Macrobiotus barabanovi, Tumanov, Denis V., 2005

Tumanov, Denis V., 2005, Two new species of Macrobiotus (Eutardigrada, Macrobiotidae) from Tien Shan (Kirghizia), with notes on Macrobiotus tenuis group, Zootaxa 1043, pp. 33-46 : 34-38

Macrobiotus barabanovi sp. nov. ( Figs. 1–17 , Table 1 )

Type specimens. Holotype: slide number 197(17) (sex indet.), collected by Dr. A.V. Barabanov (Zoological Institute Russian Academy of Sciences, St. Petersburg) 17.08.1998, Kirghizia, Chui Area. Paratypes: slide numbers 195(1, 2, 4, 5, 6), 197(16, 18, 20) from the same locality. Holotype and paratypes are preserved at the Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia. One paratype (slide number 195(1)) preserved in the collection of Binda and Pilato (Department of Animal Biology, University of Catania, Italy). Type locality: Kirghizia, Chui Area, northern slope of Kirghizian ridge, Turakaiyn canyon, vicinity of Turakaiyn village, near 2000 m a.s.l., moss from soil. Twenty adult and juveniles and 15 eggs (2 with developed embryos) were found.

Etymology. This species is dedicated to Dr. A.V. Barabanov, who kindly collected the material for me in Kirghizia.

Description. Body long and relatively plump (body length of adult animals 452.2– 591.9 m) ( Figs. 1 , 9 ). Color white (colourless). With little granular eye spots (in some specimens eyespots dissolved during the slide preparation). Cuticle smooth, only with well defined small areas of granulation on the ventral side, similar to those described by Maucci (1973) in Macrobiotus tenuis . Typical distribution of these areas is the following: one area between legs I, two areas aligned in a transverse row between legs II and between legs III, three areas aligned transversally between first three pairs of legs, two rows of three areas between the 3rd and the 4th pairs of legs and a pair of areas laterally to anus. Fine dot­like sculpture on legs IV. Bucco­pharyngeal apparatus of Macrobiotus type ( Figs. 2 , 10 ) (for all dimensions see Table 1 ). Buccal cavity with ten peribuccal lamellae, a posterior crown of triangular teeth and a system of three dorsal and three ventral transverse ridges dorsally and ventrally, consisting of medial and paired lateral crests ( Figs. 3, 4 , 11, 12 ). Large specimens with anterior band of minute dots. Ventral strengthening bar relatively long exceeding half of the length of the buccal tube. Pharyngeal bulb suboval, with well developed apophyses, three macroplacoids and elongated microplacoid. Third macroplacoid with a distinct pre­terminal constriction.

pt of external claw length, leg IV 59.4 51.7 59.4 60.1 (51.7–66.7) 1.22 Ss = distance from cephalic end of buccal tube to insertion point of stylet supports.

Supplementary measurements for holotype: length of strengthening bar on buccal tube: above 32.6 m, lunules on claws of the fourth pair of legs: 5.9 x 11.1 m

Claws long, thin, with flexible main branches (degree of bending of the distal part of main branches could vary much even within the same leg), minute stalk, poorly marked distal part of the basal portion and short common tract ( Figs. 5, 6 , 13, 14 ). Primary and secondary branches diverge near 1/3 of claw length, main branches with well developed accessory points. Claws of fourth pair of legs longer than claws of first three pairs of legs. All claws with large lunules, especially on legs IV. Lunules of legs IV with distinct marginal teeth, lunules of legs I–III with slightly waved edges. Lunules of legs IV with clearly darkened medial area, the same area is scarcely visible in lunules of legs I–III. Legs I–III with long curved band of thickened cuticle below claw bases.

Eggs laid free, spherical in shape, white, and ornamented with bulbous processes with attenuated apical parts clearly septate and sometimes bent downward ( Figs. 7, 8 , 15, 16, 17 ). Processes with developed polygonal to roundish reticulation. Processes bases with small projections. Egg shell between processes with scarcely visible radial ridges. Usually egg surface poorly visible, covered with debris particles. Diameter of eggs (without processes): 81.2–91.3 m; height of processes (about 20 on the circumference of egg): 11.0– 17.2 m, their basal diameter: 8.5–12.7 m.

Remarks. Macrobiotus barabanovi sp. nov. belongs to the harmsworthi group. It could be easily distinguished from the majority of species of this group in having noticeably longer claws. Within the harmsworthi group, the only species with similar claw morphology is M. altitudinalis Biserov, 1997 (1998) . Macrobiotus barabanovi sp. nov. differs from this species in having longer claws of the hind legs (pt value 52.5–66.7 in M. barabanovi sp. nov. and 47.2 (mean pt) in M. altitudinalis ), relatively shorter secondary branches of claws of the hind legs, lunules of the legs IV with marginal teeth and darkened zone, eggs with smaller and more numerous processes.

Figures

FIGURES 1 – 8. Macrobiotus barabanovi sp. nov. 1 – habitus, 2 – bucco­pharyngeal apparatus, ventral, 3 – buccal armature, dorsal, 4 – buccal armature, ventral, 5 – claws of the II pair of legs, 6 – claws of the IV pair of legs, 7 – general appearance of the egg, 8 – part of the egg surface (3, 4, 6 – holotype; 1, 2 – paratypes, 5 – specimen from the type series).

FIGURES 9 – 17. Macrobiotus barabanovi sp. nov. 9 – habitus, 10 – bucco­pharyngeal apparatus, ventral, 11 – buccal armature, dorsal, 12 – buccal armature, ventral, 13 – claws of the II pair of legs (arrow points to the cuticular thickening), 14 – claws of the IV pair of legs, 15 – general appearance of the egg, 16 – part of the egg surface, 17 – egg processes (phase contrast; 9 – 12, 14 – holotype, 13 – paratype).

Tables

TABLE 1. Summary of morphometric data for Macrobiotus barabanovi sp. nov. (n = 16).

Character	Holotype	Smallest specimen	Largest specimen	Mean (Range)	Standard error
Body length (m) Buccal tube length (m)	591.9 51.1	452.2 44.4	591.9 51.1	514.3 (452.2–591.9) 47.9 (39.2–54.8)	10.42 1.09
Ss (m)	39.2	33.7	39.2	36.4 (29.6–42.2)	0.87
pt Ss Outer buccal tube width (m) pt of outer buccal tube width	76.8 8.1 15.9	75.8 6.8 15.3	76.8 8.1 15.9	76.1 (75.0–77.1) 7.4 (5.9–9.6) 15.5 (13.6–17.6)	0.16 0.27 0.27
Placoid row length (m)	26.6	25.2	26.6	27.4 (22.2–32.6)	0.86
pt of placoid row length Macroplacoid row length (m) pt of macroplacoid row length	52.2 22.2 43.5	56.7 19.6 44.2	52.2 22.2 43.5	57.1 (52.2–61.4) 21.9 (17.0–26.6) 45.7 (42.6–50.0)	0.66 0.71 0.59
1st macroplacoid length (m)	7.0	5.9	7.0	6.9 (4.4–8.9)	0.31
pt of 1st macroplacoid length 2nd macroplacoid length (m) pt of 2nd macroplacoid length	13.8 5.2 10.1	13.3 4.8 10.8	13.8 5.2 10.1	14.4 (11.3–16.4) 5.6 (4.4–6.7) 11.6 (9.8–13.6)	0.37 0.21 0.30
3rd macroplacoid length (m)	7.4	6.7	7.4	6.9 (4.8–8.1)	0.22
pt of 3rd macroplacoid length Microplacoid length (m) pt of microplacoid length External claw length, leg I (m)	14.5 3.7 7.2 17.0	15.0 4.4 10.0 14.8	14.5 3.7 7.2 17.0	14.3 (12.3–15.7) 4.2 (3.0–5.2) 8.8 (7.2–10.3) 18.5 (14.8–22.2)	0.21 0.16 0.27 0.57
pt of external claw length, leg I External claw length, leg III (m) pt of external claw length, leg III External claw length, leg IV (m)	33.3 – – 30.3	33.3 16.3 36.7 22.9	33.3 – – 30.3	38.8 (32.3–44.1) 20.5 (16.3–25.2) 43.5 (36.7–51.7) 28.7 (22.9–32.9)	0.99 0.79 1.45 0.75