Chaetonotus (Hystricochaetonotus) iratus
Reference
Rataj Križanová F. & Vďačný P. (2022) A huge undescribed diversity of the subgenus Hystricochaetonotus (Gastrotricha, Chaetonotidae, Chaetonotus) in Central Europe. European Journal of Taxonomy 840: 1-93. https://doi.org/10.5852/ejt.2022.840.1941
Chaetonotus (Hystricochaetonotus) iratus, schematic drawings. (A) Dorsal overview showing the scale and spine pattern. (B, D) Lateral and dorsal views of a head scale. (C, F) Lateral and dorsal views of a trunk scale. (E) Dorsolateral head scale. (G) Ventrolateral trunk scale. (H) Furca branches scale. (I) Detail showing the mouth region. (J) Internal morphology. The structure of the cerebral ganglion was observed only in a single specimen. Scale bar: 30 μm.
© 2022 Rataj Križanová F. & Vďačný P. This picture is licensed under a CC BY-NC-ND 4.0 license.
Secondary structure of the 18S rRNA molecule of Chaetonotus (Hystricochaetonotus) iratus. The single diagnostic molecular autapomorphy is situated in helix 44 (red arrow). The reference 18S secondary structure map of Saccharomyces cerevisiae (inset) is from apollo.chemistry.gatech.edu/RibosomeGallery.
© 2022 Rataj Križanová F. & Vďačný P. This picture is licensed under a CC BY-NC-ND 4.0 license.
Secondary structure of the first two domains of the 28S rRNA molecule of Chaetonotus (Hystricochaetonotus) iratus. Diagnostic molecular autapomorphies are marked by red arrows. The reference 28S secondary structure map of Saccharomyces cerevisiae (inset) is from apollo.chemistry.gatech.edu/RibosomeGallery.
© 2022 Rataj Križanová F. & Vďačný P. This picture is licensed under a CC BY-NC-ND 4.0 license.
Morphological diagnosis
Body elongated and about 124 μm long. Head slightly wider than neck, separated from trunk by an inconspicuous neck constriction. Cephalion, epipleurae, and hypopleurae clearly demarcated. Trunk widest at ca U61, gradually tapers towards furca base (U82). Mouth ventral, one central cuticular tooth. Hypostomium bears two parallel, horizontally arranged lamellae accompanied by tear-shaped protuberances. Pharynx without dilatations. Intestine straight, with a marked anterior section. Scales spined, three-lobed, slightly overlapping, distributed in about 12 columns, 22 scales per column. Scales and spines increase gradually in size in a posterior direction. Dorsal surface covered by scales from posterior end of cephalion (ca U4) to furca branches (ca U83). Furca branches slightly shorter than adhesive tubes, lateral margins more or less straight, furcal indentation V-shaped, adhesive tubes comparatively short.
Molecular diagnosis
18S rRNA gene: 1716 C.
ITS2: 38 C, 61 T, 67 C, 68 A, 85 T, 86 G, 91 C, 103 C, 113 T, 114 A, 124 A, 129 G, 155 C.
28S rRNA gene: 465 C, 656 T, 674 G.
Cytochrome c oxidase subunit I (codon ordinal numbers are followed by the corresponding span of nucleotide positions in parentheses): 123 (367‒369) GTG, 159 (475‒477) CGG, 186 (556‒558) CTA, 216 (646‒648) ATC.
Type material
A DNA sample of the holotype specimen STV 65 has been deposited in the Natural History Museum, Vajanského nábrežie 2, 810 06 Bratislava, Slovakia (ID Collection Code 01427609).
Type locality
Shallow section of the River Váh near the village of Stankovany, Veľká Fatra Mts, Slovakia, 49°08′26.3″ N, 19°10′14.6″ E.