Taxonomic Reports of Otobothrioidea (Eucestoda, Trypanorhyncha) from Elasmobranch Fishes of the Southern Coast Off Brazil

Laboratório de Helmintos Parasitos de Vertebrados, Departamento de Helmintologia, Instituto Oswaldo Cruz-Fiocruz, Av. BrasilI 4365, 21045-900 Rio de Janeiro, RJ, Brasil *Laboratório de Inspeção e Tecnologia de Alimentos, Faculdade de Veterinária, Universidade Federal Fluminense, Niterói, RJ, Brasil **Laboratório de Biologia de Helmintos Otto Wucherer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil

nean region, Canada, Japan, New Zealand, and India and also from the musculature of Thyrsites sp. from Holland (Dollfus 1942, Bates 1990). In elasmobranchs, this species was reported from the spiral valve of Isurus oxyrinchus Rafinesque, 1810 in Japan and south California, US (Iwata 1939, Heinz & Dailey 1974.

MATERIALS AND METHODS
In March 1998, 30 elasmobranchs, 7 specimens (6 females and 1 male) of Heptranchias perlo, 87-107.4 cm in total length (tl), 16 specimens (10 females and 6 males) of Squalus sp., 41-67 cm (tl) and 7 specimens (1 female and 6 males) of Carcharhinus signatus, 120-150 cm (tl) were captured about 125 miles off the coast of the state of Paraná (25°50'S-25°52'S, 45°23'W-45°25'W; 200-500 m in depth), by professional fishermen of the Icanhema VI fish boat, and in March 1999, more 30 elasmobranchs, 18 females, and 12 males, of Prionace glauca, 206-287 cm (tl), were captured about 190 miles off the coast of the state of Santa Catarina (27°08'S-28°38'S, 45°30'W-46°53'W; ~ 25-50 m) by professional fishermen of the Kiyomã tuna fish boat. On board, stomachs and spiral valves, were collected, labelled and cooled on ice prior to examination. Cestodes were recovered, fixed, stained and mounted according to the technique of Amato et al. (1991). Taxonomic classification is in accordance with Campbell and Beveridge (1994). Measurements and terminology follow Dollfus (1942) and Campbell and Beveridge (1994). Measurements are in millimeters (mm) unless otherwise indicated. In the taxonomic summaries, the total number of parasitized specimens and the infrapopulation of each host are indicated. NH refers to new host and NGD to new geographical distribution; drawings were made with the aid of a drawing tube connected to a lightfield Olympus BH-2 microscope (LM). One specimen of M. horridus was observed under a variable pressure scanning electron microscope (VPSEM) -LEO 435; following this procedure, the same sample was routinely prepared and examined under a scanning electron microscope (SEM) -JEOL. Representative specimens were deposited in the Coleção Helmintológica do Instituto Oswaldo Cruz (CHIOC), Rio de Janeiro, Brazil; samples for comparison were also obtained from the CHIOC and from the Múseum National d'Histoire Naturelle, Paris (MNHN). At least one host specimen of each investigated fish species was deposited as symbiotypes sensu Brooks (1993) in the collection of the Instituto de Pesca, Santos, SP, Brazil and listed by Knoff et al. (2001a,b). Dollfus, 1942Grillotiidae Pintner,1969Progrillotia Dollfus, 1946Progrillotia dollfusi Carvajal & Rego, 1983 Hosts/site of infection: four specimens from the stomach of one male of Carcharhinus signatus (NH), one specimen from the spiral valve of one female of Heptranchias perlo (NH) and one specimen from the spiral valve of one female of Squalus sp. (NH). Locality: coast of the state of Paraná. Remarks: the six metacestodes studied agreed with the description of P. dollfusi (Carvajal & Rego 1983) and the redescription of Pereira Jr (1998), when this species was reported parasitizing sciaenid hosts in the littoral of the states of Rio de Janeiro and Rio Grande do Sul, respectively.

Otobothrioidea
The presence of this cestode species in C. signatus, H. perlo, and Squalus sp. represents new host records and the first reference in elasmobranchs.
Molicola horridus. Fig. 1: scolex. Fig. 2: tentacle 4, basal, corona of long hooks, with hooks 1 and 1', internal face on the left. Fig. 3: tentacle 3, basal, corona of long hooks, with hooks 1 and 1'. Metabasal, half-spiral of principal rows, internal face on the right, and band of small hooks, external face. VPSEM, and SEM, permitted the establishment of the distribution pattern of these hooks around the tentacle. On the basis of the illustrations of this species after Dollfus (1942) only the basal corona of one of the tentacles can be observed, with hook one central, four long hooks and two smaller in a half-turn, what is equivalent to the pattern of the tentacles one and two observed in the Brazilian specimens. The description of these long basal hooks by Dollfus (1942) is general: "...vient ensuite une région portant de très longs crochets, beaucoup plus longs que ceux implantés antérieurement. Ces longs crochets, généralement au nombre de 9, ne sont pas tous de même longueur et sont accompagnés de quelques-uns (2 ou 3) beaucoup plus petits. Ces longs crochets ont une forme peu arquée et leur pointe n'est pas aiguë; ils s'insèrent sur les faces bothridiale et antibothridiale et sur le côté interne de la trompe ( fig. 291); il n'y en a pas du côté externe ( fig. 292)..."; at the bottom of the page the author comments about the difference in the number of these hooks after previous data.
Under VPSEM and SEM the pattern of distribution of the hooks in the basal corona, the presence of pores in these hooks and papillae around the genital pore are added to the original description.
The finding of the species in P. glauca represents a new host record and its first occurrence in Brazil.