Benedenia ernsti Deveney & Whittington, 2010, n. sp.
Creators: name: Deveney, Marty R.
name: Whittington, Ian D.
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Platyhelminthes
Monogenea
Capsalidea
Capsalidae
Benedenia
Benedenia ernsti

description: Benedenia ernsti n. sp.
(Figs. 1, 2)
Type host and locality: Symphorus nematophorus (Bleeker) (Perciformes: Lutjanidae), Heron Island (23°27ˏS, 151°55ˏE), Queensland, Australia.
Other host and locality: Lutjanus sebae (Cuvier) (Perciformes: Lutjanidae), Heron Island (23°27ˏS, 151°55ˏE), Queensland, Australia.
Site on host: Gills, including branchial arches.
Holotype: QM G 218907 (1 slide, 2 specimens, 1 holotype, 1 paratype [marked]) ex gills Symphorus nematophorus.
Paratypes: QM G 218908–13 (5 slides, 6 specimens) ex gills Symphorus nematophorus; QM G 218918 (1 slide, 1 specimen) ex gills Lutjanus sebae.
Voucher specimens: QM G 218914–7 (4 slides, 4 specimens) ex gills Symphorus nematophorus; QM G 218919–21 (3 slides, 3 specimens) ex gills Lutjanus sebae.
Etymology: The specific name is in honour of Dr Ingo Ernst, who discovered the first specimens of this species during his work at Heron Island Research Station in the late 1990s.
Description and observations: Based on studies of 3 live specimens and 10 wholemounts of preserved, sexually mature specimens. Measurements from 8 preserved adult specimens. Total length including haptor 1919–2542 (2266); maximum breadth 583–808 (697) at level of testes (Fig. 1 A). Haptor elliptical, 468–619 (557) long, 381–480 (439) wide. Accessory sclerite 109–144 (116) long with pointed, recurved distal region (Fig. 1 A, C). Anterior hamulus 108–133 (121) long, slender with blunt distal tip and subterminal, ventrallydirected spike (Fig. 1 A, D). One anterior hamulus missing in 2 specimens. Posterior hamulus 60–94 (73) long, root and shaft with ventral thin flattened wing-like structure, distal tip hooked (Fig. 1 A, E). Fourteen peripheral hooklets, sickle-shaped, each 6–9 (8) long (n=10 from specimen prepared in lactic acid). Marginal valve scalloped with consistent pattern of lobes between hooklets on each side of haptor: 3 lobes between hooklets of pair II on posterior border of haptor; 2 lobes between hooklets II and position of posterior hamuli; 2 lobes between posterior hamuli and hooklets of pair III; 3 lobes between hooklets III and IV and between hooklets IV and V; 5 lobes between hooklets V and VI; 7 lobes between hooklets VI and VII; 10 lobes between hooklets VII and VIII; 14 lobes between hooklets of pair VIII on anterior border of haptor (Fig. 1 A).
Anterior attachment organs approximately circular, 210–266 (224) in diameter. Three adhesive zones (reported in other Benedenia spp. e.g. Whittington & Kearn 1993) not observed in live or preserved material. Pharynx 132–170 (146) long, 149–190 (170) wide. Two pairs of eyespots, pigment shielded, dorsal, between pharynx and anterior margin of body. Unclear whether gut caeca confluent posteriorly.
Glands of Goto in posterior angle between testes (Fig. 2). Vas deferens swells to form seminal vesicle between testes and germarium (Fig. 2). Vas deferens joins penis canal dorsally. Vas deferens and duct of male accessory gland reservoir twisted together along length of penis in regular braid-like pattern (Fig. 2). Vas deferens and duct of accessory gland reservoir join near distal tip of penis. Duct of accessory gland reservoir with large, muscular bulb-like swelling with wide lumen (Fig. 2). Distal tip of penis armed with elongate, conical sclerite with serrated distal tip (Fig. 1 B, 2). Unclear whether sclerite is gutter-shaped or tubular. Penis protrusible via common genital duct and common genital pore. Large, rounded lobe on left body margin near common genital pore (Fig. 1 A, 2).
Germarium globular, compact with large internal fertilisation chamber (Fig. 2). Uterus short (Fig. 1 A, 2). Vaginal opening on dorsal surface, posterior to left testis, approximately one-third to one half the distance between testes and anterior haptor margin. Vaginal pore muscular, cup-like, surrounded by large region of glandular tissue. Vaginal duct very narrow, expands anteriorly to form seminal receptacle at level of vitelline reservoir. Seminal receptacle communicates with vitelline reservoir by short, narrow duct. Vitelline follicles extend in body proper from level of pharynx posteriorly to haptor peduncle (Fig. 1 A). Eggs tetrahedral with long appendage at one non-opercular pole.
Comments and differential diagnosis: Benedenia ernsti is distinctive. The position of the vaginal pore and the surrounding glandular tissue are unique among benedeniines. The location of the vaginal pore further expands the range of known anatomical relationships between the vaginal and common genital pores as described by Whittington et al. (2001, see their fig. 12). Benedenia ernsti can be distinguished from all other species of Benedenia by this feature alone, but is also characterised by the distally recurved accessory sclerites, presence of a very large single lobe dorsal to the common genital pore, a muscular bulb on the duct of the accessory gland reservoir within the penis and a conical sclerite with distal striations at the distal tip of the penis. Only Benedenia rohdei Whittington, Kearn & Beverley-Burton, 1994 also possesses a penis armed with a sclerite. The muscular bulb on the duct of the accessory gland reservoir of B. ernsti is distinctive, although a similar structure is observed in the penis of Benedenia jaliscana Bravo-Hollis, 1952 (see Whittington et al. 2001, their fig. 24A).
description: Published as part of Deveney, Marty R. & Whittington, Ian D., 2010, Three new species of Benedenia Diesing, 1858 from the Great Barrier Reef, Australia with a key to species of the genus, pp. 1-22 in Zootaxa 2348 on pages 2-5, DOI: 10.5281/zenodo.275591