Minibiotus taiti, Claxton, 1998

Claxton, Sandra K., 1998, A revision of the genus Minibiotus (Tardigrada: Macrobiotidae) with descriptions of eleven new species from Australia, Records of the Australian Museum 50 (2), pp. 125-160 : 131-133

Minibiotus taiti n.sp.

Figs. 3, 18b; Table 2

Type material. HOLOTYPE inAM ( AM KS41430 ): Australia, New South Wales: Ryde , 33°48'S 151°04'E, 500 m a.s.l., 16 June 1993, S.K. Claxton, foliose lichen and leaf litter on asphalt . PARATYPES (7 specimens, 3 eggs in AM [ AM KS41431-41440 ]; 31 specimens, 2 eggs in SKC): same data as holotype but collected on 3 May 1985 and 1 February 1992 .

Additional material examined. New South Wales: Appin , 34°12'S 150047'E, 29 August 1985, PD . Claxton, weft moss on rock in open sclerophyl forest, 10 specimens, 3 eggs. Sandy Hollow , 32°22'S 150034'E, 20 March 1993, S.K. Claxton, weft moss on rock in open sclerophyl forest, 22 specimens, 5 eggs. Queensland: Eumundi , 26°28'S 152°27'E, 20 December 1986, D.S. Homing, fruticose lichen on old bridge timber, wind exposed, 6 specimens, 3 eggs. Great Keppel Island , 23°10'S 150058'E, 14 July 1993, P.D. Claxton, foliose lichen on rock, wind exposed, 3 specimens, 1 egg. Australian material in SKC . NEW ZEALAND: Snares Islands, Ho Ho Creek , 23 October 1972, D.S. Homing, 2 specimens ( SA301 ). Mollymawk Bay , 30 January 1971, D.S.H., 2 specimens ( SA26 ). Seal Point , 2 March 1972, D.S.H., 2 specimens ( SA216 ). Broughton Island , 18 February 1971, D.S.H., 4 specimens ( SA60 ). ( NZM). CHINA: Quingdao, October 1994, N. Marley, moss, 6 specimens in NM. USA: Texas, Taylor County, 27 December 1989, C.W. Beasley, leaf litter on soil, 2 specimens in MUT .

Diagnosis. Smooth cuticle with no pores and granulation on all legs; 3 round macroplacoids and a distinct microplacoid; long slender claws with short, low accessory claws and smooth lunules.

Description. Body length 160-320 /lffi, colourless. Eye spots, when present, in posterior position. Cuticle smooth, patch of granulation on the outside of first three pairs of legs near claws, also on back and sides of fourth pair of legs. Buccal tube narrow (8% of buccal tube length). Stylet supports inserted at 60.3% of the buccal tube length, ventral support very short (40.3% ofbuccal tube length). Pharyngeal bulb round (25 /lffi diameter) containing large, granular apophyses, three macroplacoids and a microplacoid. Macroplacoid row short (32.1% ofbuccal tube length); first macroplacoid round but slightly elongated anteriorly where it lies under the apophysis (which is about the same size), second macroplacoid small, granular; third macroplacoid granular but with a slight caudal bulb which curves towards midline. Microplacoid distinct, lying close to third macroplacoid. Claws long and slender (fourth pair of claws is 33.2% of length of buccal tube) with refractive zone at base and with short secondary branch. Accessory claws short and lie close to main branch. Lunules smooth on all claws. Eggs colourless, round, diameter without processes 54

/lm, with processes 64 /lm. About 48 processes around circumference, about 160 in a hemisphere. Processes like thin nails, 3.2-5.4 /lID high, base diameter 1-1.5 /lID, top

diameter 2-3 /lID. Top of each process appears to have a ring of very small circles around a central pore. A membrane surrounds each process but it is not clear if this is continuous over all the processes or if it reaches the shell surface between the processes.

Etymology. The species is named after Dr N.N. Tait of Macquarie University.

Remarks. This species differs from M. intermedius described above, by having granulation around the claws, a wider buccal tube, stylet supports inserted lower down the buccal tube and by the slightly different structure of the processes of the egg. It differs from Macrobiotus acontistus De Barros, 1942 by having a microplacoid, a narrower buccal tube, macroplacoids of similar size, the second never larger than the first and by having granulation around the claws.

Habitat. The type material was found in foliose lichens and Eucalyptus nuts on asphalt in the parking lot at Macquarie University. At other sites in NSW and in Queensland the species was found in mosses and lichens in locations subject to drying and high temperatures.

Tables

Table 2. Measurements (in flm) of adults of Minibiotus taiti n.sp.

Character	No.	Range	Mean	SD	SE Holotype
bodylength	20	176-297	248	31.4	7.0	277
BTlength	20	21.6-27.6	25.2	1.6	0.4	27.0
BTwidth	20	1.6-2.4	2.0	0.2	0.04	2.2
SIlength	20	13.0-16.8	15.2	1.0	0.2	16.2
VSlength	20	8.7-11.4	10.2	0.7	0.2	10.8
PRlength	20	7.6-10.8	9.5	1.0	0.2	10.8
MPRlength	20	6.5-9.2	8.1	0.9	0.2	9.2
m 1	20	1.6-3.0	2.4	0.4	0.1	2.7
m 2	20	1.6-2.7	1.9	0.3	0.1	2.2
m 3	20	1.6-2.7	2.2	0.3	0.1	2.2
microplacoid	20	0.4-1.1	0.8	0.2	0.1	0.8
PHlength	15	23.0-30.0	26.0	2.3	0.6	27
PHwidth	15	22.0-30.0	25.0	2.2	0.6	27
clawI	20	6.5-8.1	7.2	0.4	0.1	7.6
clawII-III	20	7.0-8.7	7.7	0.4	0.1	8.1
clawIV	20	7.6-9.2	8.4	0.6	0.1	9.2