Camallanus maculatus n. sp. (Nematoda: Camallanidae) in an ornamental fish Xiphophorus maculatus (Osteichthyes: Poeciliidae) cultivated in São Paulo State, Brazil

The present study describes Camallanus maculatus n. sp. (Nematoda: Camallanidae) from Xiphophorus maculatus (Osteichthyes: Poecilidae) collected in an ornamental fish farm in São Paulo State, Brazil. Thirty-three out of 40 examined fish were parasitized (82 percent prevalence) with mean intensity of 2.8 (1-20). Male specimens were 3,500µm total length and females 7,100µm total length, provided with orange-brown buccal capsule and two developed tridents. Males showed two unequal spicules, gubernaculum absent and females with vulva situated in the middle of the body. The main characteristics were the sleekly longitudinal ridges in the buccal capsule in both sexes, enlargement at the anterior end of the smaller spicule, the number of genital papillae, longer muscular and glandular portion of esophagus and round tail in female

Descreve-se Camallanus maculatus n. sp. (Nematoda: Camallanidae) em Xiphophorus maculatus (Osteichthyes: Poecilidae) capturado em uma piscicultura ornamental no estado de São Paulo. De 40 peixes examinados, 33 estavam parasitados (prevalência de 82 por cento) cuja intensidade média foi de 2,8 (1-20). Os machos apresentaram 3.500µm e as fêmeas com 7,100µm de comprimento total, providos de uma cápsula bucal laranja-castanho e dois tridentes. Observaram-se machos com espículos desiguais, gubernáculo ausente e fêmeas com vulva situada na metade do corpo. As principais características foram as estrias longitudinais lisas em cada valva da cápsula bucal em ambos os sexos, o espículo menor com alargamento na extremidade anterior, o número de papilas genitais, as porções muscular e glandular do esôfago longas e a cauda longa e arredondada na fêmea

Pathobiology associated with the spiruroid nematodes Camallanus oxycephalus and Spinitectus carolini in the intestine of green sunfish, Lepomis cyanellus.

The histopathology induced by Camallanus oxycephalus and Spinitectus carolini in the intestine of green sunfish Lepomis cyanellus was examined. At what is assumed to be more recent attachment sites, penetration of C. oxycephalus was restricted to the mucosal layer, causing complete destruction of the columnar epithelium. At what appeared to be older attachment sites, the parasite penetrated deep into the intestinal wall, even to the circular muscle layer. At these sites of attachment, there were flask-shaped ulcers in the mucosal and submucosal layers. Surrounding the ulcers, there was granulomatous tissue, with extensive fibrosis at the surface; the fibrosis probably reduced the loss of body fluids and blood cells from the intestinal wall. The number of goblet cells in the posterior end of the intestine increased significantly, from 92.6 cells/mm in uninfected fish to 168.4 cells/mm in fish infected with more than 5 C. oxycephalus. Adult S. carolini also causes severe damage to the intestinal wall of green sunfish. Parasite penetration was not limited to the mucosal layer. Mature worms were observed invading both the muscular and serosal layers. Penetration by the parasite was usually associated with the local loss of columnar epithelium and infiltration by lymphocytes and granulocytic leukocytes. Fibrosis in the mucosal layer was commonly observed. There was goblet cell hyperplasia in the anterior portion of the intestine, with numbers of goblet cells increasing from 64.4 cells/mm in uninfected fish to 95.0 cells/mm in heavily infected fish.