taxonID	type	description	language	source
A742A85EFFFEFFC8FF00FCDEFB3152BD.taxon	description	Family: Macrobiotidae Thulin, 1928 Genus: Mesobiotus Vecchi et al., 2016. Mesobiotus silesiacus sp. nov. Warguła, Stec, Rutkowski, Kayastha, Gierlasiński & Kaczmarek. (Figs. 1, 2 and 3; Tables 2 – 3). Material examined: Seven animals, two eggs mounted on microscope slides in Hoyer’s medium and one specimen processed for DNA sequencing. Type locality: 49 ° 43 ' 33.4 " N, 18 ° 44 ' 18.6 " E; 502 m asl: Jasieniowa Mountain, Goleszów, Upper Silesia, Poland, moss growing on rock in closed quarry, coll. Tomasz Rutkowski and Grzegorz Gierlasiński, 28 September 2022. Etymology: Species name refers to the area where new species was discovered (Silesia, southern Poland). Type depositories: Slide JAS. 21.4 / 3 with one paratype, slide JAS. 21.4 / 4 with one egg and slide JAS. 21.4 / 6 with exoskeleton of sequenced individual are deposited at the Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Sławkowska 17, 31 - 016, Kraków, Poland, whereas the holotype and five paratypes (slide: JAS. 21.1 / 3) and one egg (JAS. 21.4 / 5) are deposited at the Department of Animal Taxonomy and Ecology, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 6, Poznań, Poland. Animals (measurements and statistics in Table 2): Body white in living specimens and transparent after fixation in Hoyer’s medium (Fig. 1 A). Eyes absent in specimens fixed in Hoyer’s medium. Body and leg cuticle smooth, i. e., without pores, granulation, sculpturing or tubercles. Mouth antero-ventral. Bucco-pharyngeal apparatus of the Macrobiotus type (Figs. 1 B – D), with ventral lamina and ten small peribuccal lamellae. The oral cavity armature well developed and consists of three bands of teeth (Figs. 2 A – C). The first band of teeth is composed of numerous small granules arranged in several discrete rows located anteriorly in the oral cavity, just behind the bases of the peribuccal lamellae (Fig. 2 A, filled flat arrowhead). The second band of teeth is located between the ring fold and the third band of teeth and is composed of ridges parallel to the main axis of the buccal tube that are larger than those in the first band (Figs. 2 A – C, empty flat arrowhead). The teeth of the third band are located within the posterior portion of the oral cavity, between the second band of teeth and the opening of the buccal tube (Figs. 2 A – C, filled indented arrowhead). The third band of teeth is discontinuous and divided into a dorsal and ventral portion. Under PCM, dorsal and ventral series of teeth are composed of two lateral and one median transverse ridges / crests (Figs. 2 A – C). Pharyngeal bulb oval (Fig. 1 B – C), with triangular apophyses, three rod-shaped macroplacoids, and a large, elongated microplacoid placed close to the third macroplacoid (Fig. 1 B). The macroplacoid length sequence is 2 <3 <1. The first macroplacoid is anteriorly narrowed, and the third has a clearly defined subterminal constriction (Fig. 1 C – D, filled arrow). Claws of the Mesobiotus type, with a peduncle connecting the claw to the lunula, a basal septum, and well-developed accessory points situated parallel to the primary branch (Figs. 2 D – E). Lunulae under claws I – III smooth (Fig. 2 D, white filled arrow) and those under claws IV slightly dentate (Fig. 2 E, empty arrow). A single continuous cuticular bar (Fig. 2 D, black filled arrow) with shadowed extensions narrowing toward double muscle attachments is present below claws I – III (Fig. 2 D, empty indented arrowhead), while a horseshoe-shaped structure connects the anterior and posterior lunulae on claws IV (Fig. 2 E). Eggs (measurements and statistics in Table 3): White, laid free, spherical in shape (Fig. 3 A) and with cones with long slender endings which sometimes terminate with one to few filaments (Figs. 3 C – D, filled arrow). Egg surface between processes without areolation. In PCM the egg surface between processes seems to be smooth (Figs. 3 A – B). The labyrinthine layer is visible under PCM as a reticulum in the process walls, with various mesh size uniformly distributed within the process walls (Figs. 3 C – D). In PCM, the flexible upper portions of the egg processes are smooth i. e. not covered with granules (Figs. 3 C – D).	en	Warguła, Jędrzej, Stec, Daniel, Rutkowski, Tomasz, Gierlasiński, Grzegorz, Kayastha, Pushpalata, Kaczmarek, Łukasz (2025): An integrative description of a new species of the genus Mesobiotus (Tardigrada: Eutardigrada: Macrobiotidae) from Poland. Organisms Diversity & Evolution 25 (1): 189-202, DOI: 10.1007/s13127-025-00671-4, URL: https://doi.org/10.1007/s13127-025-00671-4
