Polystoma from

Key to species of Polystoma from View in CoL Ukraine

1. In Pelobatidae View in CoL ......................................................................................................................................................2

— In other hosts........................................................................................................................................................3

2. Hamuli underdeveloped. Hamuli present as primordia with length of 15 μm, situated between FIrst pair of suckers and slightly anteriorly to marginal hooklets. Body length 6.574 ( 5.405 –8.378) mm, body width 2.285 ( 1.703 –2.756) mm. Near Lake Durankulak ( Bulgaria). Parasite of common spadefoot, Pelobates fuscus View in CoL ...................................................................................... P. fuscus Biserkov & Hadjinikolova, 1993 View in CoL

— Hamuli developed................................................................................................................................................3

3. In Hylidae View in CoL . Body length 3.4 ( 2.964 –4.275) mm, body width 1.4 ( 1.235 –1.651) mm. Hamuli (average): a 217, b 199, c 64, d 60 μm; ratio a/b 1.1, b/c 3.1, b/d 3.3. Parasite of common tree frog, Hyla arborea, Petrich ( Bulgaria) View in CoL . ............................................................................................... P. skrjabini Buchvarov, 1984 View in CoL

— In other hosts........................................................................................................................................................4

4. In Bufonidae View in CoL . Body length 9.8 (8.9-10.8) mm. Hamuli (average): a 418, b 338, c 93, d 51μm; ratio a/b 1.1, b/c4.2, b/d 7.9. In Corsica ( France), Plovdiv ( Bulgaria), Kyiv, Kherson Region, Crimea ( Ukraine); parasite of green toad, Bufotes viridis View in CoL ...................................... P. viridis Euzet, Combes, Batchvarov, 1974 View in CoL

— In Ranidae View in CoL ..............................................................................................................................................................5

5. Ratio of hamuli measurements a/b about 2.0. Ratios b/c 0.7, b/d 0.8. Slots between spines on basal end of the crown deep. Average body length 10.1, body width 3.4 mm. Hamuli (average): a 480, b 233, c 359, d 298 μm. Parasite of common frog, Rana temporaria View in CoL , wide spread throughout the distribution area of the host........................................................................................................... P. integerrimum (Fröhlich, 1798) View in CoL

— Ratio of hamuli measurements a/b much smaller than 2.0...........................................................................6

6. Slots between spines on basal end of the crown deep. A constriction part in the crown of the spines of copulatory organ is situated at 1/3 of the length of the spines, close to their dorsal ends. Ratio of hamuli measurements: a/b 1.5, b/c 0.9, b/d 2. In Western Poland and Lviv Region ( Ukraine). Parasite of moor frog, Rana arvalis View in CoL ............................................................................................ P. scuratovitchi Buchvarov 1984

— Slots between spines on basal end of the crown spines of copulatory organ shallow. A constriction part in the crown of the spines of copulatory organ situated at 1/5 of the length of the spines, close to their dorsal ends. In Plovdiv, Razlog, Jahoruda and Guljna bania ( Bulgaria); Yalova Province, Çinarcik County ( Turkey); Lviv Region ( Ukraine). Parasite of agile frog, Rana dalmatina View in CoL ...................................... .......................................................................................................................... P. mazurmovici Buchvarov 1980 View in CoL