Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, 370 05 České Budějovice, Czech Republic.
Department of Invertebrates, Natural History Museum, P.O. Box 6434, CH-1211 Geneva 6, Switzerland.
Parasitol Int. 2024 Oct;102:102916. doi: 10.1016/j.parint.2024.102916. Epub 2024 Jun 25.
A new genus, Cordicestus, is proposed to accommodate proteocephalid tapeworms parasitising gars (Lepisosteiformes: Lepisosteidae) in North and Central America that were previously placed in the polyphyletic genus Proteocephalus Weinland, 1858. The new genus differs from other proteocephalid genera by the particular morphology of the scolex, which is small, protrudes apically but has no apical organ, and bears flat, heart-shaped (= cordis) suckers. In addition, the species of the new genus have an elongated cirrus sac with an almost straight internal vas deferens and wide, sinuous ventral osmoregulatory canals with secondary canals directed outwards. The type species of the new genus, Cordicestus singularis (La Rue, 1911) n. comb., is redescribed based on new material from the shortnose gar, Lepisosteus platostomus Rafinesque (type host), and the spotted gar, L. oculatus Winchell, in the United States. Cordicestus rafaeli n. sp. is described from the tropical gar, Atractosteus tropicus Gill, in Mexico. The new species differs from its relatives primarily by the presence of craspedote proglottids (acraspedote in other species) and some biometric features. All species of Cordicestus are revised, including unidentified specimens from A. tropicus and the Cuban gar A. tristoechus (Bloch and Schneider) in Nicaragua and Cuba, respectively, which may be new species, and a key to the identification of these taxa is provided. Molecular data available for two nominal species of the new genus indicate the possible existence of another species of Cordicestus in Lepisosteus in the USA.
提出了一个新属，Cordicestus，以容纳寄生在北美的北美和中美洲的雀鳝（硬骨鱼纲：雀鳝科）中的多歧绦虫，这些寄生虫以前被归入多歧绦虫属 Proteocephalus Weinland，1858。新属与其他多歧绦虫属的区别在于头节的特殊形态，头节小，突出于顶端，但没有顶端器官，并且具有扁平的心形 (=cordis)吸盘。此外，该新属的物种具有细长的环子宫囊，其内输精管几乎笔直，宽阔的、蜿蜒的、具有次级通道的腹侧渗透调节管向外定向。新属的模式种，Cordicestus singularis (La Rue, 1911) n. comb.，是根据来自短吻雀鳝，Lepisosteus platostomus Rafinesque（模式宿主）和斑点雀鳝，L. oculatus Winchell 的新材料重新描述的，这两种鱼都来自美国。Cordicestus rafaeli n. sp. 是从墨西哥的热带雀鳝，Atractosteus tropicus Gill 描述的。新种与它的近亲主要区别在于存在卷曲的孕节（其他种为无卷曲的孕节）和一些生物测量特征。对所有 Cordicestus 物种进行了修订，包括来自 A. tropicus 和古巴雀鳝 A. tristoechus（Bloch 和 Schneider）的未鉴定标本，这些标本可能是新种，并提供了这些分类单元的鉴定钥匙。为两个新属的两个命名种提供的分子数据表明，在美国的 Lepisosteus 中可能存在另一种 Cordicestus 物种。
