
BULLETIN OF MARINE SCIENCE, 28(2): 282-296, 1978 VOSSELEDONE CHARRUA: A NEW PATAGONIAN CEPHALOPOD (OCTOPODIDAE) WITH NOTES ON RELATED GENERA Francisco J. Palacio ABSTRACT A new octopodan genus, Vosseledone, and its type species, Vosseledone charrua, is described from the Patagonian Province. The new taxon is characterized by the possession of a degenerate radula and a well developed ink sac. Its position in reference to the closely related genera is reviewed. In the course of a study of the coastal MORG, Museu Oceanografico de Rio Cephalopoda of Brasil, I encountered seven Grande do SuI, Brazil; BMNH, British specimens which represent a new genus of Museum of Natural History; UMML, Uni- incirrate octopods with uniserial suckers versity of Miami, Marine Laboratory. that occurs in the southwest Atlantic Ocean. I have examined three specimens from a col- Family OCTOPODIDAE Orbigny lection kindly loaned by E. C. Rios of the Subfamily ELEDONINAE Gray Museu Oceanografico de Rio Grande, Rio Vosseledone new genus Grande do SuI, Brazil. Four additional Diagnosis.-Octopod with uniserial suckers. specimens had been sent to G. L. Voss, Ink sac large superficially imbedded, evident University of Miami, by Z. de Castellanos externally. Radula degenerate with tall, re- of the Instituto de Biologia Marina, Mar curved, simple rachidian tooth with narrow del Plata, Argentina, originally believed to base; faint traces of first laterals; second represent Tetracheledone spinicirrus from laterals degenerate with proximal cuspless the coast of Uruguay. A preliminary study prominence; third laterals and marginal suggested the possibility that the specimens plates lacking. Third right arm hectocoty- belonged to the genus Thaumeledone Iized with strong, well differentiated ligula; Robson, 1930. The type specimens of calamus deeply grooved. Arm heteromor- Thaumeledone brevis and T. gunteri were phism absent. Digestive system with nor- made available for study by the courtesy of mal esophageal crop. Funnel organ V V J. F. Peake of the British Museum of Nat- type. Large eggs and spermatophores. ural History. Measurements and indices given in this Type species.-Vosseledone charrua n. sp. paper have been defined by Voss (1963) with the exception of Hectocotylized Arm Vosseledone charrlLa new species Index (HeAL) used here as the mantle Figures 1-5; Tables 1-6 length expressed as percentage of the Charruan octopus. Pulpo charrua. Polvo hectocotylized arm length (MHI, of Pick- charrua. Tetracheledone spillicirrus, Caste- ford, 1964); and Fellow Arm Index (FAI), llanos y Menni, 1968: 18; 1969: 73, 77 (non defined here as the hectocotylized arm Tetracheledone spinicirrus Voss, 1955). length expressed as a percentage of the Material examined.-HOLOTYPE, one male. symmetrical fellow arm length (HAl, of mantle length 49 mm. 35°14'S, 52°28'W, east of Punta del Este, Uruguay, in 200 m, USNM Pickford, 1964). Scanning electron micro- 729454. PARATYPES: 2 males, mantle lengths scope photographs were taken by W. 50 and 53 mm, and one gravid female, mantle length 61 mm, collected with the holotype, Charm, RSMAS. Abbreviations used are: UMML 1681. One male, mantle length 50 mm, USNM, United States National Museum of and one gravid female, mantle length 58 mm, 33° 17'S, 52°40'W, off Albardfto, Rio Grande do Natural History, Smithsonian Institution; SuI, in 100 m; collected by ALINE, October 282 PALACIO: A NEW PATAGONIAN CEPHALOPOD 283 l" ,. r r ,. r ,.. r r' ,.. r ........ r " r r ,.. r r r ""1",:- r r r r r d a b Figure 1. Vosse/edolle e1wrrua, new genus and species: a, dorsal view of male; b, funnel organ; c, digestive system; d, upper mandible; e, lower mandible, 284 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.2, 1978 Figure 3. Vosseledolle clwrrua, new genus and species. Radula. erect and strong; they are largest near the Figure 2. Vosseledone charrua, new genus and edge of the web and minute distally. Almost species. Male hectocotylus. half the suckers are found on the distal one fourth of the arm. The web is moderately 1970, USNM 729455. One female, mantle length deep with an average index of 34. Sector C 76.5 mm, from Sao Sebastiao, Sao Paulo, in 10 m, is usually deepest; sector E is usually the collected by J. Ribeiro, 20 December 1945, shallowest. MORG 10701- The third right arm is hectocotylized; it is Description.-Vosseledone charrua is a only slightly shorter than the corresponding small octopod. The mantle is globular and left arm. The hectocotylus is muscular and wide, its length about one third of the total massive with a ligula index of 8.4-11.1. The length. The mantle width is accentuated in ligula is deeply excavated with few gravid females. The head is not as wide as laminae; the lateral margins are strong and the mantle and the neck is not constricted. somewhat rolled inward. The calamus (Fig. The eyes are prominent and occupy a large 2) is large (CLI 43.1-58.8) and strong, portion of the head area. The pallial aper- deeply grooved, and very acute apically. The ture is wide. spermatophoral groove is prominent with a The funnel is stout and muscular, free wide, strongly infolded membrane. for about half of its length. The funnel There are 6-7 gill filaments per outer organ consists of two thick V-shaped pads demibranch. The digestive system of one which are acute apically. The basal funnel male and one female were dissected. The flaps are strong and with the corresponding beaks (Fig. Id-e) offer no special charac- depressions of the mantle constitute a ters. The radula is degenerate (Figs. 3-5), powerful mantle-locking apparatus. possessing a tall recurved and simple The arms are strong, about twice as long rachidian tooth with a narrow base. There as the mantle, with an ALI of 58-67 and are faint traces of first laterals. The second an AWl of about 21. The arms are nearly laterals are degenerate and exhibit a proxi- equal in length and show no particular arm mal prominence without a cusp. The third order. The suckers are uniserial, large, laterals and marginal plates are lacking. PALACIO: A NEW PATAGONIAN CEPHALOPOD 285 Figure 5. Vosseledolle c1wrrua, new genus and species. Lateral view of rachidian tooth. Figure 4. Vosseledolle charrua, new genus and species. Delail of rachidian tooth and atrophied laterals. ulum. Needham's sac contains a few (three in specimen No.2) large spermatophores (Fig. 6a). These are long (SpLI 100-112) The digestive tract is of the normal and slender (SpWI 5-8); the convoluted octopodan type. Anterior and posterior tube of the sperm receptacle occupies 36- salivary glands are present. The esophagus 42% of the tube length; the cylinder and is anteriorly expanded into a crop. The cement body, about 20% and the ejaculatory stomach is smalIer than the spiral caecum. apparatus is almost as long as the receptacle. The surface of the latter has small protrud- The anterior third of the ejaculatory tube is ing nodules which are probably the result arranged as a spiral band, the midportion of undetermined parasitic or bacterial in- resembles flakes disposed along a main axis fections. The caecum is followed by a large and the oral segment is slightly spiraled. intestine which is recurved midway to its The ovary is large with stout proximal junction with the ink sac orifice in the anal oviducts. The ovary (Fig. 6c), of a gravid region. The liver is large and ovoid; the female (specimen No.1), contained about pancreatic region is connected with the 40 differentially developed, closely clustered, spiral caecum by paired hepatopancreatic 10ngitudinalIy striated eggs (Fig. 6d). The ducts. The ink sac is large and fusiform, apparently mature eggs are about 13 mm about half as long as the liver into which it by 4 mm with prominent stalks. is superficially imbedded but externally evi- The sculpture, in preservation, of the dent when the viscera are exposed. dorsal surface of the mantle, head and Male and female reproductive systems arms, consists of numerous well-spaced, were dissected. The penis is thick and small papillose warts; some of these, irregu- tubular with a proximal, recurved divertic- larly distributed, are more minutely papil- 286 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.2, 1978 a c Figure 6. Vosseledone clwrrua, new genus and species: a, spermatophore; b, penis; c, female geni- talia; d, egg. lated than the others. The warts are less octopods devoid of an ink sac and in which pronounced on the distal portion of the the esophageal crop is reduced or absent. arms. Two prominent papillose cirri occur This rules out the possibility of Vosseledone over the eye, of which the anterior is being congeneric with Bathypolypus Grimpe, smaller. The eyelids are densely papillated. 1921, Graneledone Joubin, 1918, Thau- The ventral surface of the mantle, head and meledone Robson, 1930, and Bentheledone arms is smooth. Robson, 1932. In addition, the degenerate In preservation in isopropyl alcohol, the radula of Vosseledone is distinctly different animals are of light flesh color. from that of BathypolYPllS, Graneledone, Measurements and indices for the seven and Bentheledone, where the rachidian specimens are given in Tables 1 and 2. tooth is simple and the lateral teeth are well differentiated. The degenerate radula of Type.-USNM 729454, male, mantle length Thaumeledone brevis (known in the litera- 49.0 mm. ture from two small CHALLENGER speci- Type locality.-35 °14'S, 52°28'W, east of mens from off Montevideo), and T. gunteri Punta del Este, Uruguay, in 200 m. (known from one small DISCOVERY fe- male collected in the South Georgia Islands), Discussion.-The new taxon described suggested the possibility that the material above cannot be placed in any of the under study might be conspecific with known genera of the Octopodinae, Bathy- either of these species, more likely T.
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