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Dead specimens of an initially undetermined Parviturbo species were sampled during the EGA95 Cruise, from the Marettimo Valley, Western Sicily. Once reconsidered, the specimens were assigned to the recently described P. sertum Tabanelli et al., 2019, providing first data on the related marine environment. The contextual review of literature data, revealing mistakes and misidentifications that affected both recent and fossil reports, proved that in the Mediterranean four Parviturbo species occurs: P. sertum, P. fenestratus, P. laevisculptus and P. ergasticus, plus at least one undescribed species. Such species, nevertheless, might all be extinct, and their shells attributable to outer shelf in situ Pliocene assemblages and, in minor part, to bathyal reworked deposits.
Key words: Skeneidae, Parviturbo, Mediterranean, biogeography, recent, Pliocene.
The name of a well-known Miocene land snail species, Helix incrassata Klein, 1853 (May) (currently Pseudochloritis incrassata) is not a junior primary homonym of the name Helix incrassata Reeve, 1853 (February), because the latter is unavailable as it is a subsequent erroneous spelling of the name Helix incrustata Poey, 1852 (currently Thysanophora incrustata). Reeve gave Poey as author of incrassata; possibly as a lapsus for the similar word incrustata.
Key words: Nomenclature, subsequent erroneous spelling, Pseudochloritis incrassata, Thysanophora incrustata.
Review of Callistochiton righii from Brazil
do Nascimento, N. G., Maia, R. C., Almeida, S. M. & Jardim, J. A.
Callistochiton righii is reviewed based on preserved specimens collected in northeastern Brazil. A complementary description based on detailed anatomical data is presented and comparisons with other local species are provided. Its distribution is extended about 2,200km northward and about 1,000km southward compared to the previously known range.
Key words: Callistoplacidae, morphology, distribution, Brazil.
The impact of a drought on key freshwater pearl mussel Margaritifera margaritifera populations in Scotland
Cosgrove, P., Shields, D., Anderson, D., Massey, K., Cosgrove, C. & Sime, I.
A prolonged period of high temperatures and low rainfall, created extremely low river levels across much of Scotland during summer 2018. At the time, there was anecdotal evidence that this drought caused significant ecological harm in several locations, including watercourses supporting internationally important pearl mussel populations. Given that the species is highly protected and also critically endangered in Europe, a study was undertaken to quantify the impact of the prolonged dry weather on four priority rivers. The evidence from this study, although mixed, demonstrates that significant drought mortalities can and do occur in Scotland, and by extension could happen elsewhere in the species’ northern range. Previous studies on the impact of drought have taken place in populations at the southern edge of the species’ range, and we recommend restorative actions that should help pearl mussel populations better adapt to the likelihood of increased drought events in the future.
Key words: Freshwater pearl mussel, drought, climate change, Margaritifera margaritifera.
Rocellaria dubia is under-recorded in the British Isles due to its habit of boring into hard substrata leaving only its siphons showing. The calcareous siphonal tubes which cover the siphons persist for a considerable time and can be used to identify R. dubia with a high degree of certainty. This paper provides descriptions and images of its siphonal tubes intended to assist with the correct indentification of further records of this cryptic species. In the British Isles R. dubia siphonal tubes are colonised by a wide range of epibionts and the use of SACFOR abundance recording (for an animal of 1–3cm) based on the siphonal tubes is tenable.
In the British Isles R. dubia appears restricted to calcareous substrata including carbonate-cemented sand- and mud-stones and is an important eroder of these. It is highly tolerant of sediment veneers. Open bivalve bores under fine sediment veneers offer microhabitats to small sediment infauna by harbouring pockets of deeper sediment less subject to periodic ‘clearance’ than the surrounding sediment. The importance of biogenic erosion by R. dubia and other borers on subtidal rock exposures may be significantly under-estimated at the time of writing.
Key words: Gastrochaenidae, siphonal tube, substratum, crypt, biogenic erosion.
The present paper reports the presence of living populations of Morlina glabra (Rössmässler, 1835) in the Benelux and gives a first glance at the extent of the range in the three countries. This species, originating mainly from southern European mountains, has been present since at least 2014 in Belgium and 2018 in the Netherlands but was previously misidentified, mainly by confusion with Oxychilus navarricus helveticus. It was presumably introduced accidentally by man and seems to have largely spread on its own in both artificial and natural habitats. We recommend a rapid assessment of the environmental risks of this non-native species with a high invasive potential.
Key words: Oxychilus glaber, first record, non-native. species, Oxychilus navarricus helveticus, citizen science, distribution.
First record of Baeolidia moebii Bergh, 1888 (Nudibranchia: Aeolidiidae) from India based on integrative taxonomy
Dixit, S., Vishnu, K. V., Ameri, S., Manjebrayakath, H. & Saravanane, N.
Baeolidia is the most diverse genus under the family Aeolidiidae. The genus has a widespread distribution with records from the Indo-Pacific, central and eastern Pacific, Red Sea, and Mediterranean Sea. Until now, this genus was represented by only one species from India, Baeolidia salaamica, however, we report Baeolidia moebii as a new record to India and the second species from the subcontinent. This paper not only provides the first sequences of mitochondrial (COI and 16S) DNA for the species from the Indian Ocean but also discusses the possibilities supporting its Lessepsian migration and the relationship between B. moebii and B. australis.
Key words: Heterobranchia, Northern Indian Ocean, Agatti Island, Lakshadweep, new record, Lessepsian migration.
New species of Caliphylla (Gastropoda: Hermaeidae) from tropical southwestern Atlantic
Alves, J., Lima, M., Johnsson, R. & Neves, E. G.
Caliphylla mediterranea A. Costa, 1867, described from the warm and temperate Mediterranean Sea, is the type species of a cosmopolitan genus hitherto considered monospecific. Several notable variations are noted in the records around the world, but gaps in the knowledge of the sea slug anatomy have negatively reflected on the Caliphylla taxonomy. Thus, in line with modern integrative taxonomical studies, the morphology and anatomy of the Caliphylla from Northeastern Brazil (11°–13°S) were investigated. As a result, we describe a new species to the Tropical Southwestern Atlantic, being the second species of the genus reported worldwide.
Key words: Bahia State, Sacoglossa, Taxonomy, Anatomy, Brazil.
Examination of the syntypes of Lottia peitaihoensis (Grabau & S. G. King, 1928) showed that this species in shell morphology matches well with Lottia goshimai Nakayama, Sasaki & Nakano, 2017. Phylogenetic analysis of the COI gene based on newly obtained specimens of Lottia peitaihoensis and the sequence data of Lottia goshimai deposited in GenBank provided additional evidence for the conspecificity of these two species. The COI pairwise distance between L. peitaihoensis and L. goshimai ranges from 0–0.5%, a divergence much lower than the known interspecific variation of Lottia spp. (8.6–44.5%). In the present study, we formally synonymise L. goshimai with L. peitaihoensis. A lectotype for L. peitaihoensis is designated from syntypes.
Key words: Lottia, lectotype, conspecific, junior synonym, Bohai Sea, phylogenetic inference.
Obituary of Frederick Richard Woodward (1939–2020)
Dance, S. P., Hancock, E. G. & Sutcliffe, R.