Scholz Tomáš, Choudhury Anindo, Brooks Daniel R
1 Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic.
2 Division of Natural Sciences, St. Norbert College, 100 Grant Street, De Pere, Wisconsin 54115.
J Parasitol. 2019 Feb;105(1):79-84.
A new species of the recently erected genus of proteocephalid cestodes, Synbranchiella Arredondo, Alves and Gil de Pertierra, 2017 , is described based on specimens found in the mountain mullet, Dajaus monticola (Bancroft, 1834), from Costa Rica. The new species is placed in Synbranchiella because of the cortical position of the genital organs (typical of the former subfamily Monticelliinae); a robust scolex (lacking a metascolex) having a dome-shaped apex and biloculate suckers (lacking free posterior margins); vitelline follicles in 2 narrow lateral bands; a vagina always anterior to the cirrus-sac; and a genital pore that is markedly pre-equatorial, i.e., close to the anterior margin of proglottids. The new species, Synbranchiella megacirrus, differs from the type and only other species of the genus, Synbranchiella mabelae Arredondo, Alves and Gil de Pertierra, 2017 , that infects the marbled swamp eel, Synbranchus marmoratus Bloch, 1795, in Argentina by the absence of preporal vitelline follicles (present in S. mabelae); a well-developed, large, elongate vaginal sphincter (small and ring-like in S. mabelae); and a large cirrus-sac relative to the proglottid size (cirrus-sac length is on average 48% of the proglottid width in S. megacirrus vs. 31% in the latter species). This is the first adult tapeworm reported from mountain mullet and the first record of the genus outside of South America, thereby greatly extending the range of distribution of species of Synbranchiella.
基于在来自哥斯达黎加的山鲻（Dajaus monticola，Bancroft，1834）体内发现的标本，描述了绦虫纲 Proteocephalidae 科中最近建立的 Synbranchiella 属的一个新物种。该新物种被归入 Synbranchiella 属，原因如下：生殖器官位于皮层（这是前 Monticelliinae 亚科的典型特征）；具有强健的头节（无后原头节），顶端呈圆顶形，吸盘分两叶（无游离后缘）；卵黄滤泡位于两条狭窄的侧带；阴道总是位于阴茎囊前方；生殖孔明显位于赤道前方，即靠近节片前缘。新物种 Synbranchiella megacirrus 与该属的模式种及唯一的另一个物种，即感染阿根廷的云斑尖塘鳢（Synbranchus marmoratus Bloch，1795）的 Synbranchiella mabelae Arredondo、Alves 和 Gil de Pertierra，2017 不同之处在于：无前侧卵黄滤泡（S. mabelae 有）；阴道括约肌发达、大且细长（S. mabelae 小且呈环状）；相对于节片大小，阴茎囊大（S. megacirrus 中阴茎囊长度平均为节片宽度的48%，而后者为31%）。这是首次报道山鲻体内的成虫绦虫，也是该属在南美洲以外地区的首次记录，从而极大地扩展了 Synbranchiella 属物种的分布范围。
