Aretiana Delicado & Ramos, 2021

Delicado, Diana, Pešić, Vladimir & Ramos, Marian A., 2021, Arganiella Giusti & Pezzoli, 1980 (Caenogastropoda: Truncatelloidea: Hydrobiidae): a widespread genus or several narrow-range endemic genera?, European Journal of Taxonomy 750 (1), pp. 140-155 : 145-146

Genus Aretiana Delicado & Ramos gen. nov.

urn:lsid:zoobank.org:act:7B207B6D-47E8-4211-8139-0CF98DA353D7

Type species

Boetersiella wolfi Boeters & Glöer, 2007 .

Revised diagnosis

Shell trochiform; whorls 3.5–4.0; aperture complete, rounded; outer lip narrow, straight in lateral profile; umbilicus wide. Operculum corneous, yellowish, thin, pliable, oval to rounded, paucispiral with a central nucleus, without peg. Two pairs of basal cusps on each central radular tooth. Ctenidium well developed, with approximately 14 gill filaments. Osphradium positioned opposite to approximately the middle of the ctenidium. Stomach without gastric caecum; rectum forms a gentle U-shape in the mantle cavity. Bursa copulatrix medium-sized, pyriform, pedunculated and protruding beyond the posterior edge of the albumen gland; bursal duct shorter than bursal length; unpigmented renal oviduct that makes a complete loop over the pallial gland; one elongated or pyriform seminal receptacle arising from the renal oviduct, just above the insertion point with the bursal duct. Prostate gland bean-shaped, about twice as long as wide. Penis small and simple, gradually tapering. Nervous system unpigmented.

Etymology

The genus is named after Villa Aretiana , the Roman name of the town Aracena, which gives its name to the mountain range where the genus was found (i.e., Sierra de Aracena); gender feminine.

Remarks

Aretiana Delicado & Ramos gen. nov. can be distinguished from Arganiella as the former has a taller shell, a more oval operculum, pigmentation on the body and eyespots, fewer gill filaments, a narrower penis, a larger and pyriform bursa copulatrix located beyond the posterior edge of the albumen gland and fewer cusps on the lateral radular teeth (for comparison, see Giusti & Pezzoli 1980; Boeters & Glöer 2007; Arconada & Ramos 2007a). The new genus differs from the closely related genus Iberhoratia by its taller shell with a narrower umbilicus, the absence of lobes on the inner edge of the penis and of a proximal seminal receptacle (SR2) and presence of two pairs of basal cusps on each central radular tooth (see Arconada et al. 2007). Mean COI divergence for Aretiana Delicado & Ramos gen. nov. was 15.9% with Arganiella and 11.2% with Iberhoratia .