Pruvotia cf. sopita ( Pruvot, 1891 )

Cobo, M. Carmen, Farris, William J. & Kocot, Kevin M., 2024, New data on the biodiversity of Solenogastres (Mollusca, Aplacophora) in the Mediterranean Sea: findings from the program “ Our Planet Reviewed ” Corsica 2019 - 2022, Zoosystema 46 (21), pp. 543-576 : 570

Pruvotia cf. sopita ( Pruvot, 1891)

Proneomenia sopita Pruvot, 1891: 721 .

Pruvotia sopita – Thiele 1913: 273.

MATERIAL EXAMINED. — Corsica (France) • 1 specimen (used for sclerite preparations and DNA extraction); CORSICABENTHOS 2 ( Table 2 ); 80 m depth; MNHN-IM-2019-1744; GenBank: OR456214; OR458908 (1 microscope slide with sclerites, anterior and posterior regions preserved in 95% ethanol).

DESCRIPTION

Small white animal (7 × 1-1.5mm) with the anterior region slightly wider than the posterior one, rounded ends ( Fig. 4C ). With hollow acicular sclerites (80-100 × 6-8 µm) ( Fig. 8K, L ). Sclerites barely protruding from cuticle. Found on Sertularella sp. ( Hydrozoa).

REMARKS

The tentative identification of the specimen as Pruvotia sopita is based on its external appearance and the way it is attached to the Sertularella sp. colony. The habitus of the Corsica specimen, characterized by a small, white body, and the absence of coiling around its host but rather attachment solely at the anterior region of the body to the hydrozoan branches, closely mirrors the description provided by Pruvot (1891) for Pruvotia sopita . This resemblance is further sustained by our own observations of this species (Castro-Claros et al. pers. comm.). Histology was not performed due to the specimen’s small size and the fact that it was damaged. Consequently, our identification relies on these characteristic external features. Interestingly, our phylogenetic analysis recovers the Corsica specimen well within Pruvotinidae with strong support (bootstrap support: 92%; Fig. 2 ). Confirmation of the identification of this specimen as Pruvotia sopita would necessitate a reevaluation of not only Pruvotia ’s classification within Rhopalomeniidae but also of the monophyly of Pruvotinidae with respect to Rhopalomeniidae .

Figures

FIG. 4. — Habitus of A, Tegulaherpia cf. myodoryata (photo of the living animal – MNHN-IM-2019-16176); A’, Tegulaherpia cf. myodoryata (photo of the preserved specimen – MNHN-IM-2019-16176); B, Eleutheromenia sierra (Pruvot, 1890) (photo of the preserved specimen – MNHN-IM-2019-1749); C, Pruvotia cf. sopita (photo of the preserved specimen – MNHN-IM-2019-1744 – on Sertularella sp.); D, Unciherpia hirsuta García-Alvarez, Urgorri & Salvini-Plawen, 2001 (photo of the living animal – MNHN-IM-2019-18279); E, Simrothiella margaritacea (Koren & Danielssen,1877) (photo of the preserved specimen – MNHN-IM-2019-18280). Scale bars 1 mm. Symbols: arrow, copulatory stylets; stars, anterior end of the animals.

FIG. 8. — SEM images of the sclerites of A-G, Pruvotina impexa (Pruvot, 1890): A, general view of the sclerites in the dorsal body region (MNHN-IM-2019-18281); B, acicular sclerites and scales of the pedal groove (arrow) in the ventral region of the body (MNHN-IM-2019-18281); C, general view of the sclerites in the dorsal body region (MNHN-IM-2019-1746); D, two types of hook-shaped sclerites (star, long distal region of the hook; dot, short distal region of the hook) (MNHN- IM-2019-1746); E, hook-shaped sclerites with long distal region of the hook (star) and the serrated sclerites (encircled) (MNHN-IM-2019-18281); F, hook-shaped sclerites with short distal region of the hook (MNHN-IM-2019-18281); G, hook-shaped sclerites with long distal region of the hook (MNHN-IM-2019-18281); H-J, Pruvotina impexa (MNHN-IM-2019-16179): H, general view of the sclerites in the dorsal region of the body; I, hook-shaped sclerite; J, scales of the pedal groove; K, L, acicular sclerites of Pruvotia cf. sopita (MNHN-IM-2019-1744). Scale bars: 20 µm.

FIG. 2. — Maximum likelihood phylogenetic reconstruction based on COI. MNHN CORSICABENTHOS specimens are shaded with colors corresponding to those used in Fig 1. BOLD (ALPNB #s) and NCBI accession numbers precede species names for publicly available sequences and both NCBI accession numbers and museum catalog numbers precede the species names for the Corsica specimens. Symbols: *, the taxa considered as reference sequences based on Kocot et al. (2019); gray blocks, species delimitation results according to Assemble Species by Automatic Partitioning (ASAP, Puillandre et al. 2021).