Gundlachia dutrae: n. sp. from northwest Brazil (Mollusca: Basommatophora: Ancylidae)

Abstract

A new species of Gundlachia, Gundlachia dutrae is described from northwest Brazil. It is distinguishable from other congenerie species by characteristics of the shell, radula and internal organs. Shell relatively high. Aperture near-circular; periostracum dark brown without periostracal hairs. Apex slightly inclined to the right, projected but not hooked, with an apical depression surrounted by a sculpture of well-marked irregular punctations. Shell surface with prominent radial sculpture. No septate specimens were observed. Ratios (n= 59): shell width/shell lenght = 0,66- 0,79 (mean 0,73); shell height/shell length = 0,32- 0,45 ( mean 0,37); shell height/shell width = 0,43- 0,63 (mean 0,51). Body of normal ancylid type; mantle pigmentation dark brown or black, concentrated along the mantle collar. The dorsal surface of the right anterior muscle is elongated and medially constricted. The left anterior and the posterior muscles are almost elliptical. Adhesive area is V-shaped. Pseudobranch unpigmented bearing a very small and thin dorsal lobe. Ovotestis with more than 25 unbranched diverticula. Ovispermiduct with seminal vesicle rather developed. Elongated nidamental gland continous with the glandular wall of the uterus. Nidamental gland appendix ending into a bulbous swelling Spermathecal body almost rounded. Well-developed prostate with five long diverticula. Ejaculatory complex with long glandular flagellum, without a penis or true ultra-penis. "Penis sheath" developed. "Ultra-penis" projected as a tube inside the lumem of prepuce, with a slit between "ultra-penis" and "penis sheath". Rachidian tooth tetracuspid, with two median cusps assymmetrical and aculeated. Lateral teeth tricuspid, with a reduced endocon and a prominent mesocon. A well marked gap occurs between meso and ectocon. Marginal teeth similar to lateral ones. Jaw T-shaped, with about 28 dorsal plates

The genus Anisancylus Pilsbry, 1924 (Planorboidea, Ancylinae) in South America: species distribution and new records

“…ARGENTINA: Córdoba (Rumi et al 2006, Rumi et al 2008, Ovando et al 2014; Cabana (Ovando et al 2014 ; Alegrete ; Toropi River Basin, Toropi (Martello et al 2014). CHILE (ANSP 124236, USNM 573469): Aconcagua: Estero San Isidro, Quillota; Estero San Pedro, Quillota Lanzer 1994, Santos 2000); Capilla Caleu (Ohlweiler and Lanzer 1993, Santos 1994, Santos 2003a (Ohlweiler and Lanzer 1993). Maldonado (Barattini 1951).…”

“…Anisancylus dutrae (Santos, 1994) Gundlachia dutrae Type locality. Estação Ecológica do Tapacurá, São Lourenço da Mata, Pernambuco state, Brazil.…”

“…7). BRAZIL: Pernambuco: São Lourenço da Mata (Santos 1994), Riacho Pascoal, Custódia (Santos 1994); Poço da Cruz, Salgadinho, Recife (Santos 1994); Ibimirim (Santos 1994); Sanharó (Santos 1994); Sirinhaém River, Ribeirão (Col. Mol. UERJ).…”

“…For first time, we recorded A. dutrae (Santos 1994) in Minas Gerais state and 2 new localities in northeastern Brazil. Anisancylus obliquus (Broderip & Sowerby, 1832) is widely distributed in Chile, Peru, central and southern Argentina, Uruguay and southern Brazil while A. dutrae is restricted to Brazil.…”

“…He designated as type species Ancylus obliquus Broderip & Sowerby, 1832 (now Anisancylus obliquus), from Chile. Anisancylus is endemic to the Neotropical region and is composed of 2 nominal species: Anisancylus dutrae (Santos, 1994) and A. obliquus. Both species are common in lotic environments, under stones or on their surfaces, and, rarely, on fallen leaves (Santos 1994, Ovando et al 2014.…”