Cardicola bartolii, Nolan & Cribb, 2006

Nolan, Matthew J. & Cribb, Thomas H., 2006, Cardicola Short, 1953 and Braya n. gen. Digenea: Sanguinicolidae) from five families of tropical Indo-Pacific fishes (, Zootaxa 1265 (1), pp. 1-80 : 26-29

Cardicola bartolii n. sp.

( Figs 23–26 )

Type host: Siganus lineatus (Valenciennes) , Goldlined Rabbitfish ( Perciformes : Siganidae ).

Other hosts: S. corallinus (Valenciennes) , Coral Rabbitfish ( Perciformes : Siganidae ).

m; 24–26, 100 m.

Site in host: Sinus venosus, bulbus arteriosus (heart), and gills.

Type locality: Heron Island, southern Great Barrier Reef (23º26’S 151º54’E), Queensland .

Material examined: ex S. lineatus, Heron Island (QLD), Apr. 2001, Feb. 2002, Feb. 2005, two specimens (nos. QM G 225225–225226 ) (two specimens sequenced for ITS2) ; ex S. corallinus, Heron Island (QLD), Feb. 2002, one specimen (no QM G 225227 ) .

Prevalence of infection: Three of twenty­six S. lineatus from Heron Island infected with four specimens ; one of thirty­one S. corallinus from Heron Island infected with one specimen .

Collector: M.J. Nolan.

Etymology

Specific name for Dr Pierre Bartoli, for his contributions to the field of digenean systematics through his studies of Mediterranean fishes.

Description

Based on three whole mounts. With features of genus. Body elliptical, 661–912 (786) x 116–172 (151), 5.5–5.7 times longer than wide ( Figure 23 ). Tegumental spine rows 6–13 (9) wide, width consistent along margin, 5 spines per row. Nerve chords conspicuous; nerve commissure 67–83 (75) or 7–13% of body length from anterior end. Oral sucker vestigial, rhomboidal, 16–21 (19) x 16–21 (19), delimited posteriorly by fine membrane, bearing unknown number of concentric rows of fine spines ( Figure 24 ). Mouth 5–10 (7) from anterior end. Oesophagus sinuous, narrow anteriorly, widening posteriorly to posterior margin of nerve commissure, posterior half surrounded by gland cells, 372–483 (431) or 48–56% of body length. Intestine X­shaped; anterior caeca unequal, right anterior caecum 34–151 (84) long, left anterior caecum 40–131 (79) long, length 10–14% of body length, wider than posterior pair; posterior caeca unequal, thin, convoluted, right posterior caecum 185–369 (264) long, left posterior caecum 178–362 (271) long, length 27–40% of body length, 2.7–2.8 times longer than anterior pair, terminal extremities expanded. Testis extending anteriorly and laterally to intercaecal field, terminating before posterior margins of posterior caeca, 265 or 29% of body length x 96–112 (104) or 67% of body width, 2.4 times longer than wide, dorsal to posterior caeca except anterior left margin, which is ventral. Vas deferens originating at posterior margin of testis, passing posteriorly sinuously, expands distally to form seminal vesicle. Seminal vesicle elliptical, 85–106 (95) or 12–13% of body length from posterior end, 52–74 (63) x 32–45 (38), 1.6–1.7 times longer than wide ( Figure 25 ). Ejaculatory duct curved, directed postero­dorsally; prostatic cells small. Male genital pore sub­marginal. Ovary bilobed, posterior to and abutting posterior margin of testis, intercaecal anteriorly, posteriorly extending past intercaecal field, dorsal to vas deferens, 39–48 (43) or 4–7% of body length x 29–116 (72) or 25–69% of body width, 215 or 24% of body length from posterior end. Oviduct originating at centre of posterior margin of ovary, passing sinistrally before looping ventrally, expanding to form oviducal seminal receptacle, narrowing anteriorly to anterior margin of seminal vesicle, continuing posteriorly as narrow tube, joining with vitelline duct lateral to seminal vesicle. Oviducal seminal receptacle tear­shaped, posterior to and abutting posterior margin of ovary, 48 x 22, 2.1 times longer than wide. Vitelline duct seen anteriorly to anterior margin of anterior caeca, passing posteriorly ventral to oesophagus, intestine, testis, ovary, oviducal seminal receptacle, oviduct and vas deferens, expanding to form vitelline reservoir lateral to posterior margin of ovary. Oötype elliptical to ovoid, lateral to posterior margin of seminal vesicle, 16–32 (24) x 11–22 (17). Mehlis’ gland extending anteriorly past posterior margin of seminal vesicle, posteriorly extending to posterior margin of uterus. Uterus passing posteriorly from oötype, looping antero­dorsally as convoluted tube to level of oötype, anterior to oötype continues antero­dextrally sinuously (but not convoluted), dorsal to vitelline reservoir, oviduct and vas deferens, lateral to oviducal seminal receptacle passes sinistrally across midline, dorsal to ovary, curving dextrally to metraterm ( Figure 26 ). Metraterm passing dorso­posteriorly, 48–64 (56) x 11. Female genital pore opening dorso­medially, lateral to posterior margin of oviducal seminal receptacle, anterior to seminal vesicle, antero­dextrally to male genital pore. Eggs elongate, 22–39 (31) x 10–22 (17) wide (n=3). Vitellarium follicular, anteriorly extending past nerve commissure, posteriorly extending to posterior margin of ovary, anteriorly dorsal to lateral nerve chords, both dorsal and ventral to oesophagus, intestine and testis, posteriorly ventral to ovary. Excretory vesicle obovate, 5–10 (7) in diameter; collecting ducts seen extending anteriorly to posterior extremity of Mehlis’ gland. Excretory pore terminal.

Remarks

This species shows close affinity to the genus Cardicola and is distinguished from its congeners in having the combination of a body 5.5–5.7 times longer than wide, an oral sucker, an oesophagus that is sinuous, posterior caeca that are convoluted and 2.7–2.8 times longer than the anterior pair, a testis that is mostly intercaecal (extending anteriorly and laterally but not posteriorly) is, in part, ventral to the posterior caeca, is 2.4 times longer than wide and has a width that is 67% of the body width. The new species differs further from its congeners in having a bilobed ovary that is positioned 24% of the body length from the posterior end, is anteriorly intercaecal and is medial, a uterus that extends posteriorly from the oötype before looping anteriorly and is entirely posterior to the posterior caeca (in contrast to that in Cardicola ahi ), an oviducal seminal receptacle that is posterior to the intercaecal field and a female genital pore that opens laterally to the posterior margin of the oviducal seminal receptacle.

Cardicola bartolii n. sp. appears most similar to C. covacinae n. sp. but differs in having vitelline follicles that extend to the posterior margin of the ovary rather than to the level of the male genital pore.

Figures

FIGURES 23–26. Cardicola bartolii n. sp. from the sinus venosus and bulbus arteriosus (heart), and gills of Siganus lineatus off Heron Island. 23. Adult, whole mount, ventral view. Only species so far found with uterus that is not convoluted anterior to oötype (distally). 24. Anterior region, ventral view, showing vestigial oral sucker delimited by fine membrane and body constriction, and the nerve commissure. 25. Male terminal genitalia, ventral view. 26. Female terminal genitalia, ventral view. Vitelline duct and vitelline reservoir omitted from figure as they obscure the path of the oviduct, oviducal seminal receptacle and uterus as they pass posteriorly. Scale­bars: 23, 250