Anatomy, functional morphology, evolutionary ecology and systematics of the invasive gastropod Cipangopaludina japonica (Viviparidae: Bellamyinae)

Abstract

The anatomy, functional morphology and evolutionary ecology of the Viviparidae, and the subfamily Bellamyinae in particular, are incompletely known. Partly as a result, genealogical relationships within the family remain poorly understood. Because of this lack in knowledge, few informed hypotheses exist on ancestral states, how differences in body plans between the subfamilies evolved, and how the peculiar biogeographic distribution patterns of viviparids have arisen. Here we document the anatomy, morphology, life history and systematics of Cipangopaludina japonica, a Japanese species that has been introduced into North America, to resolve taxonomic confusion and to improve our understanding of how form and function are related in bellamyines. Anatomical and histological examinations demonstrate marked differences between C. japonica and other bellamyines in the radula, salivary gland, kidney, nerve ring and reproductive organs. Substantial differences also exist between male and female body organization, but conchological differences between sexes in semi-landmark morphometric analyses are limited. The volume of the brood pouch of females, and hence body and shell size, appear to be good predictors of reproductive success, and the species' ecological versatility may relate to high fecundity and the ability to alternate between feeding modes. Comparing our observations on C. japonica with other viviparids and basal Architaenioglossa, we identify several persistent misinterpretations in the literature on how form and function are related in viviparids, not in the least as to female reproductive anatomy. Our reinterpretations improve understanding of the evolution of Viviparidae and its subfamilies, and hopefully will allow future workers to isolate key traits that shaped the evolution of viviparids at the taxonomic levels of their interest for more detailed studies.

Studies on the Functional Morphology of the Digestive System of the Fresh Water Thiarid Snail, Mieniplotia scabra (MÜLLER, 1774), Family Thiaridae New to Egypt

“…The basic anatomical structure of the digestive system of the Egyptian thiarid snail Mieniplotia scabra conforms to that of any other style bearing snails (Graham, 1939;Moustafa (1987); Strong & Glaubrecht , (2003); Vogler et al , (2014); Bocxlaer and Strong (2016); Khalil & Aly (1997). It consists mainly of the mouth, which leads to the pgayngeal cavity (StarmÜhlner, 1969), the muscular buccal mass, the esophagus, the stomach, the style sac, the intestine, the rectum which ends with the anal papilla and the glandular structures which are the digestive and salivary glands.…”

Role of ancient lakes in genetic and phenotypic diversification of freshwater snails

“…): as juveniles(Van Bocxlaer & Strong, 2016) 20-43/4.5-6.5 mm: as embryos (this study) Ussuripaludina 5-70/4.5-8.0 mm: as embryos (this study)A3Margarya 6-8/5 whorls: as embryos (indicated as C. dianchiensis in Lu et al, 2014) 2-8/exceeding 10 mm: as juveniles(Zhang et al, 2015) …”

Diversity and Predicted Function of Gut Microbes from Two Species of Viviparid Snails

“…Campeloma decisum and Ci. japonica occupy similar habitats and ecological niches: individuals are frequently found on soft sediments in rivers and lakes, and both species are presumed to filter feed from the water column as well as ingest organic material present in the substrate (Allison 1942;Chamberlain 1958;Bocxlaer and Strong 2016).…”