Pleurotomella perpauxilla Watson 1881

• Main Authors: Figueira, Raquel Medeiros Andrade, Absalão, Ricardo Silva
• Format: Text
• Language: unknown
• Published: Zenodo 2012
• Subjects: Biodiversity; Taxonomy; Animalia; Mollusca; Gastropoda; Neogastropoda; Raphitomidae; Pleurotomella; Pleurotomella perpauxilla; Ricardo; Northwest Atlantic
• Online Access: https://dx.doi.org/10.5281/zenodo.5632988; https://zenodo.org/record/5632988

Pleurotomella perpauxilla (Watson, 1881) (Figs. 44–46) Pleurotoma ( Defrancia ) perpauxilla Watson, 1881: 468. Clathurella perpauxilla (Watson, 1881): Watson (1886: 359, pl. XXII, fig. 7). Type material : Syntypes BMHN 1887.2. 9.1109 Type locality : West Indies, North of Culebra Island (18 º 38 ’ 30 ”N, 65 º 05’ 30 ”W), 713 m. Material examined : Type material and 18966 [2] OP I # 47; 18967 [1] OP I # 53; 18968 [1] OP I # 58; 18969 [1] OP I # 63; 18970 [1] OP I # 75; 18971 [1] OP I # 83; 18972 [4] OP I # 44; 18973 [2] OP II # 47; 18974 [1] OP II # 49; 18975 [1] OP II # 53; 18976 [4] OP II # 59; 18977 [1] OP II # 61; 18978 [1] OP II # 63; 18979 [1] OP II # 78; 15428 [3] OP I # 49; 17269 [2] OP II # 74. Description : Shell conical, white, up to 5.34 mm long. Protoconch with about 3.5 whorls. Protoconch 1 with rows of tiny crosses. Protoconch 2 with diagonal cancellation on the lower 2 / 3 of the whorls and axial riblets on the upper third. Clear-cut proto-teleoconch boundary. Teleoconch with a subsutural slightly concave area sculptured with several axial riblets and a spiral thread. Below this area, about 10 large oblique axial ribs (on the third whorl) crossed by two spiral cords. Shell surface granulose. Suture very shallow. Base elongated, ornamented with about 12 spiral cords. Inner lip reflected over parietal wall. Outer lip thin. Anterior siphonal canal relatively short and narrow. Aperture elliptical. Geographic distribution : Northwest Atlantic: West Indies (Watson, 1881; Watson, 1886). Southwest Atlantic: Campos Basin, Rio de Janeiro (this paper). Bathymetry : 713 m (Watson, 1881)– 1950 m (this paper). Discussion : Our material is almost identical to the type material of P . perpauxilla Watson, 1881 (fig. 46). Dall (1889: 116) synonymized this species with Mangilia ? elusiva Dall, 1881 (figured in Dall, 1889, pl. XII, fig. 7). Though we have not examined the type material of M . elusiva , the original illustration exhibits clear differences from P . perpauxilla (fig. 43). Dall’s specimen has a larger profile, more angled shoulder and a shorter body whorl. So, until the type material of M . elusiva is directly examined we cannot agree with this synonymy. Pleurotomella perpauxilla is reported for the first time in South Atlantic waters (21–22 ºS). It was previously known to occur in the Caribbean (18 ºN). Its bathymetric range is also increased. The only depth previously reported for this species was 713 m (Watson, 1881) and it has now been found at depths from 722 to 1950 m. : Published as part of Figueira, Raquel Medeiros Andrade & Absalão, Ricardo Silva, 2012, Deep-water Raphitomidae (Mollusca, Gastropoda, Conoidea) from the Campos Basin, southeast Brazil, pp. 1-27 in Zootaxa 3527 on page 23, DOI: 10.5281/zenodo.210977 : {"references": ["Watson, R. B. (1881) Mollusca of H. M. S. Challenger Expedition. Parts VIII-X. Journal of the Linnean Society (London), 15, 388 - 475.", "Watson, R. B. (1886) Report on the Scaphopoda and Gasteropoda collected by H. M. S. Challenger during the years 1873 - 1876. Report on the scientific results of the voyage of H. M. S. Challenger during the years of 1873 - 1876, 15 (42), 1 - 680, 53 pls.", "Dall, W. H. (1889) Reports on the results of dredgings, under the supervision of Alexander Agassiz, in the Gulf of Mexico (1877 - 78) and in the Caribbean Sea (1879 - 80), by the U. S. Coast Survey Steamer ' Blake'. Bulletin of the Museum of Comparative Zoology, 18, 1 - 492, pls. 10 - 40.", "Dall, W. H. (1881) Reports on the results of dredging, under the supervision of Alexander Agassiz, in the Gulf of Mexico, and in the Caribbean Sea, 1877 - 79, by the United States Coast Survey Steamer ' Blake'. Bulletin of the Museum of Comparative Zoology, 9, 33 - 144."]}