ON THE OCCURRENCE OF Haplometroides buccicola ( TREMATODA , DIGENEA , PLAGIORCHIIDAE ) INFECTING Phalotris lativittatus ( SERPENTES , COLUBRIDAE ) IN BRAZIL

Haplometroides buccicola (Trematoda, Digenea, Plagiorchiidae) was reported in the mouth and oesophagus of Phalotris lativittatus (Serpentes, Colubridae) from Botucatu, São Paulo State, Brazil. This is the first report on the occurrence of H. buccicola parasitizing P. lativittatus. The Haplometroides genus was also discussed and the most important morphological characters for the identification of the species H. buccicola and H. odhneri are presented.


INTRODUCTION
The parasitology of Brazilian snakes has been under study for an extensive period of time.Travassos et al. (12) wrote an important revision on Brazilian trematodes.Since then, few studies on trematodes of Brazilian snakes have been published (1,2,3,4,9,10,11).
There are no reports on the occurrence of trematodes parasitizing snakes of the Phalotris genus, and few hosts for species of Haplometroides are known.Thus, the aim of this study was to report the occurrence of Haplometroides buccicola (Trematoda, Digenea, Plagiorchiidae) in a specimen of Phalotris lativittatus (Serpentes, Colubridae).
The voucher host snake was from the city of Botucatu, São Paulo State, Brazil.This animal was properly preserved and deposited in the Herpetological Collection of the Center for the Study of Venom and Venomous Animals of the São Paulo State University.This snake was necropsied and eight trematodes were collected from the mouth and oesophagus.These trematodes were transferred to AFA solution without compression.Three of them were stained with carmine, clarified with creosote, and mounted in Permount resin.Morphometric analysis was performed, using the Leica Qwin Lite 2.5 computerized system.All measurements are reported as the mean and range (minimum-maximum) for the three specimens.
The characteristics of the trematodes (Figure 1 Phalotris lativittatus was described by Ferrarezzi (5).There are no reports on the occurrence of helminthes in this snake species, so the present study is the first note on this subject.Further, this is the first report on the occurrence of a trematode of the genus Haplometroides in a snake from the family Colubridae.Previous studies showed its presence only in snakes of the families Elapidae, Boidae, and Leptotyphlopidae (6,7,8,9,11).
According to Ruiz and Perez (8), the species H. odhneri is slightly different from H. buccicola.The former presents: 1) smaller dimensions, 2) a shorter oesophagus, 3) a tegument presenting less spines, 4) more compact vitellines, which are distributed from the oesophagus region to the ovarian region, 5) broader eggs, 6) a more lateral genital pore, and 7) a less developed acetabulum, where the relation between it and the oral sucker is smaller in the case of H. odhneri than in the case of H. buccicola.PLAGIORCHIIDAE) INFECTING Phalotris lativittatus (SERPENTES, COLUBRIDAE) IN BRAZIL.J. Venom.Anim.Toxins incl.Trop. Dis., 2005, 11, 3, p.376 Comparing the data of Ruiz and Perez (8) with that of the specimens described by Silva and Barrella (9), Silva et al. (11), and the trematodes of the present paper, it was our conclusion that among the characteristics cited, the position of the vitelline follicles is the only useful characteristic that helps differentiate the two species of the genus Haplometroides.Another, not cited by Ruiz and Perez (8), is the length of the intestinal caecum.Therefore, we conclude that for the species identification of the Haplometroides genus, the following should be considered: H. buccicola presents vitellines, which are distributed from the zone of caecum bifurcation to the zone of the posterior testis, and the intestinal caecum extends up to or beyond the zone of the posterior testis.In contrast, H. odhneri presents vitelline follicles, which are distributed from the oesophagus region to the ovarian region, never reaching the testicular zone, and the intestinal caecum extends up to the zone of the anterior testis, never reaching the posterior one.
According to these criteria, we reviewed the H. odhneri reported by Silva and Barrella (9) and Silva et al. (11), and concluded that the species reported by these authors was H. buccicola.