Macrobiotus garynahi, Kaczmarek, Łukasz, Michalczyk, Łukasz & Diduszko, Dawid, 2005

Kaczmarek, Łukasz, Michalczyk, Łukasz & Diduszko, Dawid, 2005, with a description of Macrobiotus garynahi sp. nov. (Eutardigrada: Macrobiotidae: richtersi group), Zootaxa 1053, pp. 35-45 : 37-43

Macrobiotus garynahi sp. nov. ( Figs 1–13 )

Material examined. 10 specimens and 11 eggs, Russia, Irkutsk Province, East Sayany Mts., ca. 700 m asl, near Lake Baikal, dark taiga, lichen from stone, together with unidentified Macrobiotus sp. (2 specimens) and Diphascon cf. pingue (1 specimen), 16.08.2004; leg. D. Diduszko.

Description. Adult (holotype): Body length 480.0. Body transparent/white, eyes absent ( Fig. 3 ). Cuticle smooth and with evident oval pores (3.0–5.0 in longer diameter) on whole cuticle. Fine but evident, regular granulation present on all legs but developed better on IV pair ( Figs 4–5 ).

Bucco­pharyngeal apparatus of Macrobiotus ­ type ( Figs 1–2 ). Mouth antero­ventral, surrounded by ring of 10 peribuccal lamellae. Oral cavity armature with three bands of teeth ( Figs 1–2 ). Teeth of first band are smaller than those of the other two bands and are in the shape of small granules. They are present in anterior portion of oral cavity just behind peribuccal lamellae and on them. This band of teeth is continuous and looks the same on all oral cavity walls. In the second band, the teeth are intermediate in size between those of the first band and those of the third band of teeth. They are in the shape of small ridges parallel to the main axis of the buccal tube (ventral teeth are little larger than dorsal). They are positioned in the posterior portion of the oral cavity just behind the ring fold and just before the third band of teeth. The second band of teeth is continuous and arranged in one row. Some of the teeth are uniform and regular, in the shape of ridges but the rest are joined one­by­one. Joined teeth are H­, V­ and W­shaped. In the third band, the teeth are larger than those in the other two rows and there are usually six. They are in the shape of transverse ridges/baffles. Teeth in this band are positioned in the rear of the oral cavity just behind the second band of teeth and just before the buccal tube opening. Usually this band is not continuous and is divided into two series: ventral and dorsal. Both series consist of one median and two lateral teeth. Dorsal teeth are more bar­shaped but the ventral are more rectangular­shaped.

Buccal tube 54.0 long and 9.0 [16.7] wide with one bend in anterior part of tube (visible in lateral view). Stylet supports inserted on buccal tube at 42.0 [77.8]. Pharyngeal bulb slightly oval with apophyses, three macroplacoids and microplacoid ( Figs 1–2 ). Pharyngeal apophyses distinct, rounded and indented posteriorly ( Fig. 2 ). First macroplacoid thinner anteriorly, 7.0 [13.0] long, second oval, 5.5 [10.2] long, both without constriction. Third macroplacoid 8.0 [14.8] long, with distinct constriction in subterminal part. Microplacoid distinct, septula­shaped (with two lateral wings) 3.5 [6.5] long ( Fig. 1 ). Macroplacoid row 24.0 [44.4] long. Placoid row 31.0 [57.4] long.

Claws of hufelandi ­ type, stout ( Figs 5–7 ). Primary branches with distinct accessory points. Lunules on all legs smooth, better developed on IV pair of legs. External (ext.) claw of I pair of legs 12.0 [22.2] long, internal (int.) 10.0 [18.5] long, II ext. 12.0 [22.2], int. 11.0 [20.4]; III ext. 11.5 [21.3], int. 10.0 [18.5]; IV posterior 12.0 [22.2], anterior 11.0 [20.4]. Bars absent but cuticular thickenings below claws present ( Fig. 3 , arrowheads).

Eggs: White/colourless, laid freely ( Figs 8–13 ). Spherical, areolated, with 10–13 processes on circumference ( Figs 8–9 ). Processes in the shape of cones terminated by caplike structures with fine, irregular indentation (sometimes caps can be split into two parts). Processes consist of double wall with transverse supporting walls forming cells visible in PCM as the reticular design (reticulation slightly elongated vertically) ( Fig. 10 ). External walls of processes smooth or slightly wrinkled (wrinkles in form of rings around a process) ( Figs 9, 11, 12 ). Internal walls strongly porous (visible in SEM only). Surface between processes areolated. Areoles (10 around each process) with smooth/wrinkled surface (without sculpturing and pores), not well visible in PCM ( Figs 9, 11, 13 ).

Remarks. Adults: Results of simple statistical analysis of measurements and pt values of selected morphological structures for nine specimens are given in Table 1 . The measurements of the smallest and largest specimen are provided in Table 2 .

Eggs: Measurements for all measurable eggs are provided in Table 3 . Processes have the same type of structure but limited variability of shapes and sizes of some characters was noted. The processes always appear as cones, but may be terminated in two ways. The most common termination is a cap­like structure, but there are also processes terminated with split caps. Also, some caps may have smooth edges instead of indentations on the circumference.

Type depositories. Holotype and 9 paratypes (4 adults and 5 eggs) are deposited in the Natural History Collections, Faculty of Biology, A. Mickiewicz University, Umultowska 89, 61–614 Poznań, Poland; 7 paratypes (4 adults and 3 eggs) are deposited in the Department of Animal Taxonomy and Ecology, A. Mickiewicz University, Poznań; 4 paratypes (1 adult and 3 eggs) are deposited in Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy.

Etymology. The name garynahi is given after a mystic monster, troll or gnome Garynah which is believed to live in the Siberian Mountains.

Differential Diagnosis. The new species is most similar to Macrobiotus vanescens Pilato et al., 1991 by the morphometric characters of adults and similar claws with narrow basal portion and M. alekseevi Tumanov, 2005 by the eggs processes appearance.

Macrobiotus garynahi sp. nov. differs from M. vanescens by the presence of larger microplacoid (3.0–4.0 in the new species and 2.68 in M. vanescens in specimen 525.0 long), shorter claws on the IV pair of legs (posterior claws11.0–16.0, anterior claws 10.5– 16.0 in the new species and posterior claws 20.36, anterior claws 19.67 in M. vanescens in specimen 525.0 long), larger eggs (96.0–132.0 (142.0–180.0 with processes) in the new species and 83–93 (117.0–125.0 with processes) in M. vanescens )), longer egg processes (18.0–30.0 in the new species and 16.0–17.0 in M. vanescens ) and the presence of cap­like structure on the top of the egg processes.

The new species differs also from M. alekseevi by the presence of evident granulation on all legs, different oral cavity armature especially in the third band of teeth (ventrolateral teeth without denticulate margin, medio­ventral tooth not divided), larger body size (380.0–720.0 in the new species and 365.8–552.0 in M. alekseevi ), slightly wider buccal tube (7.0–14.0 in the new species and 6.3–11.5 in M. alekseevi ), larger microplacoid (3.0– 4.0 in the new species and 1.9–3.0 in M. alekseevi ), larger eggs (96.0–132.0 in the new species and 59.2–82.8 in M. alekseevi ), longer egg processes (18.0–30.0 in the new species and 11.8–21.8 in M. alekseevi ), wider base of the processes (20.0–42.0 in the new species and 13.3–22.9 in M. alekseevi ) and less evident areolation on the eggs.

Claw 4 posterior (internal) 7 11.0 ­ 16.0 20.4 29.4 13.9 24.9 2.2 3.0

length

Claw 4 ­ anterior (external) length 10.5 23.3? ?

Claw 4 ­ posterior (internal) length 11.0 24.4? ?

Figures

FIGURES 1 – 2. Macrobiotus garynahi sp. nov., buccal apparatus: 1 ventral view, 2 mid section / dorsal view.

FIGURES 3 – 7. Macrobiotus garynahi sp. nov.: 3 habitus (arrowheads indicate cuticular thickenings below claws), 4 granulation on II pair of legs (arrow), 5 claws of I pair of legs with granulation on the leg (arrow), 6 claws of III pair of legs, 7 claws of IV pair of legs (PCM).

FIGURES 8 – 13. Macrobiotus garynahi sp. nov., the egg: 8 – 9 whole egg (PCM and SEM), 10 reticulation on the process (PCM), 11 single process (SEM), 12 a cap on the terminal portion of the process (SEM), 13 ­ areolation (SEM).

Tables

TABLE 1. Measurements [in µm] of selected morphological structures of specimens of Macrobiotus garynahi sp. nov. mounted in Hoyers medium (range refer to the smallest and the largest structure found among all measured specimens; N number of specimens / structured measured, SD standard deviation).

CHARACTER	N	RANGE	MEAN	SD
		µm pt	µm pt	µm pt
Body length	9	380.0 ­ 720.0 803.9 1125.0	549.2 948.7	139.3 119.8
Buccal tube length	9	45.0 ­ 66.0	57.1 ­	8.2 ­
Stylet support insertion point	9	35.0 ­ 52.0 77.8 80.4	45.1 79.0	6.6 1.0
Buccal tube external width	9	7.0 ­ 14.0 14.9 21.9	10.7 18.4	2.7 2.5
Macroplacoid 1 length	9	6.5 ­ 12.0 13.0 19.0	9.6 16.6	2.4 2.2
Macroplacoid 2 length	9	5.0 ­ 9.0 10.2 15.5	7.2 12.5	1.9 1.9
Macroplacoid 3 length Microplacoid length Macroplacoid row length	9 9 9	7.0 ­ 12.0 13.7 20.7 3.0 ­ 4.0 4.7 8.5 21.0 ­ 35.0 44.4 56.9	9.7 16.7 3.6 6.4 28.9 50.1	2.3 2.2 0.4 1.2 6.2 4.6
Placoid row length	9	26.0 ­ 45.0 55.3 70.3	36.4 63.2	8.0 5.8
Claw 1 external length	8	11.0 ­ 16.0 22.2 25.0	13.9 23.6	2.0 0.9
Claw 1 internal length	8	10.0 ­ 15.0 18.5 23.5	12.9 22.0	2.0 1.7
Claw 2 external length	9	11.0 ­ 15.0 21.2 25.5	13.2 23.3	1.6 1.3
Claw 2 internal length	9	9.0 ­ 16.0 20.0 25.0	12.7 22.2	2.2 1.7
Claw 3 external length Claw 3 internal length Claw 4 anterior (external) length	7 8 7	11.5 ­ 15.0 20.7 25.5 9.0 ­ 18.0 18.5 27.7 10.5 ­ 16.0 22.2 27.5	13.4 22.2 13.4 22.7 13.4 23.9	1.2 1.6 3.0 2.9 2.2 1.7

TABLE 2. Measurements [in µm] and pt values of selected morphological structures of the smallest and the largest measured specimens of Macrobiotus garynahi sp. nov. mounted in Hoyers medium.

CHARACTER	µm	pt	µm	pt
Body length	380.0	844.4	720.0	1125.0
Buccal tube length	45.0	­	64.0	­
Stylet support insertion point	35.0	77.8	50.0	78.1
Buccal tube external width	7.0	15.6	14.0	21.9
Macroplacoid 1 length	6.5	14.4	12.0	18.8
Macroplacoid 2 length	5.0	11.1	9.0	14.1
Macroplacoid 3 length	7.0	15.6	12.0	18.8
Microplacoid length	3.0	6.7	3.5	5.5
Macroplacoid row length	21.0	46.7	35.0	54.7
Placoid row length	26.0	57.8	45.0	70.3
Claw 1 ­ external length	?	?	16.0	25.0
Claw 1 ­ internal length	?	?	15.0	23.4
Claw 2 ­ external length	11.0	24.4	15.0	23.4
Claw 2 ­ internal length	9.0	20.0	16.0	25.0
Claw 3 ­ external length	?	?	14.0	21.9
Claw 3 ­ internal length	9.0	20.0	16.0	25.0