Minibiotus keppelensis, 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: 143-148

publication ID

http://doi.org/ 10.3853/j.0067-1975.50.1998.1276

publication LSID

lsid:zoobank.org:pub:4C7B3B68-1D65-4506-8B7F-08C2CF4C55AC

DOI

http://doi.org/10.5281/zenodo.4657340

persistent identifier

http://treatment.plazi.org/id/59798784-0D46-3637-14E0-15C7A41E81D1

treatment provided by

Felipe

scientific name

Minibiotus keppelensis
status

n.sp.

Minibiotus keppelensis   n.sp.

Figs. 10, 19c; Table 9 View Table 9

Type material. HOLOTYPE in AM ( AM KS41495): Australia, Queensland: Great Keppel Island , 23°10'S 150059'E, 14 July 1993, P.D. Claxton   . PARATYPES (4 specimens, 2 eggs in AM [ AM KS41496 - KS41501]; 13 specimens, 4 eggs in SKC) same data as holotype   .

Diagnosis. Cuticle smooth with 10transverse rows of round pores and granulation on all legs; 3 small round macroplacoids and anindistinct microplacoid; robust claws with long, low accessory claws and smooth lunules.

Description. Body length 180-287 /lm, colourless, some specimens with red pigment granules. Eye spots large, in posterior position. Cuticle smooth with. round (1 /lm) pores arranged in ten distinct transverse bands around body and on legs. Fine granulation on top and both sides of claws on first three pairs of legs and on back and sides of fourth pair of legs. Buccal tube very narrow (5.8% of buccal tube length). Stylet supports inserted at 60.6% of the buccal tube length, ventral support short (40.4% of buccal tube length). Pharyngeal bulb oval to round (27x30 /lm), placoids in anterior half; containing three macroplacoids and a microplacoid. Macroplacoid row short (26.6% of buccal tube length); macroplacoids small, granular as are apophyses which are about the same size as the first macroplacoid. First macroplacoid round, slightly elongated anteriorly where it lies beneath the apophysis; second macroplacoid granular smaller than other two; third macroplacoid granular but with slight caudal bulb which curves towards midline. Microplacoid small, indistinct and lies very close to third macroplacoid. Claws robust (fourth pair of claws is 30.1% of buccal tube length) with large refractive zone at base and with long secondary branch; long accessory claws lie close to main branch on all claws. Lunules small, smooth on all claws.

Eggs colourless, round, diameter without processes 45-55 /lm, with processes 65-85 /lm. Eleven processes around circumference and 24 in hemisphere. Processes short cones with pointed apices 11-16 /lm high, base diameter 9-12 /lm and 4-6 /lm-apart. Base of each process surrounded by about ten pores. Membrane around each process reaching half way up the side and apparently supported in between processes by struts (4 /lm high) so that the shell surface appears dotted.

Etymology. The species is named after the type locality, Great Keppel Island.

Remarks. The eggprocesses ofthis species are very similar to those of M. maculartus   but the adult differs from that species by having rows of large pores around the body.

Habitat. The species was found in foliose lichen on rock and in crustose lichen on a dead tree in open woodland.

Minibiotus asteris   n.sp.

Figs. 11 View Figure 11 , 19d View Figure 19 ; Table 10 View Table 10

Type material. HOLOTYPE in AM ( AM KS41502): Australia, Tasmania: O'Neill's Creek, Mount Roland Protected Area , 41°29'S 146°15'E, 680 m a.s.l., 21 May 1996, A. Moscal GoogleMaps   . PARATYPES (5 specimens, 3 eggs in AM [ AM KS41503 - KS4151 O]; 80 specimens, 17 eggs in SKC) same data as holotype GoogleMaps   .

Additional material examined. AUSTRALIA TASMANIA: Mount Montgomery 41°09'S 146°47'E, 470 m, 20 October 1994, A. Moscal, moss on rock in low woodland, 11 specimens in SKC GoogleMaps   . Hartz Mountains, 43°25'S 146°47'E, 4 December 1988, A.J. Downing, moss on mudstone in Eucalyptus   / Myrtle forest, 6 specimens, 3 eggs in SKC GoogleMaps   . VICTORIA: Melba Gully, Otway Ranges , 38°40'S 143°20'E, 4 May 1997, S.K. Claxton, leafy liverwort, moss and lichen on fallen branches in Nothofagus   forest, 33 specimens, 2 eggs ( SKC) GoogleMaps   . MACQUARIE ISLAND: Scobie Lake   , 400 m, 9 December 1977, D.S. Homing, 26 specimens. Gadget's Gully   , 220 m, 25 November 1977, D.S.H., 17 specimens. Lusitania Bay   , 400 m, 1 December 1977, D.S.H., 7 specimens. Mount Hamilton summit   , 433 m, 17 January 1978, D.S.H., 8 specimens. Mount Waite summit   , 452 m, 29 December 1977, D.S.H., 11 specimens. Mount Fletcher summit   , 428 m, 17 February 1978, D.S.H., 8 specimens. All Macquarie Island specimens in WM   . NEW ZEALAND, SOUTH ISLAND: Temple Basin Lower Ski Huts, Arthur's Pass National Park , 19 May 1970, D.S. Homing, 2 specimens ( NZI86, 188). Pegley Flat, Arthur's Pass National Park , 18 May 1970, D.S.H., 1 specimen ( NZI70). Fox Glacier Valley , 28 March 1970, D.S.H., 3 specimens (NZ23)   in NZM.

Diagnosis. Cuticle smooth with irregularly shaped pores over the whole cuticle and granulation on fourth pair of legs only; 3 small round macroplacoids and a distinct microplacoid; short, robust claws with high accessory claws and smooth lunules.

Description. Body length 128-361 /illl, colourless. Eye spots in posterior position. Cuticle over the whole body is covered with small round (0.5--0.7 /illl) pores; larger pores (about 2 /illl) with irregular shape rare but more common towards the rump. Fine granulation around claws on fourth pair of legs only. Buccal tube narrow (8% of buccal tube length). Stylet supports inserted at 63.8% of buccal tube length, ventral support short (44.8% of length of buccal tube). Pharyngeal bulb round (26 /lm diameter) containing well-developed granular apophyses, three macroplacoids and a microplacoid. Macroplacoid row short (30% of buccal tube length); macroplacoids equal in size; firstmacroplacoid granular, lying close to apophysis and partly obscured by it; second macroplacoid granular as is third which has a slight bulb at the caudal end that curves towards the midline. Microplacoid short, distinct and lies close to third macroplacoid. Claws robust (fourth pair of claws is 28% of buccal tube length) with smallrefractive zone at base and long secondary branch; accessory claws short and rising well clear of main branch. Lunules small and smooth on all claws.

Eggs colourless, round, diameter without processes 54- 67 /lm, with processes 64-85 /illl. 20-28 processes around circumference, 75-90 in ahemisphere. Processes like those

of Macrobiotus hufelandi   but with distal disk consisting of about six (up to eight) distinct arms like those of a starfish. Process height 5-10 /illl, base diameter 4.3-7.0 /lm and disk diameter 4.3-5.4 /lm. Processes are 2-4 /illl apart. 12-14 small pores around the base of each process. Egg shell surface smooth or lightly striated.

Etymology. Latin aster with masculine ending is, star, describes the appearance of the distal end of the egg processes.

Remarks. This species is probably most closely related to Macrobiotus allani Murray, 1913   as far as is possible to tellfrom the original description. It differs from that species by having eyes, pores in the cuticle, a strong microplacoid and by the nature and number of disk arms on the egg processes.

Habitat. At the type locality the species was found in mosses and liverworts on soil and rocks on a northwest gully slope in a wet Eucalyptus delegatensis   forest.

Minibiotus milleri   n.sp.

Figs. 12, 16b, 1ge; Table 11 View Table 11

Type material. HOLOTYPE in AM ( AM KS41599): Australia, New South Wales: New England National Park , 30030'S 152°24'E, 1450 m a.s.l., 18 December 1994, S.K. Claxton   . PARATYPES (7 specimens, 4 eggs in AM [ AM KS41600 - KS41608]; 56 specimens, 4 eggs in SKC) same data as holotype but some also collected on 20 April 1995 and 7 January 1996   .

Additional material examined. NEW SOUTH WALES: Cambewarra Mountain , 34°48'S 150035'E, 625 m, 9 May 1993, S.K. Claxton, moss and lichen on rocks and trees in cool temperate rainforest, 14 specimens in SKC   .

Diagnosis. Smooth cuticle with fine granulation near claws, long bean-shaped macroplacoids and a distinct microplacoid; robust claws with short, high accessory claws and smooth lunules.

Description. Body length 149-398 /lm, colourless. Eye spots in the posterior position consisting of large granules.

Cuticle smooth, fine granulation around claws on all legs. Oral cavity long with single tooth ventrally just above stylet sheaths in some larger specimens. Buccal tube narrow (pt 9.7); stylet supports inserted at 73% of buccal tube length; ventral support very short (pt 36.4). Pharynx round (27 /lm diameter) containing small apophyses, three macroplacoids and a microplacoid. Macroplacoid row long (37%

of buccal tube length); first macroplacoid smallest, somewhat pear-shaped, lying close to apophysis and partly obscured by it; second granular, slightly longer than first; third longest. Microplacoid long, distinct, lying close to third macroplacoid. Claws robust (fourth pair of claws is

26.5% of buccal tube length) with long secondary branch, well divided. Round refractive zone at base of claws well developed. Accessory claws short, raised high above main branch. Lunules on first three pairs of legs very small, smooth; on fourth pair smooth.

Eggs round, diameter without processes 68-74 /llll, with processes 90-98 /lm. 20-30 processes around circumference, 80-120 in hemisphere. Processes long cones tapering to blunt tip, rarely bifurcate, lower part of each cone indented and enclosed in membrane. Tapering portion above withrough surface which appears as transverse lines. Process height 10-14 /lm, base diameter 3 /lm arranged evenly about 3 /llll apart. Shell surface faintly striated.

Etymology. The species is named after Dr William R. Miller, friend and colleague.

Remarks. This species is similar to M. hufelandioides   and M. aquatilis   in having a long macroplacoid row, stylet supports inserted a long way down the buccal tube and no bend in the tube as it enters the pharynx but may be distinguished from these species by its very short ventral support.

Habitat. At the type locality, specimens were recovered from moss on rock, moss and lichen on tree trunks and branches in cool temperate rainforest and Banksia collina   thickets.

Table 9. Measurements (in flm) of adults of Minibiotus keppelensis n.sp.

Character No. Range Mean SD SEHolotype
bodylength 12 200-287 259.4 25.4 7.3 270
BTlength 12 24.9-28.4 26.9 1.2 0.3 27.0
BTwidth 12 1.4-1.7 1.6 0.08 0.02 1.5
SIlength 12 15.1-17.3 16.3 0.8 0.2 16.2
VSlength 12 9.7-11.9 10.9 0.7 0.2 10.8
PRlength 12 7.6-8.7 8.1 0.4 0.1 8.1
MPRlength 12 7.0-7.6 7.2 0.2 0.07 7.0
ml 12 1.6-2.7 2.2 0.3 0.08 2.2
m 2 12 1.6-2.2 1.8 0.2 0.06 1.9
m 3 12 1.6-2.2 2.0 0.3 0.08 2.2
microplacoid 12 0.5-0.8 0.6 0.1 0.03 0.5
PHlength 11 24.0-30.0 26.7 2.2 0.7 27.0
PHwidth 11 23.0-31.0 27.6 2.9 0.9 30.0
clawI 12 6.0-7.0 6.7 0.4 0.1 7.0
clawII-III 12 6.5-7.6 7.3 0.4 0.1 7.6
clawIV 12 7.0-8.6 8.1 0.6 0.2 8.6

Table 10. Measurements (in Ilm) of adults of Minibiotus asteris n.sp.

Character No. Range Mean SD SE Holotype
bodylength 20 155-368 259.7 62.8 14.0 274
BTlength 20 21.6-30.8 26.7 3.0 0.7 28.1
BTwidth 20 1.6-2.8 2.1 0.3 0.07 2.2
SIlength 20 13.5-19.5 17.0 2.0 0.5 18.1
VSlength 20 9.7-14.1 12.0 1.4 0.3 12.4
PRlength 20 7.0-11.9 9.4 1.4 0.3 9.2
MPRlength 20 6.0-10.3 8.0 1.2 0.3 8.1
ml 20 1.6-3.2 2.4 0.5 0.1 2.4
m 2 20 1.6-2.7 2.2 0.4 0.09 2.4
m 3 20 1.6-2.7 2.2 0.4 0.09 2.4
microplacoid 20 0.7-1.4 1.1 0.2 0.04 0.8
PHlength 20 22.0-33.0 26.7 3.5 0.8 27.0
PHwidth 20 22.0-36.0 26.5 3.6 0.8 27.0
clawI 20 4.9-7.6 6.3 0.9 0.2 7.0
clawII-III 20 5.4-8.2 6.9 0.9 0.2 7.6
clawIV 20 6.0-8.9 7.5 1.0 0.2 8.1

Table 11. Measurements (in flm) of adults of Minibiotus milleri n.sp.

Character No. Range Mean SD SE Holotype
bodylength 20 182-398 272.6 60.2 13.5 349
BTlength 20 24.3-35.1 29.1 3.3 0.7 31.9
BTwidth 20 2.3-3.5 2.8 0.4 0.09 3.2
SIlengtb 20 17.3-26.0 21.2 2.5 0.6 23.0
VSlength 20 8.7-12.7 10.6 1.3 0.3 11.9
PRlength 20 10.8-15.7 12.9 1.5 0.3 14.1
MPRlength 20 8.7-13.0 10.8 1.3 0.3 11.4
m 1 20 2.2-3.2 2.7 0.3 0.07 3.0
m2 20 2.4-3.5 2.9 0.3 0.07 3.2
m 3 20 2.7-4.1 3.4 0.5 0.1 3.5
microplacoid 20 0.8-1.9 1.4 0.3 0.07 1.6
PHlength 20 23.0-35.0 27.7 2.8 0.6 29.0
PHwidtb 20 23.0-33.0 26.8 2.7 0.6 27.0
clawI 20 4.9-7.6 6.4 0.9 0.2 7.0
clawII-I1I 20 5.4-8.7 7.0 0.9 0.2 7.6
clawIV 20 6.5-9.7 7.7 1.0 0.2 8.7
AM

Australian Museum