Aploparaksis (Aploparaksis) rissae Schiller, 1951

Bondarenko, Svetlana & Kontrimavichus, Vytautas, 2006, Cestodes of the genus Aploparaksis Clerc, 1903 (Cyclophyllidea, Aploparaksidae) reported from gulls, with a description of new species, Journal of Natural History 40 (47 - 48), pp. 2589-2610 : 2596-2597

Aploparaksis (Aploparaksis) rissae Schiller, 1951

( Figure 4 )

Synonyms: Aploparaksis filiformis Spassky, 1963, pp. 144–146 , Figures 37–38 not Aploparaksis filiformis of Hromada and Macko, 1995, pp. 59–60, Figure 4 .

Aploparaksis daviesi Deblock and Rausch, 1968, pp. 436–437 , Figure 4 .

Hosts. Rissa tridactyla (Linnaeus) , also shorebirds of the genera Arenaria , Gallinago , Limnodromus .

Intermediate hosts. Styloscolex sokolskayae Morev (Lumbriculidae) , Rhyacodrilus coccineus (Vejd) (Tubificidae) , Bryodrilus arcticus and Mesenchytraeus sp. (Mesenchytraeidae) , experimentally ( Bondarenko 1993).

Metacestode. Ramicercus ( Bondarenko 1993).

Localities. Russia (Yakutiya, Chukotka, Kamchatka, the Wrangel Island ), USA (Alaska, state Washington) .

Material studied. Type specimen ( USNPC 47086 , Rissa tridactyla, St. Lawrence Island , Alaska) .

Supplement to the description by Schiller (1951a), based on the type specimen ( Figures 4A– D ). Scolex 200× 90 mm. Suckers 70–80 mm in diameter. Rostellum 90× 60 mm, rostellar sheath 200× 70 mm. Length of hook 21 mm (length of blade 12, length of base with guard 16 mm); width of hook 10 mm. Testis 100× 60 mm, slightly antiporal. Cirrus sac 205– 230× 25–29 mm, crosses median line. Cirrus reaches 151 mm in length, maximum width in proximal part 8 mm. Approximately one-third of cirrus length covered with relatively large sparsely distributed spines. Seminal receptacle oval, 70× 50 mm, vagina tubular, 110 mm long. Mature uterine proglottides absent.

Remarks. Aploparaksis rissae was known for long only from its original description ( Schiller 1951a). Re-examination of the type specimen by Bondarenko (1993) shows that the hermaphroditic proglottis of A. brachyphallos was described and pictured by Schiller as a proglottis of A. rissae . Inaccuracies which have been admitted in the original description of A. rissae did not give any reasons for Spassky (1963), in describing A. filiformis , and Deblock and Rausch (1968), in describing A. daviesi (both species were described from shorebirds), to differentiate them from A. rissae . Bondarenko (1975) first believed that A. daviesi was a synonym of A. filiformis , and later, having investigated type-specimens of both species, came to the conclusion ( Bondarenko 1993) that they are similar to A. rissae . For the morphology of A. rissae , and data about its life-cycle, see Bondarenko (1975, 1993).

Figures

Figure 4. Aploparaksis rissae Schiller, 1951, a type from Rissa tridactyla, Alaska: (A) scolex, (B) hooks, (C) hermaphroditic proglottis, (D) cirrus. Scale bars: 100 mm (A, C), 50 mm, (D) 20 mm (B).