Oochoristica noronhae, Bursey, Charles R., Rocha, Carlos Frederico D., Menezes, Vanderlaine A., Ariani, Cristina V. & Vrcibradic, Davor, 2010

Bursey, Charles R., Rocha, Carlos Frederico D., Menezes, Vanderlaine A., Ariani, Cristina V. & Vrcibradic, Davor, 2010, New species of Oochoristica (Cestoda; Linstowiidae) and other endoparasites of Trachylepis atlantica (Sauria: Scincidae) from Fernando de Noronha Island, Brazil, Zootaxa 2715, pp. 45-54 : 46-47

Oochoristica noronhae n. sp.

( Figs. 1–4 )

Type host. Trachylepis atlantica (Schmidt) , Noronha skink ( Scincidae ) Symbiotype: MNRJ 19047; collected on 29 October 2005.

Type locality. Fernando de Noronha island, Brazil (3º 51’ S; 32º 25’ W).

Site of infection. Small intestine.

Type specimens. Holotype, USNPC 103503; paratypes, USNPC 103504;

Etymology. The new species is named for its collection locality.

Description. With characters of the genus: scolex with 4 suckers and without rostellum or armature; proglottids acraspedote; genital pores irregularly alternating; genital ducts lie between osmoregulatory canals; uterus ephemeral; testes posterior to vitellarium.

Based on 5 intact specimens. Total length 23–29 mm; proglottid number 46–54; 10–18 immature proglottids, wider than long; 14–19 mature proglottids, isodiametric to longer than wide; 17–24 gravid proglottids, longer than wide; maximum width of strobila, 0.15–0.20 mm. Scolex, distinctly set-off from neck, 0.83–1.02 mm wide; with four circular suckers, 140–158 µm in diameter; neck length, 0.64–0.76 mm. Excretory system of four longitudinal ducts visible throughout length of strobila; genital pores irregularly alternating, situated in anterior quarter of proglottid; genital atrium, 30 µm wide, 30 µm deep; cirrus sac length, 85–140 µm, width 18–24 µm; vagina immediately posterior to vas deferens. Ovary on midline divided into 2 lobes, each subdivided into 8–10 lobules; ovary width 43–61 µm; vitelline gland on midline behind ovary, width 21–27, length 31–42 µm; ootype and Mehlis’ gland complex between ovary and vitelline gland. Testes lie posterior to vitelline gland in a single field; testes number 18–26 per proglottid. In gravid proglottids uterine capsules, 43–49 µm in diameter, each contain a single egg; oncosphere, 27–34 µm in diameter, oncospheal hook 17–20 µm in length. Vagina, vas deferens, and cirrus pouch visible in gravid proglottids. On average 110– 130 eggs in terminal proglottid, eggs not occurring lateral of excretory ducts.

Remarks. The 88 species currently assigned to Oochoristica that infect reptiles are presented in Table 2 (data were taken from original papers). One additional species is known, Oochoristica eremophilia Beveridge from the marsupial mammal Antechinus rosamondae Ride (Dasyuridae) from Australia ( Beveridge 1977). Of the 14 neotropical species (Table 2) only two, namely O. parvula and O. vanzolinii have circular suckers and fewer than 30 testes per proglottid, as does O. noronhae n. sp. These species can be separated on the basis of number of lobules per ovarian lobe; in O. vanzolinii the ovarian is entire, O. parvula has 3–5 lobules/lobe, O. noronhae has 8– 10 lobules/lobe. In addition, the scolex of O. noronhae is distinctly set off from the neck, while the scolex of O. parvula is of similar width to the neck. Of the remaining 74 species, 17 also have circular suckers and testes numbering 30 or less, namely O. novaezealandae (from Australian realm), O. jonnesi and O. najdei (from Ethiopian realm), O. macallisteri (from Nearctic realm), O. aulicus , O. celebesensis , O. excelsa , O. hemidactyli , O. javaensis , O. junkea , and O. lygosomatis (from Oriental realm), O. brachysoma , O. elongata , O. feliui , O. japonensis , O. okinawaensis , and O. sobolevi (from Palaearactic realm). These species differ from O. noronhae n. sp. in the following ways. In O. brachysoma , O. hemidactyli , O. japonensis , O. okinawaensis , and O. najdei , the testes occur in two clusters. In O. elongata , O. excelsa , O. junkea , and O. novaezealandae , the ovarian lobes are not subdivided into lobules; while in O sobolevi each ovarian lobe consists of more than 24 lobules. Oochoristica celebesensis and O. feliui have scoleces greater than 500 µm in diameter. The suckers of O. javaensis are less than 100 µm in diameter. Oochoristica lygosomatis has one pair of osmoregulatory canals. In O. jonnesi and O. aulicus , the cirrus pouch is greater than 150 µm in length. In O. macallisteri , the scolex is not distinctly set off from the neck.

Figures

FIGURES 1 – 4. Oochoristica noronhae n. sp. 1. Scolex. 2. Mature progottid. 3. Oncosphere. 4. Terminal, gravid proglottid. Scale bar in micrometers.