Platicrista horribilis, a new species of Tardigrada (Eutardigrada: Hypsibiidae) from Mongolia Author Kaczmarek Author Michalczyk text Zootaxa 2003 132 1 8 journal article 51377 10.5281/zenodo.156806 be3c09fe-62e3-4d14-b779-b82923082dba 1175­5326 156806 Platicrista horribilis sp. nov. ( Figs 1­5 ) Description Holotype : Total body length 720 m ( Fig. 1 ). Body white or transparent. Cuticle smooth. Eyes absent. Buccopharyngeal tube 76 m long and 3 m wide. Apophyses for insertion of stylet muscles very wide, with a flat ridge. Drop­like thickening between buccal and pharyngeal tube absent. Buccal tube 39 m long. Pharyngeal tube with spiral thickening 37 m long, ending (on dorsal or ventral view) with semilunar structures ( 4 m long). In pharynx, between end of pharyngeal tube and the first macroplacoid two very slender cuticular bars directed forward ( 5 m long). Stylet supports inserted 1 m above upper limit of pharyngeal tube. Pharyngeal bulb pear­shaped, 77 m long and 37 m wide, containing two slender, lancet­shaped macroplacoids with irregularly undulated edges. First macroplacoid 14 m , second 33 m long; both 1 m wide. Macroplacoid row 48 m long. Septulae and microplacoid absent ( Figs 2­3 ). Claws of Hypsibius ­ type ; on I pair of legs: external (primary branch: 30 m , secondary: 13 m ), internal (pb.: 17 m , sb.: 10 m ); II: ext. (pb.: 33 m , sb.: 15 m ), int. (pb.: 20 m , sb.: 12 m ); III: ext. (pb.: 34 m , sb.: 14 m ), int. (pb.: 22 m , sb.: 12 m ); VI: ext. (pb.: 34 m , sb.: 16 m ), int. (pb.: 23 m , sb.: 14 m ). Primary branches of internal and external claws with two accessory points. On IV pair of legs lunules with fine teeth. Cuticular bars on legs absent ( Figs 4­5 ). Eggs unknown. Measurements of some structures of holotype and two paratypes are shown in Tab. 1 . Remarks There is visible fine granulation on IV pair of legs in paratype 1. Very slender cuticular bars are orientated backwards in paratype 1 (probably caused by preparation); in paratype 2 only one of these structures is visible. In some cases the teeth on lunules may resemble knobs. Type locality Northern Mongolia ; Archangaj Ajmag, Tehijn Cagan Nuur National Park; Tarbagataj Mts.; 2700 m ; mosses from rocks; VII 2000 ; leg. oe. Kaczmarek. FIGURE 1. Platicrista horribilis sp. nov. 1, habitus (drawn from Phase Contrast Microscope). FIGURES 2­3. Platicrista horribilis sp. nov. 2­3, buccal apparatus (2, middle section); (3, ventral section) (drawn from Phase Contrast Microscope). TABLE 1. Measurements of specimens and selected morphological structures of Platicrista horribilis sp. nov. , mounted in Hoyer’s medium. CHARACTER HOLOTYPE PARATYPE 1 PARATYPE 2 AVERAGE CHARACTER HOLOTYPE PARATYPE 1 PARATYPE 2 AVERAGE Material examined
[m] pt [m] pt [m] pt m] pt
Body length 720 1826,5 397 1227,9 343 1388,5 486,6 1480,97
Buccopharyngeal tube length 76 194,0 60 185,3 51 207,7 62,5 195,65
Buccal tube length 39 100,0 32 100,0 25 100,0 32,1 100,00
Pharyngeal tube length 37 94,0 28 85,3 27 107,7 30,4 95,65
Level of stylet support insertion 38 97,6 point 31 95,6 24 97,2 31,1 96,78
Buccal tube internal width 3 7,2 3 8,8 3 11,5 2,9 9,20
Semilunar structures at the end 4 10,8 of buccal tube length 4 12,5 5 21,2 4,5 14,83
1 macroplacoid length 14 36,1 8 24,3 7 27,9 9,7 29,43
2 macroplacoid length 33 84,3 18 55,9 19 76,9 23,4 72,38
Macroplacoid row length 48 121,7 29 89,7 27 109,6 34,7 107,00
Pharyngeal slender bar length 5 12,0 3 9,6 4 14,4 3,8 12,01
Pharyngeal bulb length 77 196,4 58 179,4 56 225,0 63,7 200,27
Pharyngeal bulb width 37 92,8 26 80,9 30 123,1 31,0 98,91
Primary branch of external 30 77,1 claw I length 19 58,8 13 53,8 20,9 63,26
Secondary branch of external 13 33,7 claw I length 9 26,5 10 42,3 10,8 34,17
Primary branch of internal claw 17 43,4 I length 13 41,2 11 46,2 13,9 43,57
Secondary branch of internal 10 24,1 claw I length 8 23,5 5 19,2 7,3 22,29
Primary branch of external 33 84,3 claw II length 27 82,4 21 84,6 26,9 83,77
Secondary branch of external 15 38,6 claw II length 10 29,4 10 38,5 11,4 35,48
Primary branch of internal claw 20 50,6 14 44,1 10 42,3 14,9 45,68
II length
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TABLE 1. ( continued).
[m] pt [m] pt [m] pt m] pt
Secondary branch of internal claw II length 12 31,3 10 29,4 9 34,6 10,1 31,78
Main branch of external claw III length 34 86,7 24 73,5 23 92,3 26,9 84,19
Secondary branch of external claw III length 14 36,1 10 32,4 9 34,6 11,1 34,37
Main branch of internal claw III length 22 55,4 14 44,1 13 53,8 16,5 51,13
Secondary branch of internal claw III length 12 31,3 10 29,4 8 30,8 9,8 30,50
Main branch of external claw IV length 34 86,7 21 64,7 23 92,3 26,0 81,25
Secondary branch of external claw IV length 16 41,0 12 38,2 11 46,2 13,3 41,78
Main branch of internal claw IV length 23 57,8 14 44,1 14 57,7 17,1 53,21
Secondary branch of internal claw IV length 14 36,1 10 32,4 10 38,5 11,4 35,65
Etymology
The name ‘ horribilis’ refers to the big, horrifying, robust claws and very large size of
specimens.
Holotype is preserved at the Zoological Museum of Jagiellonian University, ul. Ingardena 6, 30­060 Kraków, Poland ; paratype 1 is preserved at the Department of Animal Taxonomy and Ecology, A. Mickiewicz University, Poznañ; paratype 2 is preserved in the collection of oe. Michalczyk (Jagiellonian University). Differential diagnosis Platicrista horribilis is similar to P. affine (Mihelcic, 1951) and P. angustata (Murray, 1905) however, it is easily distinguishable by the presence of teeth on the lunules of the IV pair of legs (it was not mentioned in the description by Ramazzotti & Maucci (1983) , however, the dilated bases are smooth in the drawings). The new species differs from P. itaquasconoide (Durante & Maucci, 1975) by lacking the microplacoid, small basal spur of the claw on the IV pair of legs and by having a narrower buccal tube ( 8 m in P. itaquasconoide ). Platicrista horribilis differs from P. cheleusis Kathman, 1990 by lacking the polygonal pattern on cuticle and cuticular bars on legs.