Potamides caspius Andrussow, 1902

Harzhauser, Mathias, Guzhov, Aleksandr & Landau, Bernard, 2023, A revision and nomenclator of the Cainozoic mudwhelks (Mollusca: Caenogastropoda: Batillariidae, Potamididae) of the Paratethys Sea (Europe, Asia), Zootaxa 5272 (1), pp. 1-241 : 60-65

Potamides caspius Andrussow, 1902

Figs 4A–J, 5A–H, 6

Potamides disjunctoides Sinz. — Andrussow 1902: 53, pl. 1, fig. 4 [non Potamides disjunctoides (Sinzow, 1897) ].

* Potamides caspius nov. sp. — Andrussow 1902: 55, 124, pl. 1, figs 5–18a.

[ Potamides caspius ] var. sulacensis — Andrussow 1902: 57, pl. 1, fig. 10.

[ Potamides caspius ] var. pyrguloides — Andrussow 1902: 57, pl. 1, fig. 11.

ebersini A.A. Ali-Zade, 1967 . E 1 –E 2. Potamides caspius Andrussow, 1902 , Danata ( Turkmenistan), Late Pliocene/Pleistocene, Akchagylian, syntype of Cerithium danatense A.A. Ali-Zade, 1967 . F. Potamides caspius Andrussow,1902 , Palantekyan Mountain

Ridge ( Azerbaijan), Late Pliocene / Pleistocene, Akchagylian, holotype of Cerithium carum A.A. Ali-Zade & Petrova in A.A .

Ali-Zade, 1969. G 1 –G 2. Potamides caspius Andrussow, 1902 , Naftalan ( Azerbaijan), Late Pliocene/Pleistocene, Akchagylian, holotype of Cerithium cordatum A.A. Ali-Zade & Kabakova in A.A. Ali-Zade, 1969. H. Potamides caspius Andrussow, 1902 ,

Naftalan ( Azerbaijan), Late Pliocene / Pleistocene, Akchagylian, holotype of Cerithium modicum A.A. Ali-Zade & Kabakova in

A.A. Ali-Zade, 1969. I. Potamides caspius Andrussow, 1902 , Naftalan ( Azerbaijan), Late Pliocene/Pleistocene, Akchagylian,

paratype of Cerithium modicum A.A. Ali-Zade & Kabakova in A.A. Ali-Zade, 1969. J. Potamides caspius Andrussow, 1902 ,

Naftalan ( Azerbaijan), Late Pliocene / Pleistocene, Akchagylian, holotype of Cerithium kambai A.A. Ali-Zade & Kabakova in

A.A. Ali-Zade, 1969.

lectotype of Cerithium aktschagylicum A.A. Ali-Zade, 1967 . B 1 –B 2. Potamides caspius Andrussow, 1902 , Taribani Steppe area ( Georgia), Late Pliocene/Pleistocene, Akchagylian, lectotype of Potamides taribanicus Ali-Zade, 1940 . C 1 –C 2. Potamides caspius Andrussow, 1902 , Kura and Iora rivers interfluve ( Azerbaijan), Late Pliocene/Pleistocene, Akchagylian, lectotype of

Potamides comroicus Ali-Zade, 1940 . D 1 –D 2. Potamides caspius Andrussow, 1902 , Palantekyan Mountain Ridge ( Azerbaijan), Late Pliocene/Pleistocene, Akchagylian, holotype of Cerithium bellum A.A. Ali-Zade & Petrova in A.A. Ali-Zade, 1969.

E 1 –E 2. Potamides caspius Andrussow, 1902 , Naftalan ( Azerbaijan), Late Pliocene/Pleistocene, Akchagylian, lectotype of Potamides kolesnikowi Ali-Zade, 1940 . F 1 –F 2. Potamides caspius Andrussow, 1902 , Naftalan ( Azerbaijan), Late Pliocene/ Pleistocene, Akchagylian, lectotype of Potamides deformatus Ali-Zade, 1940 . G. Potamides caspius Andrussow, 1902 , Danata

( Turkmenistan), Late Pliocene/Pleistocene, Akchagylian, paratype of Cerithium jumudicum A.A. Ali-Zade, 1967 . H. Potamides caspius Andrussow, 1902 , Qazanbulaq ( Azerbaijan), Late Pliocene/Pleistocene, Akchagylian, paratype of Cerithium kuraense

A.A. Ali-Zade & Kabakova in A.A. Ali-Zade, 1969.

[ Potamides caspius ] var. rotundispira — Andrussow 1902: 58, pl. 1, figs 12–15.

[ Potamides caspius ] var. transversa — Andrussow 1902: 57, pl. 1, figs 16–17.

[ Potamides caspius ] var. zonophora — Andrussow 1902: 58.

Potamides caspius Andr. — Goloubiatnikow 1902: 190.

[ Potamides caspius Andr. ] var. pyrguloides Andr. — Goloubiatnikow 1902: 190.

[ Potamides caspius Andr. ] var. sulacensis Andr. — Goloubiatnikow 1902: 190.

[ Potamides caspius Andr. ] var. transversa Andr. — Goloubiatnikow 1902: 190.

Potamides caspius Andrus. — K.A. Ali-Zade 1932: 16, pl. 1, figs 9–28.

Potamides caspius Andrus. —Davidaschvili 1932: 20, pl. 4, figs 13–14.

Potamides caspius Andrus. var. pyrguloides Andrus. —Davidaschvili 1932: 21, pl. 4, fig. 21.

Potamides caspius Andrus. var. rotundispira Andrus. —Davidaschvili 1932: 23, pl. 4, figs 15–18.

Potamides caspius Andrus. var. transversa Andrus. —Davidaschvili 1932: 22, pl. 4, figs 19–21.

Potamides caspius Andrus. var. sulacensis Andrus. —Davidaschvili 1932: 22, pl. 4, fig. 22.

Potamides caspius Andrus. —Bogatschev 1932: 82, pl. 10, fig. 19.

Potamides caspius Andrus. —K.A. Ali-Zade 1936: 13, pl. 1, figs 10–22.

Potamides caspius Andrus. —K.A. Ali-Zade 1936: 13, pl. 1, figs 23–27.

Potamides taribanicus n. sp. —K.A. Ali-Zade 1940: 35, pl. 1, figs 1–3.

Potamides comroicus n. sp. —K.A. Ali-Zade 1940: 37, pl. 1, figs 4–8.

Potamides comroicus Alz. var. tuberculata n. var. —K.A. Ali-Zade 1940: 37, pl. 1, figs 9–10.

Potamides kolesnikowi n. sp. —K.A. Ali-Zade 1940: 39, pl. 1, figs 20–24.

Potamides deformatus n. sp. —K.A. Ali-Zade 1940: 41, pl. 1, figs 25–27.

Potamides sumbarensis nov. sp. — Kolesnikov 1950: 93, pl. 12, figs 1 – 3.

Potamides eldaricus nov. sp. — Kolesnikov 1950: 94, pl. 12, figs 4–5.

Potamides (Inderia) caspius Andrussow — Kolesnikov 1950: 96, pl. 12, figs 6–9.

Potamides (Inderia) caspius Andrussow var. rotundispira Andrussow — Kolesnikov 1950: 97, pl. 12, figs 10–12.

Potamides (Inderia) caspius Andrussow var. pyrguloides Andrussow — Kolesnikov 1950: 98, pl. 12, figs 13–15.

Potamides (Inderia) caspius Andrussow var. sulacensis Andrussow — Kolesnikov 1950: 99, pl. 12, figs 16–18.

Potamides (Inderia) caspius Andrussow var. transversa Andrussow — Kolesnikov 1950: 100, pl. 12, figs 19–21.

Potamides caspius Andrus. —K.A. Ali-Zade 1954: 283, pl. 12, figs 1–4.

Potamides caspius var. rotundispira Andrus. —K.A. Ali-Zade 1954: 284, pl. 12, figs 5–6.

Potamides caspius var. pyrguloides Andrus. —K.A. Ali-Zade 1954: 285, pl. 12, figs 7–8.

Potamides caspius var. sulacensis Andrus. —K.A. Ali-Zade 1954: 286, pl. 12, figs 9–10.

Potamides caspius var. transversa Andrus. —K.A. Ali-Zade 1954: 287, pl. 12, figs 11–12.

Potamides taribanicus Alz. —K.A. Ali-Zade 1954: 287, pl. 12, figs 13–15.

Potamides comroicus Alz. —K.A. Ali-Zade 1954: 288, pl. 12, figs 16–19.

Potamides comroicus var. tuberculata Alz. —K.A. Ali-Zade 1954: 289, pl. 12, figs 20–21.

Potamides kolesnikowi Alz. —K.A. Ali-Zade 1954: 291, pl. 12, fig. 29.

Potamides deformatus Alz. —K.A. Ali-Zade 1954: 291, pl. 12, figs 30–34.

Potamides deformatus Alz. —K.A. Ali-Zade 1954: 291, pl. 12, figs 30–34.

Potamides caspius Andrus. —K.A. Ali-Zade et al. 1957: 86, pl. 7, figs 1–8.

Potamides taribanicus Alz. —K.A. Ali-Zade et al. 1957: 88, pl. 7, figs 9–11.

Cerithium (Potamides) sumbaricum (Koles.) —A.A. Ali-Zade 1967: 200, pl. 74, figs 1–2.

Cerithium (Potamides) eldaricum (Koles.) —A.A. Ali-Zade 1967: 201, pl. 74, figs 4–5.

Cerithium aktschagylicum nov. sp. —A.A. Ali-Zade 1967: 202, pl. 74, figs 7–11.

Cerithium danatense nov. sp. —A.A. Ali-Zade 1967: 203, pl. 75, figs 1–3.

Cerithium (Potamides) comroicum (Alz.) —A.A. Ali-Zade 1967: 203, pl. 75, figs 5–6.

Cerithium ebersini nov. sp. —A.A. Ali-Zade 1967: 204, pl. 75, figs 7–8.

Cerithium (Potamides) pyrguloidum (Andrus.) —A.A. Ali-Zade 1967: 205, pl. 75, figs 9–13.

Cerithium (Potamides) caspium (Andrussov) — Ali-Zade 1967: 206, pl. 76, figs 2–13.

Cerithium kovalevskii nov. sp. — A.A. Ali-Zade 1967: 208, pl. 77, figs 1–5.

Cerithium (Potamides) kolesnikovi [sic] (Alz.)—A.A. Ali-Zade 1967: 208, pl. 77, fig. 6.

Cerithium jumudicum nov. sp. —A.A. Ali-Zade 1967: 209, pl. 77, figs 7–12.

Cerithium caspium (Andrussov) —A.A. Ali-Zade 1969: 139, pl. 45, figs 1–3.

Cerithium pyrguloidum (Andrussov) —A.A. Ali-Zade 1969: 141, pl. 45, fig. 4.

Cerithium aktschagylicum A. Ali-Zade —A.A. Ali-Zade 1969: 142, pl. 45, fig. 5.

Cerithium cordatum A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 143, pl. 45, fig. 6.

Cerithium danatense A. Ali-Zade —A.A. Ali-Zade 1969: 143, pl. 75, figs 7–8.

Cerithium comroicum (Alz.) —A.A. Ali-Zade 1969: 144, pl. 46, figs 1–2.

Cerithium modicum A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 144, pl. 45, figs 10–12.

Cerithium taribanicum (Alz.) —A.A. Ali-Zade 1969: 145, pl. 46, figs 3–4.

Cerithium sumbaricum (Kolesnikov) —A.A. Ali-Zade 1969: 147, pl. 46, figs 7–9.

Cerithium carum A. Ali-Zade et Petrova n. sp. —A.A. Ali-Zade 1969: 148, pl. 46, fig. 10.

Cerithium eldaricum (Kolesnikov) —A.A. Ali-Zade 1969: 148, pl. 47, figs 1–2.

Cerithium deformatum (Alz.) —A.A. A.A. Ali-Zade 1969: 150, pl. 47, figs 4–5.

Cerithium kolesnikowi (Alz.) —A.A. Ali-Zade 1969: 151, pl. 47, figs 6–7.

Cerithium rectum A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 152, pl. 47, fig. 8 [non Vinassa de Regny, 1898]. Cerithium jumudicum A. Ali-Zade —A.A. Ali-Zade 1969: 152: pl. 47, figs 9–10.

Cerithium kuraense A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 153, pl. 48, figs 1–2.

Cerithium tichomirovi A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 154, pl. 48, figs 5–6.

Cerithium kambai A. Ali-Zade et Kabakova n. sp. — Ali-Zade 1969: 154, pl. 48, figs 7–8.

Cerithium naphtalanicum A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 155, pl. 48, figs 9–10.

Bogatschevia bogatschevi A. Ali-Zade et Kabakova n. sp. —A.A. Ali-Zade 1969: 156, pl. 49, fig. 1.

Potamides caspius var. rotundispira Andrussow, 1902 — Volkova 1974: 89, pl. 38, fig. 10.

Potamides eldaricus Kolesnikov, 1950 — Volkova 1974: 90, pl. 38, fig. 11.

Potamides eldaricus Koles. — Dzhikiya 1977: 118, pl. 10, figs 4–6.

Potamides sumbarensis Koles. — Dzhikiya 1977: 117, pl. 10, figs 1–3.

P [otamides]. ( Ptychopotamides ?) sumbarensis (Koles.) — Nevesskaja et al. 2006: 351.

non Cerithium caspium Andr. — Simionescu & Barbu 1940: 81, pl. 1, figs 24–26 [= Potamides disjunctus (J. de C. Sowerby, 1832) ].

non Pirenella caspia (Andrussow) — Wenz 1942: 66, pl. 24, figs 375–378 [= Potamides taitboutii (d’Orbigny, 1844) ].

non Potamides caspius Andrus. — Dzhikiya 1977: 118, pl. 10, figs 7–11 [= Theodisca azerbajdjanica ( Ali-Zade, 1940) ].

Type material. Lectotype designated herein: Nr. 2/358, SL: 22.2 mm, MD: 8.9 mm, illustrated in Andrussow (1902, pl. 1, fig. 6), Figs 4A 1 –A 2. Paralectotypes: Nr. 3/358, SL: 16.2 mm, MD: 6.7 mm, illustrated in Andrussow (1902, pl. 1, fig. 8) Figs 4B 1 –B 2, Nr. 3/358, SL: 16.9 mm, MD: 6.9 mm, illustrated in Andrussow (1902, pl. 1, fig. 9), Figs 4C 1 –C 2; all TSNIGR Museum Saint-Petersburg (see also Malchevskaya 1985).

Type locality. Utva River (West Kazakhstan Region, Kazakhstan).

Stratigraphy. Late Pliocene/Pleistocene, Akchagylian.

Revised description. Medium sized, conical shell of about 11 teleoconch whorls; apical angle 25–30°, extraordinarily slender shells around 15° may occur. Protoconch turreted, of 3.5 smooth, convex whorls. Early teleoconch whorls with prominent spiral cord placed at mid-whorl, coinciding with periphery, and slightly weaker spiral cord some distance from abapical suture. Third weak spiral cord appears on subsutural ramp on fourth to fifth teleoconch whorl, but may be absent throughout ontogeny. Spiral cords crossed by opisthocline axial ribs, separated by slightly wider interspaces, bearing weak beads at intersections with spiral sculpture. Later teleoconch whorls convex with weakly convex subsutural ramp. Forth weak spiral cord may appear at abapical suture, usually largely covered by subsequent whorl. Strength of spiral cords highly variable, ranging from almost smooth to prominent; secondary spiral threads may rarely be intercalated. Beads may be subobsolete to prominent, fading out at various stages of growth. Last whorl strongly convex, rapidly contracting. Base weakly convex with narrow twisted fasciole. Columella moderately excavated. Inner lip forming moderately broad rim, well demarcated from base, adapically adherent to base. Anal canal indistinct. Outer lip convex, not thickened, deeply opisthocyrt in lateral view. Siphonal canal shallow, moderately wide, short, slightly defected to the left.

Synonyms. Like some modern potamidids ( Pirenella conica ), this species is extraordinarily variable, which is reflected by a huge number of names. The understanding of this species, however, was limited by the selection of specimens by Andrussow (1902), who illustrated shells with weak or reduced sculpture. Therefore, authors such as Kolesnikov (1950), K.A. Ali-Zade (1940) and A.A. Ali-Zade (1967, 1969) distinguished specimens with prominent sculpture as separate species.Already Andrussow (1902) proposed five varieties, separated from the type only by minor differences. Of these, Potamides caspius pyrguloides has weak spiral sculpture without beads, P. c. rotundispira has prominent spiral cords and more convex whorls, P. c. sulacensis has reduced axial sculpture but a slightly more prominent adapical spiral cord, and P. c. zonophora has weak sculpture and a faint secondary spiral cord intercalated between the adapical primary spiral cords. Potamides c. transversa represents a morphotype with slightly more prominent axial sculpture on early spire whorls. All these morphs co-occur and there is no reason to separate any of these as separate species or subspecies (which was not the intention of Andrussow 1902). Later, Kolesnikov (1950) established Potamides eldaricus and P. sumbarensis for slender specimens with subcylindrical whorls or weakly convex profile and prominent beads. Compared to typical Potamides caspius specimens, these morphs represent a somewhat atavistic development, resulting in shells, which are reminiscent of the Middle to Late Miocene Potamides disjunctus . Finally, K.A. Ali-Zade (1940) and A.A. Ali-Zade (1967, 1969) were overwhelmed by the morphological disparity of this species and introduced an absurd number of potamidid species, often based on few specimens and spire fragments. Even the fact that most of these ‘species’ are found co-occurring in the same layers, did not discourage these authors from splitting. Slender shells with prominent beads, close to the eldaricus and sumbarensis -morphs of Kolesnikov (1950), were described as Cerithium aktschagylicum Ali-Zade, 1967 ( Fig. 5A), C. bellum A.A. Ali-Zade & Petrova in Ali-Zade 1969 ( Figs 5D 1 –D 2), C. carum Ali-Zade & Petrova in Ali-Zade, 1969 ( Fig 4F), Potamides comroicus K.A. Ali-Zade, 1940 ( Figs 5C 1 –C 2), P. taribanicus K.A. Ali-Zade, 1940 ( Figs 5B 1 –B 2), and P. tuberculata Ali-Zade, 1940 . For specimens with dominant axial sculpture Ali-Zade (1967) and A.A. Ali-Zade & Kabakova in A.A. Ali-Zade, 1969 established Cerithium ebersini ( Figs 4D 1 –D 2), C. kambai ( Fig. 4J), C. naphtalanicum and C. tichomirovi . Cerithium danatense A.A. Ali-Zade, 1967 ( Figs 4E 1 –E 2) was used as name for a stout morph with prominent beads and spire fragments or subadult specimens were described as C. modicum A.A. Ali-Zade & Kabakova in Ali-Zade, 1969 ( Figs 4H–I). For nearly smooth or completely smooth, often slender elongate morphs, these authors introduced Potamides deformatus K.A. Ali-Zade, 1940 ( Figs 5F 1 –F 2), Cerithium jumudicum A.A. Ali-Zade, 1967 ( Fig. 5G), P. kolesnikowi K.A. Ali-Zade, 1940 ( Figs 5E 1 –E 2), C. kovalevskii A.A. Ali-Zade, 1967 , C. kuraense A.A. Ali-Zade & Kabakova in Ali-Zade, 1969 (strongly reworked) ( Fig. 5H) and C. rectum Ali-Zade & Kabakova in Ali-Zade, 1969. A stout and weakly sculptured variety was described as Cerithium cordatum Ali-Zade & Kabakova in Ali-Zade, 1969 ( Figs 4G 1 –G 2). A highly aberrant specimen was described even as a new genus and new species: Bogatschevia bogatschevi A.A. Ali-Zade & Kabakova in Ali-Zade, 1969 (see discussion on the synonyms of Potamides ) ( Figs 6A–B). Another example for a Pliocene Potamides with huge morphological variability is Potamides granosus ( Borson, 1821) for which Brunetti (2013) traced about 15 synonyms.

Note that only a small part of the specimens described by K.A. Ali-Zade (1940, 1954) and A.A. Ali-Zade (1967, 1969) is still preserved at the Earth Science Museum at Moscow State University ( Russia). These are illustrated herein. All other types, including the holotype of Bogatschevia bogatschevi , seem to be lost. Herein we illustrate a shell representing the Bogatschevia bogatschevi morph from Naftalan ( Azerbaijan), SL: 19.2 mm ( Figs 6B 1 –B 2).

Discussion. Andrussow (1902: 124) discussed a close relationship between Potamides caspius , and the Sarmatian Potamides disjunctus (J. de C. Sowerby, 1832) , and the Maeotian Potamides disjunctoides (Sinzow, 1897) [= Potamides taitboutii (d’Orbigny, 1844) ], but distinguished it from these species based on the weaker sculpture. Indeed, Potamides caspius seems to represent the last member of the Potamides disjunctus — P. taitboutii lineage. The early Maeotian transgression is currently dated at around 7.5 Ma ( Palcu et al. 2019) and the early Akchagylian started around 2.95 Ma ( Lazarev et al. 2021) (in contrast to 3.6 Ma in Naidina & Richards 2020). This results in a gap of nearly 4 my between Potamides taitboutii and P. caspius . Therefore, one could assume that P. caspius more likely derives from a Mediterranean ancestor, which entered the Eastern Paratethys during the Pliocene. This hypothesis is supported by the occurrence of Potamides in the Romanian (Pliocene) of the Dardanelles Basin ( Taner 1997).

The Pliocene Mediterranean Potamides granosus ( Borson, 1821) has subcylindrical whorls, typically with a slightly angulated periphery close to the abapical suture and prominent sculpture, and does not seem to be close to P. caspius .

Distribution. Potamides caspius is restricted to the Akchagylian of the Circum-Caspian region of Russia, Kazakhstan, Azerbaijan, and Turkmenistan.

Akchagylian (Late Pliocene/Pleistocene): Caspian Region: Adzhidere (=Acýdərə, near Naftalan), Mount Bozdað, Eldari Steppe area, Güzdək, Kudbarekdag Mountain Ridge, Mount Molladað, Naftalan, Mount Qaratəpə, Palantekyan Mountain Ridge, Qaladərəsi Mountain Ridge, Qazanbulaq, Yekəxana ( Azerbaijan), Shiraki Steppe area, Taribani Steppe area ( Georgia) (K.A. Ali-Zade 1936, 1954, A.A. Ali-Zade 1969); Belaya Rostosh' (near Inder Lake, Atyrau Region), Utva River (West Kazakhstan Region, Kazakhstan); Kamyshchai River, Kizilyurt (Daghestan, Russia) ( Goloubiatnikow 1902; Davidaschvili 1932; Kolesnikov 1950); Adzhidere, well Aidin, Chandyr River, Danata, Kopet Dag, Krasnovodsk Peninsula, Kuk-Dzhul, Small Balkhan, Sumbar River ( Turkmenistan) (K.A. Ali-Zade 1936; Kolesnikov 1950; A.A. Ali-Zade 1967).