Description of a New Species ofUvitellinaWitenberg, 1923 (Cyclocoelidae: Haematotrephinae), from the Black-Winged Stilt,Himantopus himantopus(Charadriiformes: Recurvirostidae) from the Ukraine

Abstract

Five specimens of a new species of Uvitellina Witenberg collected from the air sacs of a black-winged stilt, Himantopus himantopus, collected from the Kherson Region of the Ukraine, were described. Of the 9 species in the genus, Uvitellina himantopi n. sp. differs from all other species in the ratio of the width to the length of eggs (1∶1.8 [1∶1.6–1∶1.9] compared to a low of 1∶2.2 in Uvitellina adephis and a high of 1∶3.6 in Uvitellina teesae). Uvitellina himantopi n. sp. is most similar to Uvitellina iraquensis because, unlike the other 4 species in the genus with a rudimentary oral sucker (Uvitellina indica, Uvitellina kaniharensis, Uvitellina macroisophaga, and U. teesae), these 2 species have an oral sucker that is typically wider than the pharynx (1∶1.0–1∶1.2 oral sucker width/pharynx width compared to 1∶0.8–1∶0.9 in the other 4 species) and a similar cirrus sac length (370–400 long [3–4% of body length] compared to 300–490 [3–5%]). Uvitellina himantopi n. sp. has a larger body than U. iraquensis (12,118–15,100 long compared to 7,750–10,459), wider eggs (105 maximum width compared to 88), and unlike in U. iraquensis, the vitelline fields of U. himantopi n. sp. are attenuated posteriorly at their confluence to form a conspicuous, posteriorly directed point.