Milnesium dornensis Roszkowska & Kaczmarek, 2015, sp. nov.
Creators: name: Roszkowska, Daniel Adrian Ciobanu Milena
name: Kaczmarek, Łukasz
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Phyllodocida
Aphroditidae
Milnesium
Milnesium dornensis

description: Milnesium dornensis sp. nov.
http://www.tardigrada.net/register/0018.htm (Figs 1 – 14, Tables 1 – 2)
Material examined: Holotype (female), 46 paratypes (36 females and 10 males) and five exuvia with 18 smooth eggs.
Description of the adults (Figures 1 – 2) (measurements in µm, pt ratios and statistics in Tables 1 – 2): Body brownish (in live specimens) or transparent (after fixation in Hoyer’s medium). Eyes present or absent (visible before and after mounting; 68% of fixed specimens had eyes). Cuticle sculptured with pseudopores (0.5–0.7 Μm in diameter in females and 0.3–0.5 Μm in males), not arranged in bands, sparsely distributed and not forming a reticular design. Under PCM these pseudopores are visible as light spots, placing the species within the granulatum group (Figs 4 and 6). On the dorsal side, in the caudal region, an area similar to plate structures is visible (Fig. 8). These plates are visible only in a few females and at present it is hard to evaluate their taxonomic significance. Six peribuccal papillae and six peribuccal lamellae around the mouth opening present (Figs 3 and 5). Two cephalic papillae, positioned laterally.
Bucco-pharyngeal apparatus of the Milnesium type (Figs 3 and 5). Buccal tube slightly funnel-shaped, wider anteriorly (posterior diameter on average 90% of the anterior diameter). Pharyngeal bulb elongated, pear-shaped and without placoids or septulum. Claws of the Milnesium type, slender (Figs 7, 9 and 11 – 13). Primary claws on all legs are simple, unbranched with small accessory points detaching from the branch at its greatest curvature (Figs 10 and 14). Secondary claws on all legs with rounded basal thickenings (lunules) (sometimes barely visible) (Figs 9 and 13). Secondary claws on all legs with three branches (claw configuration: [3-3]-[3-3]) (Figs 7, 9 and 12–13), with the exception of the sexually dimorphic modified claws of the males of first pair of legs (Fig. 11). Single, long and transverse cuticular bars under claws I – III present (Figs 7 and 12). In males, the cuticular bars on first pair of legs distinctly wider than those on legs II–III.
Eggs: Oval, smooth and deposited in exuvium as in all other known Milnesium species.
Locus typicus: 47°20'13.7''N, 25°19'38.8''E; 968 m asl: Romania, Suceava County, Vatra Dornei town, lichen (Usnea sp.) from tree (Picea abies L., H. Karst.).
Etymology: Milnesium dornensis is named after Vatra Dornei, the town, where the species was found.
Type depositories: Holotype (female; slide: VD-7), 36 paratypes (29 females and seven males; slides VD1, VD2, VD10, VD11, VD13, VD14) and one exuvium with eggs (slide VD10) are preserved at the Department of Animal Taxonomy and Ecology, Adam Mickiewicz University in Poznań, Umultowska 89, 61–614 Poznań, Poland. Additionally, three paratypes (females) (slides: VD3, VD4, VD5) are deposited at the Natural History Museum of “Alexandru Ioan Cuza” University from Iaşi, Romania (Bd. Independenţei No.16, 700101) and eight paratypes (five females and three males; slides: VD6, VD8, VD9, VD12) are deposited at the Department of Zoology, Comenius University, Bratislava, Slovakia.
Differential diagnosis (for adult females). Based on having a sculptured dorsal cuticle, Milnesium dornensis sp. nov. belongs to the granulatum group (Michalczyk et al. 2012a,b). The new species is most similar to M. alabamae Wallendorf & Miller, 2009, M. beasleyi Kaczmarek et al., 2012 a, M. granulatum (Ramazzotti, 1962), M. katarzynae Kaczmarek et al., 2004, M. krzysztofi Kaczmarek & Michalczyk, 2007, M. lagniappe Meyer et al., 2013 and M. reticulatum Pilato et al., 2002, but it differs from:
M. alabamae by: different dorsal sculpture (pseudopores not arranged in bands, sparsely distributed and not forming a reticular design in M. dornensis sp. nov. vs pseudopores arranged in bands (especially in caudal region), densely distributed and forming a reticular design in M. alabamae), the presence of accessory points on primary branches of claws and a larger pt of the body length ([1,496–1,986] in M. dornensis sp. nov. vs [821–1,388] in M. alabamae).
M. beasleyi by: a different claw configuration ([3-3]-[3-3] in M. dornensis sp. nov. vs [2-3]-[3-2] in M. beasleyi), the presence of rounded basal thickenings under secondary branches of claws (sometimes poorly visible), larger pt of peribuccal papillae length ([22.0–28.3] in M. dornensis sp. nov. vs [19.6–21.3] in M. beasleyi), larger pt of the anterior buccal tube width ([42.5–54.5] in M. dornensis sp. nov. vs [35.3–41.8] in M. beasleyi) larger pt of the anterior primary branch of the claw IV ([57.9–67.0] in M. dornensis sp. nov. vs [53.1–57.4] in M. beasleyi).
M. granulatum by: a different dorsal sculpture (pseudopores not arranged in bands, sparsely distributed and not forming reticular design in M. dornensis sp. nov. vs pseudopores densely distributed and forming a reticular design in M. granulatum) different lengths of claws on legs IV (see Table 1 below and Table 2 in Bartels et al. (2014) for the exact differences in dimensions of the claws).
M. katarzynae by: a different claw configuration ([3-3]-[3-3] in M. dornensis sp. nov. vs [2-2]-[2-2] in M. katarzynae), different dorsal sculpture (pseudopores not arranged in bands, sparsely distributed and not forming a reticular design in M. dornensis sp. nov. vs pseudopores densely distributed and forming a reticular design in M. katarzynae), a larger body size (384 – 874 µm in M. dornensis sp. nov. vs 285.0 – 294.5 µm in M. katarzynae), the stylet supports inserted in a more anterior position ([64.3–68.1] in M. dornensis sp. nov. vs [73.3–78.3] in M. katarzynae), a different buccal tube standard width (9.4–22.7 Μm in M. dornensis sp. nov. vs 6.6–7.6 Μm in M. katarzynae) and a different pt of buccal tube standard width ([37.8–51.6] in M. dornensis sp. nov. vs [21.7–26.6] in M. katarzynae).
M. krzysztofi by: a different claw configuration ([3-3]-[3-3] in M. dornensis sp. nov. vs [2-3]-[3-2] in M. krzysztofi), a different dorsal sculpture (pseudopores not arranged in bands, sparsely distributed and not forming a reticular design in M. dornensis sp. nov. vs pseudopores densely distributed and forming a reticular design in M. krzysztofi), larger pt of the body length ([1,496–1,968] in M. dornensis sp. nov. vs [1,262–1,425] in M. krzysztofi) larger internal/anterior spurs of claws I – IV (I: 4.3 – 6.3 Μm [10.6–14.4]; II: 4.1 – 6.5 Μm [10.3–14.6]; III: 3.5 – 6.2 Μm [11.3–14.3]; IV: 3.5 – 6.6 Μm claws [12.1–17.9] in M. dornensis sp. nov. vs I: 2.5 – 2.5Μm [10.1–10.1]; II: 2.5 – 2.8 Μm [? –9.8]; ca. III: 3.4 Μm [ca. 10.8]; IV: 2.7–3.2 Μm [8.0–10.1] in M. krzysztofi).
M. lagniappe by: a different claw configuration ([3-3]-[3-3] in M. dornensis sp. nov. vs [2-3]-[3-2] in M. lagniappe), a different dorsal sculpture (pseudopores not arranged in bands, sparsely distributed and not forming a reticular design in M. dornensis sp. nov. vs nine dorsal and lateral sculptured bands bearing a reticulated pattern of polygons in M. lagniappe), having six peribuccal lamellae (four in M. lagniappe), the stylet supports inserted in a more anterior position ([64.3–68.1] in M. dornensis sp. nov. vs [69.7–73.4] in M. lagniappe), smaller pt of width of the buccal tube ([42.5–54.5], [37.8–51.6], [34.8–51.8] anterior, standard and posterior respectively in M. dornensis sp. nov. vs [68.0–77.5], [63.4–77.9], [61.8–70.8] anterior, standard and posterior respectively in M. lagniappe), a smaller buccal tube standard width/length ratio (38% – 52% in M. dornensis sp. nov. vs 63% – 78% in M. lagniappe) and a smaller pt of the external base+secondary branch of claws I ([34.2–40.9] in M. dornensis sp. nov. vs [41.6–51.0] in M. lagniappe).
M. reticulatum by: a different claw configuration ([3-3]-[3-3] in M. dornensis sp. nov. vs [2-3]-[3-2] in M. reticulatum), a different dorsal sculpture (pseudopores not arranged in bands, sparsely distributed and not forming a reticular design in M. dornensis sp. nov. vs pseudopores arranged in nine sculptured bands, forming a reticular design in M. reticulatum), absence of cuticular gibbosities, having six peribuccal lamellae (four in M. reticulatum), the stylet supports inserted in a more anterior position ([64.3–68.1] in M. dornensis sp. nov. vs [68.5–69.8] in M. reticulatum) and larger claws I – IV (see Table 1 below and Table 2 in Pilato et al. (2002) for the exact differences in dimensions of the claws).
description: Published as part of Roszkowska, Daniel Adrian Ciobanu Milena & Kaczmarek, Łukasz, 2015, Two new tardigrade species from Romania (Eutardigrada: Milnesiidae, Macrobiotidae), with some remarks on secondary sex characters in Milnesium dornensis sp. nov., pp. 542-564 in Zootaxa 3941 (4) on pages 544-550, DOI: 10.11646/zootaxa.3941.4.4, http://zenodo.org/record/233659