﻿An update to the 2014 nomenclator of Valvatidae

﻿Abstract This contribution is an update to the 2014 compilation of all supra- and (infra-) specific taxa of extant and fossil Valvatidae, a group of freshwater operculate snails near the base of Heterobranchia with a nearly worldwide distribution. This update includes corrections and many additions (two replacement taxon names, 21 mainly fossil taxa previously overlooked, and 37 invalid names) to the 2014 contribution and adds all newly described species (11) during the past eight years. The extensive reference list is directly linked, where possible, to the available electronic source of the cited papers.


Introduction
My compilation of all taxa of extant and fossil valvatid gastropods (Haszprunar 2014) has been positively received by the scientific community and was followed by similar taxonomic work on other important groups of freshwater gastropods such as Neubauer (2016) for Melanopsidae or Neiber and Glaubrecht (2019) for Paludomidae. My work inspired and facilitated several recent papers on the taxonomy of Valvatidae. In particular, Russian authors cleared up the status of many uncertain taxa and provided valuable data and high-quality images of type material (e.g., Sitnikova et al. 2015Sitnikova et al. , 2017Vinarski 2016;Sitnikova 2018;Shirokaya et al. 2019;Andreeva et al. 2021;Osipova et al. 2021).
In contrast, the paleontological analysis of Valvatidae (and other taxa with similar shell morphologies) is still hampered by the unavailability of key literature. Many important and also quite recent taxonomic papers on fossil taxa have been written in non-Roman alphabets and often are not available as a digitized version. Thanks to the kindness of several colleagues, I could access some of the most important papers in particular by Russian or Chinese authorities, and the results of checking the original descriptions and their circumstances are compiled and reviewed herein.
Whereas there is constant progress in detecting and describing new valvatid species, concerning both fossil and extant taxa (Table 1), our understanding of species delimitation in Valvatidae generally is still limited. Also, a robust phylogeny of the family is still in its infancy, since only a few papers have provided molecular data on valvatids (e.g., Hauswald et al. 2008;Clewing et al. 2014;Saito et al. 2018;Falniowski et al. 2021). In particular, the seemingly well-known and widely distributed Valvata piscinalis (O.F. Müller, 1774) is likely to represent a species complex spread all over the Palaearctic and (by introduction) also the Nearctic region.
As a result, there have not been any recent proposals of new genera or further revisions to the supraspecific classification. Accordingly, this update is limited to the species level. The present update adds two extant and nine fossil species recently described, two replacement taxon names, another 21 mainly fossil taxa previously overlooked, and nearly 40 names based on confusions, misspellings, or invalid publications (Table 1). In addition, numerous data on type localities or type material or sequence information are provided. Table 1. List of new names (alphabetically arranged) since publishing of the nomenclator (Haszprunar 2014). † Valvata alta K.A. Ali-Zade, 1932 (NEW) Original source: K.A. Ali-Zade 1932: 21, pl. 2: figs 12-14 (not seen, but according to Ali-Zade 1936: 17).
Type material: Holotype deposited in the Zoological Institute, of the Russian Academy of Sciences, St. Petersburg (No. ZIN 1/533-1968).
Remarks: Unfortunately this fossil species was omitted from the recent review of taxa created by Starobogatov (Sitnikova et al. 2017). Moskvicheva, 1985(in Starobogatov & Zatravkin, 1985 Type material: Holotype deposited in the Zoological Institute of the Russian Academy of Sciences, St. Petersburg (No. ZIN 1/405-1973).
Remarks: As outlined, the name is a junior homonym of Valvata bicarinata Lea 1841. Accordingly, the species has been renamed as Valvata heidemariae willmanni Neubauer, Harzhauser, Kroh, Georgopoulou & Mandic, 2014. Preston, 1916 (Nom: 25) Remarks: Saito et al. (2018) provided molecular data from specimens from the type locality, Lake Biwa, Japan. Westerlund, 1897 (Nom: 26) Type material: Walther and Glöer (2019: 4) checked the taxonomy of the species and although they did not have contact to type material, they concluded that "The original description of V. brandti is based on two lots. One was collected by A. Brandt in Lake Sevan, while the other was found by L. Młokosiewicz near Lagodekhi in Georgia. Between both localities is a distance of more than 150 km. The Lagodekhi record belongs to Caspicyclotus sieversi .... (Cyclophoridae)…..The other lot, however, seems to belong to Valvata piscinalis, which is known to occur in Lake Sevan (e.g., Mashkova et al. 2018)". Dr Pavel Kaijashko (pers. comm. 22 Feb 2022 provided the following additional valuable information: "Indeed, the original description of V. brandti is based on two lots … [mentioned by Walther and Glöer (2019)]. In 1912 W. Lindholm [Lindholm 1912] redefined the Lagodekhi finds and placed them to Cyclotus sieversi (now Caspicyclotus sieversi). The other lot he attributed to the genus Valvata. There is a handwritten entry by W. Lindholm in the ZIN RAS catalogue about this. The specimens of V. brandti collected by A. Brandt are poorly preserved. Nevertheless, their conchological features (shell size, shape and sculpture of the whorls, diameter of the umbilicus) indicate belonging to Valvata (Tropidina), but not to V. piscinalis." Valvata (Cincinna) aliena var. brevicula Kozhov, 1936 (Nom: 26) Type material: Sitnikova et al. (2004) designated a lectotype, which was later illustrated by Sitnikova et al. (2015: fig. 1D). However, Vinarski and Kantor (2016: 274) reported that only syntypes but no lectotype could be found at the Zoological Institute, Academy of Sciences, St. Petersburg (ZIN). Thus, it remains unclear whether or not the designated lectotype has been lost.
Remarks: This subspecies name was mentioned in an unpublished PhD thesis (no ISBN or ISSN numbering) and thus is not formally described as required by ICZN Art. 8.1.3 and 8.6. † "Valvata (Cincinna)" circinata (Greppin, 1855)  If the identity of that other person is not explicit in the work itself, then the author is deemed to be the person who publishes the work", making Greppin the author of Paludina circinata. However, contrary to the classification by Wenz (1928Wenz ( : 2427 this taxon with an extended large whorl and a broad apertural lip is certainly not a valvatid, but much more likely a Lithoglyphus. It is also not identical to those specimens from a nearby locality, which are illustrated and described by Sandberger (1870-1875: 324, pl. 18: fig. 5a-c) as Valvata circinata (and also referred to Merian). Accordingly, both Paludina circinata Greppin, 1855 and Valvata circinata Sandberger, 1871 remain valid taxa. † "Valvata piscinalis var. cistopolitana G.I. Popov" (NEW) cited as "cistopolitana nov.", a nomen nudum in Goretsky (1964: 55) and secondarily by Balabanov et al. (2010: 196).
Remarks: I could not find any trace of this name in the papers of G.I. Popov or in subsequent papers, accordingly a "taxon inquirendum", probably a nomen nudum, not available.

Nerita contorta
Type locality: Xinmin, northeast China. Type horizon: The lower part of the first section of the Eocene-Oligocene Shahejie Formation. Type locality: The locality of the lectotype is unfortunately not provided by Vinarski and Kantor (2016: 268).

Cincinna falsifluviatilis
Type material: Lectotype in the Zoological Institute of the Russian Academy of Sciences, St. Petersburg (ZIN), #1 in the systematic catalogue under the name.

Valvata japonica
Remarks: Saito et al. (2018) provided molecular data of specimens from Doba River (Amori Prefecture) and Sagami-gawa River (Nagano Prefecture), Japan. These data suggest that this species name actually encompasses several biological species. Type horizon: Uppermost Cretaceous, Jiaozhou Formation; sample taken at a depth of 370.5 m.
Type horizon: Upper Lower Pleistocene, grey-yellow silty clays of the Synania Formation.
"Valvata skniadica" mentioned in Ye et al. (1996: 166) Lindholm, 1909 as a junior synonym, provided photographs of syntypes and from specimens of several localities as well as an extensive and annotated citation record in the Russian literature in particular. Andreeva et al. (2021: fig. 3C) added excellent photographs from specimens of the Taz River basin (western Siberia). Draparnaud, 1897 (Nom: 98) Type material: According to Vinarski and Kantor (2016: 263) a single shell (syntype) is stored in the Naturhistorisches Museum Wien (NHM #14717). † Valvata (Cincinna) splendida Szőts, 1953 (NEW) Original source: Szőts, 1953: 33, 145-146, pl Remarks: The name is a mistake based on the description of Valvata subnaticina Łomnicki, 1886 (Nom: 100). There it is stated that fossils of forms similar to Valvata radiatula Sandberger, 1875 also occur at the type locality; the latter are clearly different from V. subnaticina, however.

Acknowledgements
I would like to thank many colleagues who provided me with previously nondigitized literature, in particular Gert Wörheide (GeoBio-Center, Ludwig-Maximilians-University of Munich), who made the book of Youluo (1978) available, and Thomas A. Neubauer (Justus-Liebig-University of Gießen), who provided copies of the papers of the Ali-Zade family and several other important taxonomic works of the former Soviet area. Also, Dr Neubauer's substantial work to update MolluscaBase and his comments as editor of ZooKeys were a significant help during the preparation of this work. I am indebted to the reviewers of the typescript, Mathias Harzhauser (Natural History Museum of Vienna), Alan Kabat (Harvard Museum of Comparative Zoology), and Pavel Kijaskho (Russian Academy of Sciences, St. Petersburg), who all provided significant help and data in order to improve the paper.