Kostadinova Aneta, Skirnisson Karl
Central Laboratory of General Ecology, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
Syst Parasitol. 2007 Nov;68(3):217-23. doi: 10.1007/s11230-007-9092-8. Epub 2007 Sep 25.
Petasiger islandicus n. sp. is described and figured from a demographically isolated population of the horned grebe Podiceps auritus auritus (L.) in Lake Mývatn (Iceland). This new species belongs to the group of species with 19 collar spines which possess a large elongate-oval cirrus-sac, well-developed pars prostatica and massive bulb-like cirrus. Within this group, P. islandicus appears most similar to P. oschmarini Kostadinova & Gibson, 1998, a form with similar body dimensions described from the same host, but differs in having a larger head collar, collar spines, oral sucker, pharynx, testes and sucker-width ratio, and a smaller cirrus-sac, cirrus and eggs. Two Nearctic species resemble P. islandicus in general morphology but differ as follows: P. pseudoneocomense Bravo-Hollis, 1969 has a larger body and collar width, notably shorter collar spines, smaller testes and sucker-width ratio, and a shorter but much wider cirrus-sac which is also smaller relative to the ventral sucker and almost entirely anterior to it; and P. caribbensis Nassi, 1980 has a smaller body, shorter collar spines and a seminal vesicle which is small in relation to the cirrus-sac, vitelline fields reaching anteriorly to the level of the genital pore and the intestinal bifurcation is located more anteriorly.
冰岛新种冰岛佩塔吸虫（Petasiger islandicus n. sp.）是根据冰岛米湖（Lake Mývatn）中角䴙䴘（Podiceps auritus auritus (L.)）一个种群数量孤立的群体进行描述和绘图的。这个新物种属于具有19根颈棘的物种群，该物种群具有大的长椭圆形的阴茎囊、发育良好的前列腺部和巨大的球状阴茎。在这个群体中，冰岛佩塔吸虫看起来与1998年科斯塔迪诺娃和吉布森描述的奥氏佩塔吸虫（P. oschmarini）最为相似，后者来自同一宿主，身体尺寸相似，但冰岛佩塔吸虫的头冠、颈棘、口吸盘、咽、睾丸与吸盘宽度比更大，而阴茎囊、阴茎和虫卵更小。两种新北区物种在总体形态上与冰岛佩塔吸虫相似，但有以下不同：1969年的拟新康吸虫（P. pseudoneocomense Bravo-Hollis）身体和头冠宽度更大，颈棘明显更短，睾丸和吸盘宽度比更小，阴茎囊更短但宽得多，相对于腹吸盘也更小，且几乎完全位于其前方；1980年的加勒比佩塔吸虫（P. caribbensis Nassi）身体更小，颈棘更短，精囊相对于阴茎囊较小，卵黄腺向前延伸到生殖孔水平，肠分支位于更前方。
