Benedenia elongata ( Yamaguti, 1968 ) Egorova, 1997

Whittington, I. D., Deveney, M. R. & Wyborn, S. J., 2001, A revision of Benedenia Diesing, 1858 including a redescription of B. sciaenae (van Beneden, 1856) Odhner, 1905 and recognition of Menziesia Gibson, 1976 (Monogenea: Capsalidae), Journal of Natural History 35 (5), pp. 663-777 : 690-694

Benedenia elongata ( Yamaguti, 1968) Egorova, 1997

(®gure 17)

Synonyms. Pseudobenedenia elongata Yamaguti, 1968 ; Parabenedenia elongata ( Yamaguti, 1968) Gibson, 1976 ; Menziesia elongata ( Yamaguti, 1968) Gibson, 1976 ; Benedenia kintoki Iwata, 1990 (new synonym).

Material studied. USNPC: No. 63590 (SY No 91) (holotype of Pseudobenedenia elongata ) (1 slide, 1 specimen) ex gills of Priacanthus boops (Forster in Bloch and Schneider) (5 Cookeolus boops Schneider , see Smith and Heemstra, 1995 and Eschmeyer, 1998 for discussion) ( Priacanthidae ) from Hawaii. We could trace no specimens that Yamaguti collected from lutjanid ®shes ( Yamaguti, 1968). FU: No. M 0004 (holotype of B. kintoki ) (1 slide, 1 specimen) ex gills of Cookeolus boops (Priacanthidae) from Coast of Hukuoka Prefecture, Japan.

Observations. Yamaguti (1968) ascribed this species to Pseudobenedenia which subsequently became Parabenedenia (see Gibson, 1976a) and then Menziesia (see Gibson, 1976b) before Egorova (1997) incorporated all species of Menziesia into Benedenia . Iwata (1990) described B. kintoki also from Cookeolus boops in Japan. We have examined the holotypes of B. elongata and B. kintoki and conclude that these species are synonymous. Yamaguti’s material has`wavy’ proximal ends to the anterior and posterior hamuli (®gures 17F, G), but we suspect that this may have been an artifact of handling or ®xation. In all other aspects, these two species appear identical and are recorded from the same host species. Iwata’s specimen is excellent and has allowed much to be elucidated about this species which we could not observe in the available specimen of Yamaguti. Benedenia elongata is 1.3± 4 mm long (i.e. small to medium-sized; ®gure 3), with small, ellipsoid anterior attachment organs. The haptor is sub-circular (®gure 17A). We were unable to determine the relationship between the lobes of the marginal valve and the hooklets because hooklets are not visible in Yamaguti’s specimen and Iwata’s specimen is damaged such that details of the lobes are di cult to see. The marginal valve is fairly uniform in width (®gure 17A). The reproductive organs were described adequately by Yamaguti (1968). The penis is thin and tapers distally and the vas deferens and the duct of the accessory gland reservoir join near the distal tip of the penis. This species is distinctive because the germarium is widely spaced from the testes (®gure 17A). The vitellarium extends anteriorly only as far as the posterior third of the pharynx and the body proper anterior to the pharynx is ®lled with ®ne gland cells.

Type-host and locality. Priacanthus boops (5 Cookeolus boops ) ( Priacanthidae ), Hawaii.

Published records and descriptions. Yamaguti (1968); Iwata (1990).

Published host records. Lutjanidae : Pristipomoides sieboldii (Bleeker) ; Arnillo auricilla ( Jordan, Evermann and Tanaka) (5 Pristipomoides auricilla Jordan, Evermann and Tanaka, see Kyushin et al., 1977) (see Yamaguti, 1968); Priacanthidae : Cookeolus boops (see Iwata, 1990), Priacanthus boops (5 Cookeolus boops ) (see Yamaguti, 1968).

Site . Gills.

Distribution. Hawaii ( Yamaguti, 1968); Coast of Hukuoka Prefecture, Japan ( Iwata, 1990).

Remarks. From our observations of type material, we are con®dent the species described as B. kintoki by Iwata (1990) is B. elongata . Benedenia elongata is most similar to B. epinepheli and Yamaguti’ s four Hawaiian Benedenia species. We retain it in Benedenia as proposed by Egorova (1997) because the penis is not as long nor as curved as that in Menziesia species and the accessory gland reservoir lies in the same plane as the proximal part of the penis. Benedenia elongata can be diOEerentiated from B. epinepheli because B. elongata has no obvious lobes associated with the common genital pore or vaginal pore. Benedenia elongata has ellipsoid anterior attachment organs which diOEerentiate it from B. bodiani , B. hawaiiensis and B. lolo . Although some specimens of B. scari have anterior attachment organs which are bipartite, disc-shaped and well set oOE from the body, others have anterior attachment organs similar to those of B. elongata (®gure 17). Benedenia elongata is best

FIG. 17. Benedenia elongata . (A) Whole animal, ventral view; composite drawing from all available specimens (see text for details). No hooklets shown on haptor because of the poor quality of the specimens examined. Scale bar 5 750 Mm. (B) Accessory sclerite; (C) anterior hamulus; (D) posterior hamulus all drawn from FU: No. M 0004. (E) Accessory sclerite; (F) anterior hamulus; (G) posterior hamulus all drawn from USNPC: No. 63590. Scale bar 5 50 Mm. Note that Yamaguti’s specimens show curvature of the haptoral sclerites not observed in Iwata’s material and we consider it possible that this is an artifact of preservation and / or processing. Gl, gland cells anterior to pharynx.

diOEerentiated from B. scari by the relative sizes of the sclerites: in B. elongata , the accessory sclerites are large with a hooked distal tip; the anterior hamuli have a ®ne shaft and a thicker, recurved distal tip; the posterior hamuli have a small ®ne hook and an alate shaft (®gure 17D, G) while in B. scari the accessory sclerites are reduced in size and the anterior and posterior hamuli are larger and broader (®gure 19N, O).