First record of broad-snouted seven-gilled shark from Cananéia, coast of Brazil
Victor Sadowsky
Instituto Oceanográfico da Universidade de São Paulo
A young female (T.L. 753 mm) of the broads-nouted seven-gilled shark, Notorynchus pectorosus (GARMAN, 1913), was caught on June, 1968, in a gill net at depth of 6 m off Cananéia (25ºS, 47º52'W). The bottom water temperature at the the time of capture was 20.6ºC.
Together with it some other sharks, Rhizoprionodon porosus Poey, Rh. lalandei. Val., and Carcharhinas porosus (Ranzani), were captured, all adult males.
The species Notorynchus pectorosus is distributed in the Pacific and Indian Oceans, as well as in the southern Atlantic, off Argentina (LAHILLE, 1928) and South Africa (SMITH, 1953), while it was not recorded from other parts of the Atlantic (BIGELOW & SCHROEDER, 1948; MANDAY, 1968; TORTONESE, 1956; CADENAT, 1950; and others), and not from Brazil (FOWLER, 1942) nor from the region of Cananéia (SADOWSKY, 1967).
The specific characters of the shark from Cananéia correspond perfectly to those of Garman's description (1913, p. 20-21); however, they show some differences concerning the morphological proportions compared with the description of the same species given by LAHILLE (1928) and CHEN (1963) under the name of Heptranchias pectorosus GARMAN, 1884. These differences might be due to allometric growth, as the examined specimens were of quite different sizes: that from Cananéia was 753 mm long, those of CHEN and of LAHILLE, 1930 mm and 2070 mm, respectively.
As the nomenclature of the genus to which the species belongs is doubtful, I adopt the one recently used by GARRICK & SCHULTZ (1963).
As the scientific literature does not yet contain detailed data referring to the morphology of young specimens of the species, I give the measurements of the present material (Table I) according to the indications of BIGELOW & SCHROEDER (1948) and others (TORTONESE, 1956; SADOWSKY, 1968), and add a short description of the observed peculiarities.
In fresh state the color of the back of N. pectorosus (Fig. 1) was greyish violet, the ventral side greyish white (lead or ice). During preservation in formol 10% the color of the back changed to yellowish pink, while the ventral side retained its color. The dark spots scattered irregularly on the dorsal side are roundish; their diameter varies from 2-18 mm. On the central part of the head, a little in front of the spiracula, there are two small endolymphatic pores, with an interspace of 1.5 mm. The upper edge of the caudal fin is protected by 3 or 4 series of enlarged dermal denticles. The same denticles, only a little less stout, occur also on the edges of the anterior border of all the other fins.
The dental formula is: (9)-6-1-1-1-6-(8) for the upper teeth, and: (7)-6-1-6-(6) for the lower teeth. The numbers in brackets indicate the series of very small teeth which form a plate of about 12 mm in length. In the upper jaw there is a central tooth. The central series and the two para-central ones each have 2 typical funcional teeth, the other series, only one. The lower median tooth has a median notch and 3 cusps on either side.
The specimen is preserved in the collection of the Oceanographic Station at Cananéia.
For the translation of the manuscript I thank Mrs. Eveline Marcus.
REFERENCES
BIGELOW. H. & SCHROEDER, W. 1948. Sharks. In: Fishes of the Western North Atlantic, Mem. Sears FdnohL Res., vol. 1, n.º 1, p. 59-576.
CADENAT, J. 1950. Poissons de mer du Senegal. Dakar, I.F.A.N., 345 p.
CHEN, J. 1963. A review of the sharks of Taiwan, Biol. Bull. Coll. Sci. Tunghai Univ., Ichthyol. ser., n.º 1, p. 1-102.
FOWLER, H. 1942. A list of the fishes known from the coast of Brazil. Archos Zool. Est. S Paulo, vol. 3, p. 115-184.
GARMAN. S, 1913. The Plagiostomia (sharks, skates and rays). Mem. Mus. comp. Zool. Harv., vol. 36, p. 1-515.
GARRICK, J. & SCHULTZ, L. 1963. A guide to the kinds of potentially dangerous sharks. In: Gilbert, P., ed. - Sharks and survival. Boston. D. G. Heath, p. 3-60.
LAHILLE, F. 1928. Nota sobre unos peces elasmobranquios. An. Mus. nac. Hist. nat. "Bernardino Rivadavia", vol. 34, n.º 12, p. 299-339.
MANDAY, D. G. 1968. Guia para los tiburones de aguas cubanas. Inst. oceanogr., Acad. Cienc. Cuba, ser. Oceanol., n.º 1, p. 1-60.
SADOWSKY, V. 1967. Selachier aus dem Litoral von São Paulo. Brasilien, Beitr. neotrop. Fauna, vol. 5, n.º 2, p. 71-88.
SADOWSKY, V. 1968. On the measurement of the total length of sharks. Zool. Anz., vol. 181, n.º 3/4, p. 197-199.
SMITH, J. 1953. The sea fishes of Southern Africa. South Africa, Central News Agency, 564 p.
TORTONESE, E. 1956. Leptocardia ciclostomata selachii. Bologna, Calderini, 334 p. (Fauna d'Italia, vol. 2).
(Received in 8/5/1969)
Publ. n.º 277 do Inst. Ocean. da USP.
- CADENAT, J. 1950. Poissons de mer du Senegal. Dakar, I.F.A.N., 345 p.
- CHEN, J. 1963. A review of the sharks of Taiwan, Biol. Bull. Coll. Sci. Tunghai Univ., Ichthyol. ser., n.ş 1, p. 1-102.
- FOWLER, H. 1942. A list of the fishes known from the coast of Brazil. Archos Zool. Est. S Paulo, vol. 3, p. 115-184.
- GARMAN. S, 1913. The Plagiostomia (sharks, skates and rays). Mem. Mus. comp. Zool. Harv., vol. 36, p. 1-515.
- GARRICK, J. & SCHULTZ, L. 1963. A guide to the kinds of potentially dangerous sharks. In: Gilbert, P., ed. - Sharks and survival. Boston. D. G. Heath, p. 3-60.
- LAHILLE, F. 1928. Nota sobre unos peces elasmobranquios. An. Mus. nac. Hist. nat. "Bernardino Rivadavia", vol. 34, n.ş 12, p. 299-339.
- MANDAY, D. G. 1968. Guia para los tiburones de aguas cubanas. Inst. oceanogr., Acad. Cienc. Cuba, ser. Oceanol., n.ş 1, p. 1-60.
- SADOWSKY, V. 1967. Selachier aus dem Litoral von São Paulo. Brasilien, Beitr. neotrop. Fauna, vol. 5, n.ş 2, p. 71-88.
- SADOWSKY, V. 1968. On the measurement of the total length of sharks. Zool. Anz., vol. 181, n.ş 3/4, p. 197-199.
- SMITH, J. 1953. The sea fishes of Southern Africa. South Africa, Central News Agency, 564 p.
- TORTONESE, E. 1956. Leptocardia ciclostomata selachii. Bologna, Calderini, 334 p. (Fauna d'Italia, vol. 2).
Publication Dates
-
Publication in this collection
13 June 2012 -
Date of issue
1969
