Laevicaspia derzhavini ( Logvinenko & Starobogatov, 1969 )

Anistratenko, Vitaliy V., Sitnikova, Tatiana Ya. & Anistratenko, Olga Yu., 2021, Holotypes for three Caspian gastropods of the family Hydrobiidae tracked down description and taxonomic interpretations, Zootaxa 5027 (3), pp. 408-416 : 414

Laevicaspia derzhavini ( Logvinenko & Starobogatov, 1969)

Fig. 3a–f

Pyrgula (Ulskia) derzhavini Logv. et Star. — Logvinenko & Starobogatov 1969: 379, fig. 367(9).

Pyrgula derzhavini Logvinenko et Starobogatov, 1968 — Kantor & Sysoev 2006: 99, pl. 45, fig. J.

? Ulskia derzhavini ( Logvinenko & Starobogatov, 1969) — Wesselingh et al. 2019: 73 .

Laevicaspia derzhavini ( Logvinenko & Starobogatov, 1969) — Anistratenko et al. 2021: 186 , fig. 19f–h.

Type material. Holotype ( ZIN 1 /534-2021) and 6 paratypes ( ZIN 2 /534-2021) derive from the same lot, labeled “40/1957” ( Tab. 1, locality 21), collected by B.M. Logvinenko off Cheleken Peninsula on 2 August 1957. Earlier we detected in the ZIN collection another six specimens ( ZIN 3 /534-2021) collected from this locality (21) determined as “ Caspia derzhavini ”. Since the material formed a single lot that was labelled by Starobogatov himself, we considered it as the type material ( Anistratenko et al. 2021).

Further 21 paratypes ( ZIN 4 /534-2021–10/534-2021) recently traced are stored in seven separate tubes, labels only marked with the number of station and year of collection ( Table 1) collected in various parts of the South Caspian Sea ( Fig. 1 , localities 14, 17, 18, 20, 38, 39) between 26 June 1956 and 4 August 1957 .

Type locality. Originally given as “Middle and Southern Caspian Sea between 45–81 m water depth” without further details ( Logvinenko & Starobogatov 1969). The holotype was collected in the Caspian Sea near Cheleken Peninsula, Turkmenistan ( Table 1, locality 21) from 55 m depth .

Remarks. This species was originally described as Pyrgula (Ulskia) derzhavini and has previously been classified within the Caspiinae ( Logvinenko & Starobogatov 1969, Kantor & Sysoev 2006). The shells of this species have a very slender elongate shape, and the protoconch ornamentation differs greatly from that found in Caspiinae , showing irregular spiral threads on a smooth surface. Shape and protoconch features strongly remind of Laevicaspia ( Neubauer et al. 2018) . According to the holotype shell characteristics we here confirm its position in the genus Laevicaspia , subfamily Pyrgulinae , as proposed previously ( Anistratenko et al. 2021).

Distribution. Endemic to the Caspian Sea, only known from 7 localities (see above) in the South Basins from depths of 16 and 107 m.

Figures

FIGURE 1. Geographic overview of the study area, with the indication of sampling points and places mentioned in the text (modified from Wesselingh et al. 2019). See Table 1 for details.

FIGURE 3. (a, b) Laevicaspia derzhavini (Logvinenko & Starobogatov, 1969), holotype, locality 21 (ZIN 1/534-2021). (c–f) L. derzhavini, three paratypes, locality 21 (ZIN 2/534-2021 (c, d) and ZIN 3/534-2021 (e, f)). Images of one specimen (e and f) reproduced after Anistratenko et al. 2021. Scale bar = 1 mm.