Phthinomita poulini, Nolan & Cribb, 2006

Nolan, Matthew J. & Cribb, Thomas H., 2006, An exceptionally rich complex of Sanguinicolidae von Graff, 1907 (Platyhelminthes: Trematoda) from Siganidae, Labridae and Mullidae (Teleostei: Perciformes) from the Indo-west Pacific Region, Zootaxa 1218 (1), pp. 1-80 : 61-64

Phthinomita poulini n. sp. ( Figs. 50–62 )

Type host: Parupeneus barberinus (Lacepède) , Dash­dot Goatfish ( Perciformes : Mullidae ).

Other hosts: P. bifasciatus (Lacepède) , Doublebar Goatfish; P. cyclostomus (Lacepède) , Goldsaddle Goatfish. ( Perciformes : Mullidae ).

Type locality: Lizard Island, northern Great Barrier Reef (14°40’S 145°27’E), Queensland .

Material examined: ex P. barberinus, Lizard Island (QLD), Aug. 2002, Jan. 2003, May. 2004, eight specimens (Holotype no. QM G 225634 ; Paratype nos. QM G 225635–225637 ) (another three specimens for scanning electron microscopy, eleven sequenced for ITS2); ex P. bifasciatus, Lizard Island (QLD), Aug. 2002, (two specimens sequenced for ITS2); ex P. cyclostomus, Lizard Island (QLD), May 2004, three specimens (Paratype nos. QM G 225638–225639 ), (another six specimens sequenced for ITS2) .

Collector: M.J. Nolan.

Etymology

Specific name for Dr Robert Poulin in honour of his contributions to the field of parasite ecology.

Description

Based on 11 whole mounts. With features of genus. Body notched level with male genital pore. Vestigial oral sucker bearing six concentric rows of fine spines. Tegumental papillae extend anteriorly to near posterior margin of female genital pore, extend posteriorly past posterior margin of male genital pore. Anterior testis originating at posterior end of intercaecal field, ventral to posterior caeca, margins lobed. Posterior testis ovoid. Cirrus­sac spherical to tear­shaped. Internal seminal vesicle spherical, occupying entire region of cirrus­sac; ejaculatory duct straight; prostatic cells not seen. Ovary ovoid or spherical, slightly overlapping posterior margin of anterior testis. Oviduct originating at centre of posterior margin of ovary, straight. Vitelline duct forming posterior to posterior margin of ovary, sinuous; vitelline reservoir forming anterior to anterior margin of cirrussac, sinuous, entering oötype postero­dorsally. Oötype ovoid, medial. Mehlis’ gland extending anteriorly to posterior margin of cirrus­sac, extending posteriorly just past posterior margin of vitelline reservoir (not as far as anterior margin of posterior testis). Uterus extending from oötype, sinuous. Uterine chamber forming laterally to posterior margin of ovary, sinuous, thin anteriorly, widening posteriorly, narrowing again before passing dorsally to female genital pore. Vitelline follicles extending anteriorly past intestinal bifurcation, extending posteriorly past posterior margin of ovary (to mid­section of uterine chamber), filling intercaecal field, passing posteriorly medially.

Remarks

This species is differentiated from its congeners by possessing the combination of a body 2350–4269 (3451) long, a vestigial oral sucker bearing six concentric rows of fine spines, tegumental papillae (associated with the genital pores) that do not extend anteriorly past the posterior margin of the female pore, an anterior testis that is positioned in the posterior end of the intercaecal field and occupies 35–40% of the body length and a posterior testis that occupies 32–64% of the body width. Phthinomita poulini differs further in having a spherical cirrus­sac 1.6–12.8 times longer than wide, a uterine chamber that originates laterally to the posterior margin of the ovary and is 183–273 (226) x 22–45 (34) and vitelline follicles that extend anteriorly past the intestinal bifurcation.

There are in addition, 1–33 base differences (0.3–10.0% sequence divergence) between the ITS2 rDNA sequence of P. poulini and those of the remaining Phthinomita species sequenced here.

Figures

FIGURE 50. A,B. Phthinomita poulini n. sp. from the ventricle (heart) of Parupeneus barberinus off Lizard Island. Adult. Dorsal anteriorly, medially twisting laterally at level of “arrow a”, ventral side to the right, whole mount. Scale­bar: 250 m.

FIGURES 51–52. Phthinomita poulini n. sp. 51. Male terminal genitalia, lateral view. 52. Female terminal genitalia, lateral view. Scale­bars: 51, 100 m; 52, 250 m. Site in host: Intertrabecular spaces of ventricle (heart).

FIGURES 53–57. Phthinomita poulini n. sp. 53,54,55. Vestigial oral sucker delimited posteriorly by constriction of body wall (internally separated from body by septum); sucker bearing 5 concentric rows of fine spines. Mouth opens posterior to last spine row. 56. Tegumental spines in incomplete transverse rows, 3–6 spines per row. Run entire length of body. 57. Tegumental spines covered in tegument or mucus. Abbreviations: BC, body constriction; M, mouth. Scale­bars: 53,55,57,1 m; 54,56,10 m.

FIGURES 58–66. Phthinomita poulini n. sp. 58,59,60. Male genital pore at apex of notch in posterior of body. Female genital pore antero­dextral to male pore. Only male pore surrounded by tegumental papillae. 61,62. Excretory pore opening terminally. Abbreviations: FGP, female genital pore; MGP, male genital pore; TP, tegumental papillae. Scale­bars: 58,59,61, 10 m; 60,62, 1 m.