On Pomacea sordida (Swainson, 1823) (Prosobranchia, Ampullariidae)

Abstract

A description of Pomacea sordida (Swainson, 1823) collected in Caxias and Nova Iguaçu, state of Rio de Janeiro, is presented. The shell is globose, heavy, whith greenish or horn-colored periostracum and dark spinal bands; apex subelevated, 4-5 moderately shoudered whorls, increasing rather rapidly and separated by deep suture. Aperture large, moderately round, yellowish or violaceous; lip thick and sometimes dark brown; umbilicus large and deep; operculum corneous and heavy, entirely closing the aperture. Ratios: shell width/shell length = 0.81-0.91 (mean 0.86); aperture length/shell length = 0.66-0.75 (mean 0.70). Testis, spermiduct and penis pouch as in Pomacea lineata (Spix, 1827). Seminal vesicle whitish and bean-shaped. Prostate cylindric and narrow, cream in coloar as the testis. Penis whiplike whith a closed circular spermiduct. Penial sheath elongated and tapered, with its distal tip turned to the right; outer basal gland situated on the left; inner median gland rounded; apical gland elongated and wrinkled. Ovary composed of branched whitish tubules lying superficially on the digestive gland; oviduct and seminal receptacle as in P. lineata; albumen gland yellowish - orange. Vestigial male copulatory apparatus (penis and its sheath) present in all females examined.

Insights from an Integrated View of the Biology of Apple Snails (Caenogastropoda: Ampullariidae)

“…At about the same time, the primordium of the copulatory apparatus appears near the inner right mantle edge and will develop either into the full copulatory apparatus of adult males or the rudimentary apparatus of adult females (Gamarra-Luques et al, 2013). The occurrence of this copulatory rudiment has also been reported in adult females of other Pomacea species (Thiengo, 1987(Thiengo, , 1989Thiengo et al, 1993) and of M. cornuarietis (see Schulte-Oehlmann et al, 1995), but is not attributed to masculinizing pollutants often associated with this phenomenon in other gastropods. Although sometimes apparently lacking , this rudimentary copulatory apparatus in females can continue to grow after sexual maturity, even in the absence of masculinizing pollutants (Gamarra-Luques et al, 2013; see Environmental Health and Pollution).…”

“…The ovary forms a layer of arborescent tubules beneath the mantle epithelium (Thiengo, 1987(Thiengo, , 1989Thiengo et al, 1993). The tubules are lined by the germinal epithelium, composed of Sertoli cells and oogenic cells (i.e., oogonia and previtellogenic and vitellogenic oocytes; Martín, 1986).…”

Molluscan Models in Evolutionary Biology: Apple Snails (Gastropoda: Ampullariidae) as a System for Addressing Fundamental Questions*

“…While the overall family-level morphology of ampullariids is relatively constrained, many species exhibit wide ontogenetic and ecophenotypic conchological variation, making identifi cation and delimiting of species based on conchology alone very difficult. Internal anatomy offers some resolution (Thiengo 1989, Thiengo et al 1993, but molecular analyses have begun to make it possible to identify welldemarcated lineages (species) , and provide a phylogenetic framework to resolve fundamental taxonomic and systematic problems and address major evolutionary questions. Their long evolutionary history, wide geographic distribution, and high biodiversity make them especially well suited for studying biogeography, biodiversifi cation, and novel adaptations to provide further insights into evolutionary biology in general.…”

Development of a penis from the vestigial penis in the female apple snail, Pomacea canaliculata

“…It is well known that some molluscs exhibit unusual sexual diversity and hermaphroditism (2,3). One of the most interesting features of members of the Ampullariidae is that females in 5 of the 10 genera-namely, Pila (4,5,6,7,8,9,10,11,12), Pomacea (13,14,15,16), Lanistes (13,17,18), Afropomus (19), and Turbinicola (13)-have a socalled vestigial penis in addition to the normal reproductive system (Fig. 1).…”