Topic
Melanopsidae
About: Melanopsidae is a research topic. Over the lifetime, 9 publications have been published within this topic receiving 177 citations.
Papers
TL;DR: Examination of available genus‐group names for Oriental semisulcospirids supports placement of ‘Melania’jacqueti in the genus Hua, consistent with restriction of the concept of Pleuroceridae s.s.l. to eastern North American species.
Abstract: Morphological and molecular studies have been inconclusive in assessing monophyly of the Pleuroceridae s.l and the affinity of western North American Juga to Asian members of the family currently grouped in the Semisulcospirinae. In part, this has been hampered by the rarity of anatomical accounts for Asian pleurocerids (s.l.). The present study provides a comprehensive anatomical description of ‘Melania’jacqueti— a Vietnamese species of uncertain generic placement forgotten in the scientific literature for over 100 years. This investigation confirmed that ‘Melania’jacqueti and Juga possess a number of features that differentiate them from eastern North American species, including features of the kidney, prostate and pallial oviduct. However, comparative data remain inadequate to allow phylogenetic analysis based on morphological data alone. Consequently, a data set of partial mitochondrial 16S ribosomal RNA gene sequences for 51 pleurocerids (s.l.) and five outgroups (Melanopsidae, Thiaridae), was assembled. Parsimony, Bayesian and Maximum Likelihood analyses are largely congruent and support monophyly of the Pleuroceridae s.l., and of two large clades: (i) a clade of eastern North American species, and (ii) an Asian–American clade with ‘Melania’jacqueti as the critical basal offshoot, decisively anchoring Juga within the Semisulcospirinae as sister to all remaining Asian forms. Given the morphological disparity between these two clades, this result is consistent with restriction of the concept of Pleuroceridae s.s. to eastern North American species, and elevation of the Asian–American clade to the rank of family — the Semisulcospiridae. Examination of available genus-group names for Oriental semisulcospirids supports placement of ‘Melania’jacqueti in the genus Hua. Molecular calibration of the basal split between Semisulcospiridae and Pleuroceridae suggests they diverged in the Cretaceous (approximately 90 million years ago). The origin and diversification of these clades are roughly coincident with the subdivision of Laurasia by epicontinental seas and the opening of the Atlantic basin, consistent with a primarily vicariant explanation for their modern biogeographical distributions modified by dispersal in Juga.
46 citations
TL;DR: In the geologically young Italian Peninsula fossil freshwater melanopsids are known only from Lower Pleistocene sites located around the area occupied by living populations, and their similarity to extant specimens supports the hypothesis that they represent the same lineage.
Abstract: . Vicariance on a microplate dispersed by the formation of the Western Mediterranean is the probable origin of Melanopsis etrusca Villa in Brot, the only melanopsid (Gastopoda: Melanopsidae) living in the Italian Peninsula. It is distantly related to extant melanopsids in Iberia and Morocco, and is restricted to thermal springs in the Maremma of southern Tuscany. This area was an island throughout the Miocene, inferred to have become detached geographically from the Corso—Sardinian block. Alternative explanations conflict with geological, paleontological, ecological and systematic evidence. In the geologically young Italian Peninsula fossil freshwater melanopsids are known only from Lower Pleistocene sites located around the area occupied by living populations. Their similarity to extant specimens supports the hypothesis that they represent the same lineage, having expanded its range during a brief, favourable period. Introduction of M. etrusca by humans, birds or wind is most improbable given its distinctness, similarity to local fossils, and inability for passive dispersal. Long-distance dispersal along brackish lagoons during the late Messinian conflicts with the inferred inability of melanopsids living there to colonize freshwater habitats. Indeed, there are ecological, phylogenetic and geological reasons against invoking the Messinian salinity crisis in order to explain the distribution of most taxa. Other freshwater taxa show distribution patterns similar to that of living and fossil melanopsids. However, congruent area cladograms or generalized tracks may not constitute reliable evaluators of biogeographical hypotheses. The detection of vicariance, as that of any other cause, requires robust reconstructions of the past. By pointing at areas of endemism that deserve urgent action, biogeography can provide a contribution to conservation.
25 citations
TL;DR: In this article, the authors investigated the distribution of melanopsid representatives from the late Cretaceous to the present-day, using a comprehensive and stratigraphically well-constrained fossil record, modern paleogeographical reconstructions and contemporary climate data.
24 citations
TL;DR: The authors' phylogenetic analyses indicate that Melanopsidae are only monophyletic when excluding Holandriana from the Balkans, which was found to be more closely related to Pleuroceridae and Semisuclospiridae than to the remaining melanopsids.
17 citations
TL;DR: In this article, the continental aquatic and terrestrial gastropods found in samples of 11 new boreholes in the Molasse Basin, southern Germany, are reported, belonging to the families Neritidae, Melanopsidae, Pachychilidae, Bithyniidae, Hydrobiidae, Truncatellidae, Viviparidae, Valvatidae(?), Lymnaeidae, Planorbidae, Carychiidae, Zonitidae and Discidae(?).
Abstract: Here, we present the continental aquatic and terrestrial gastropods found in samples of 11 new boreholes in the Molasse Basin, southern Germany. The samples come from the Lower Freshwater Molasse (USM), the Upper Brackish Molasse (OBM; Grimmelfingen and Kirchberg Formations) and the Upper Freshwater Molasse (OSM). The studied segments of these lithostratigraphical units represent the beginning of the lower Miocene (USM), and the uppermost lower Miocene (OBM, OSM). Twenty-four species of terrestrial and freshwater gastropods are reported here, belonging to the families Neritidae, Melanopsidae, Pachychilidae, Bithyniidae, Hydrobiidae, Truncatellidae(?), Viviparidae, Valvatidae(?), Lymnaeidae, Planorbidae, Carychiidae, Zonitidae, Helicidae, Hygromiidae and Discidae(?). We provide remarks on the taxonomy of some of the studied species, including a revision of Theodoxus cyrtocelis, T. obstusangula and T. sparsus (the latter can be considered a synonym of T. cyrtocelis). Finally, we present a paleoecological interpretation for the USM, OBM and OSM based on the gastropod fauna.
11 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2019 | 1 |
| 2016 | 2 |
| 2015 | 1 |
| 2014 | 1 |
| 2009 | 1 |
| 2000 | 1 |