Anatomia e desenvolvimento intracapsular de Neritina zebra (Bruguiere, 1792) (MOLLUSCA, GASTROPODA, NERITIDAE)

Abstract

Neritina zebra is a common gastropod on mud bottom and brackish water. This study aims to review the literature and add information about the anatomy of Neritina zebra. We analyzed the animals collected in the estuary of the Ceará river – CE, in “Parque Estadual do rio Cocó” - CE and specimens deposited in “Coleção Malacológica Prof. Henry Ramos Matthews" (CMPHRM) of “Universidade Federal do Ceará” (UFC) and “Coleção de Moluscos do Museu de Zoologia da Universidade de São Paulo” (MZUSP). The radula was observed and photographed through optic and scanning electron microscope (SEM). The protoconch was observed and photographed by SEM. N. zebra presents globose shell, protoconch with 1.5 whorls, teleoconch with 3.5 whorls, small teeth on inner lip, low spire, semilunar aperture. Shells present several different colors and patterns of zigzag. The columella forms a transversal septum. Operculum calcareous, smooth, with bifurcated apophysis. The columellar muscle is well developed, with two parts of different sizes. Bipectinate gill. The osphradium is in front of the suspensory membrane of the gill, on the left side of the mantle. The heart presents one auricle and one ventricle. The radula is rhipidoglossa type, presenting the general formula .5.1.5. . Long esophagus and intestine. The intestine passes through the pericardial cavity, enwrapped by the ventricle. The male reproductive system presents one genital opening, very long and coiled spermatic duct, prostate gland and penis with laminar shape on the right side of the cephalic region. The female reproductive system has three genital pores (vaginal pore, main female gonopore and enigmatic duct), a reinforcement sac, a spermatophore sac, an ovary with many small parallel digitiformes vilosities, a seminal receptacle and the albumen and capsule glands.