Marzoug Douniazed, Rima Mohamed, Boutiba Zitouni, Georgieva Simona, Kostadinova Aneta, Pérez-del-Olmo Ana
Laboratoire Réseau de Surveillance Environnementale, Département de Biologie, Université d'Oran, 31000, Oran, Algeria.
Syst Parasitol. 2014 Feb;87(2):127-34. doi: 10.1007/s11230-013-9468-x. Epub 2014 Jan 29.
A new hemiurid digenean, Saturnius gibsoni n. sp., is described from the stomach lining of Mugil cephalus L. off Oran, Mediterranean coast of Algeria. Characteristic morphological features of the new species include small size of the body which is comprised of six pseudosegments, small ventral sucker, weakly developed mound-shaped flange at the level of the ventral sucker, and eggs being large in relation to the size of the body. Saturnius gibsoni n. sp. resembles S. minutus Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006 and two unidentified Saturnius spp. in the small size of the body and most metrical features. However, in spite of the presence of five transverse septa resulting in six pseudosegments and the range overlap of some metrical features, the ventral sucker in S. minutus is much larger, the ventral sucker muscular flange is more prominent, the last pseudosegment is narrower in relation to body width and more rounded, and the eggs are smaller (mean 21 × 10 vs 25 × 12 μm). Furthermore, the partial sequences of the 28S rRNA gene region (domains D1-D3; 1,195 nt) obtained from two isolates of S. gibsoni n. sp. differed by 11 nt (0.9%) from that of S. minutus. Both unidentified forms of Saturnius are clearly distinguishable from S. gibsoni n. sp. by the presence of six stout, transverse muscular septa, forming seven pseudosegments (vs five septa forming six pseudosegments). Bayesian inference analysis of partial 28S rDNA sequences based on a total of 15 species from the families Hemiuridae and Lecithasteridae depicted the Bunocotylinae Dollfus, 1950 as a strongly supported basal clade, with Bunocotyle progenetica (Markowski, 1936) as the closest sister taxon to Saturnius spp.
一种新的半尾科复殖吸虫——吉氏土星吸虫（Saturnius gibsoni n. sp.），是从阿尔及利亚地中海沿岸奥兰附近的鲻鱼（Mugil cephalus L.）胃黏膜中发现并描述的。新物种的特征形态学特征包括：体型小，由六个假节组成；腹吸盘小；腹吸盘水平处的丘状边缘发育较弱；相对于体型而言，虫卵较大。吉氏土星吸虫（Saturnius gibsoni n. sp.）在体型小以及大多数测量特征方面与微小土星吸虫（S. minutus Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006）和两种未鉴定的土星吸虫属物种相似。然而，尽管存在五个横向隔膜导致六个假节，且一些测量特征范围重叠，但微小土星吸虫的腹吸盘要大得多，腹吸盘的肌肉边缘更突出，最后一个假节相对于体宽更窄且更圆，并且虫卵更小（平均21×10 微米对25×12 微米）。此外，从吉氏土星吸虫（Saturnius gibsoni n. sp.）的两个分离株获得的28S rRNA基因区域（结构域D1 - D3；1195个核苷酸）的部分序列与微小土星吸虫的序列相差11个核苷酸（0.9%）。两种未鉴定的土星吸虫属物种与吉氏土星吸虫（Saturnius gibsoni n. sp.）明显不同，前者有六个粗壮的横向肌肉隔膜，形成七个假节（而五个隔膜形成六个假节）。基于半尾科和列氏吸虫科共15个物种的28S rDNA序列的贝叶斯推断分析表明，1950年的布氏吸虫亚科（Bunocotylinae Dollfus）是一个得到有力支持的基部类群，其中布氏原吸虫（Bunocotyle progenetica (Markowski, 1936)）是土星吸虫属物种最亲近的姐妹分类单元。
