, Pilato, Giovanni & Lisi, Oscar, 2004

Pilato, Giovanni & Lisi, Oscar, 2004, Doryphoribius neglectus sp. n. and Parascon nichollsae sp. n., new species of eutardigrades from Australia, Zootaxa 545, pp. 1-7 : 2-4

Doryphoribius neglectus sp. n. ( Fig. 1 . A­E)

Description of the holotype: Body length 308.0 µm ( Fig.1 A ) colorless, eyes not preserved (but we do no exclude their presence); cuticle smooth. Bucco­pharyngeal apparatus of Doryphoribius type ( Fig. 1 B ). Mouth anterio­ventral without peribuccal lamellae and papulae; no teeth visible in the mouth cavity (but this character needs to be confirmed); buccal tube rigid with ventral lamina; stylet supports inserted on the buccal tube at 69.9% of its length (pt = 69.9). Buccal tube 26.5 µm long, and 2.4 µm wide (pt = 9.1). Stylet furcae ( Fig. 1 B ) of a very peculiar shape, robust, triangular in shape, with the posterio­lateral processes rounded but not swollen. Pharyngeal bulb with small apophyses and two rodshaped macroplacoids, microplacoid absent. Entire row of placoids 9.4 µm long (pt = 35.5); first macroplacoid, with a central constriction, 5.5 µm long (pt = 20.8), second macroplacoid 3.7 µm long (pt = 14) without constriction.

Claws of Isohypsibius type ( Fig. 1 D,E), slender, with a very short basal portion; external claws with slightly enlarged bases; main branches with very short and thin accessory points. External and internal claws 9.2 µm (pt = 34.7) and 6.9 µm (pt = 26.0) long respectively on the first pair of legs; 9.4 µm (pt = 35.5) and 7.3 µm (pt = 27.5) respectively on the second and third pairs of legs; anterior and posterior claws on fourth pair of legs as long as the internal and, respectively, the external claws, on the second and third pairs of legs. Lunules and other cuticular thickenings absent on all legs.

Eggs unknown.

Etymology: neglectus = neglected.

Differential diagnosis: The new species differs from all species of the genus Doryphoribius in the shape of the stylet furcae and perhaps it could be ascribed to a new genus, but since we have only one specimen, we temporarily attribute it to the genus Doryphoribius . Etymology: neglectus = neglected.

Only five species of the genus Doryphoribius have unsculptured cuticle and two macroplacoids: D. evelinae ( Marcus, 1928) , D. doryphorus ( Binda & Pilato, 1969) , D. macrodon Binda, Pilato & Dastych 1980 , D. pilatoi Bertolani, 1984 and D. koreanus Moon, Kim & Bertolani, 1994 .

Besides, D. neglectus differs from D. evelinae in having legs without tubercles. It differs from D. doryphorus in having buccal tube shorter with respect to the body length (in the holotype of D. neglectus , 308 µm long, the buccal tube is 26.5 µm long (8.6 %), in specimens of D. doryphorus 202 µm long, the buccal tube is 23.7 µm long (11.7 %)), and claws with slightly shorter basal portion.

The new species differs from D. pilatoi in having the claws of the fourth pair of legs not reduced.

It differs from D. macrodon in having more slender claws with shorter basal portion, and less evident buccal armature (no teeth visible in the mouth cavity, but this character needs to be confirmed).

It differs from D. koreanus in having claws with shorter basal portion, less evident buccal armature, (no teeth visible in the mouth cavity, but this character needs to be confirmed) and lacking of lunules.

Figures

FIGURE 1. A – B, Doryphoribius neglectus sp. n.; habitus (A) and bucco­pharyngeal apparatus (B). C, Bucco­pharyngeal apparatus of Doryphoribius doryphorus. D – E, claws of the second and third pairs of legs of Doryphoribius neglectus sp. n. (D) and of the fourth pair of legs (E) (in A scale bar = 30 µm; in B, C, D and E scale bar = 20 µm).