Rothman Gregory K, Hill-Spanik Kristina M, Wagner Graham A, Kendrick Michael R, Kingsley-Smith Peter R, de Buron Isaure
Marine Resources Research Institute, South Carolina Department of Natural Resources, Charleston, SC, 29412, USA.
Department of Biology, College of Charleston, Charleston, SC, 29412, USA.
Syst Parasitol. 2024 Dec 9;102(1):11. doi: 10.1007/s11230-024-10195-8.
A new genus and species within the family Polymorphidae Meyer, 1931 were erected to accommodate cystacanths recovered from the mesentery of individuals from a non-native population of the red swamp crayfish Procambarus clarkii (Girard), collected from South Carolina (USA). Morphological characteristics of the specimens collected included in both sexes a spindle-shaped body with a slender hindtrunk, two fields of markedly different sized spines on the foretrunk, the presence of a middle row of smaller scythe-shaped hooks on a proboscis armed with 19-20 longitudinal rows of 14-16 hooks; and in males, six cement glands, absence of genital spines, and a digitiform and spinose bursa (observed inverted). Sequencing portions of both the mitochondrial cytochrome c oxidase I (COI) and large subunit ribosomal RNA genes was completed, followed by phylogenetic analysis of a concatenated alignment. Sequences from our specimens appeared in a clade with those of Hexaglandula corynosoma (Travassos, 1915) and Ibirhynchus dimorpha (Schmidt, 1973) but were 27% divergent from both using the COI marker. The genetic divergence of this parasite from other polymorphid genera, along with unique morphological features, justified erecting a new genus and new species. Herein we describe Heterospinus mccordi n. gen. n. sp. bringing the total number of genera within the family Polymorphidae to 16, and we emend and update the latest key that was provided for the genera within this family. This is the first record of polymorphids infecting P. clarkii outside of its native range. The definitive host remains unknown.
1931年，Meyer建立了多形科（Polymorphidae），其中一个新属和新物种被建立，用于容纳从美国南卡罗来纳州采集的非本地种群克氏原螯虾（Procambarus clarkii (Girard)）个体肠系膜中回收的囊棘。所收集标本的形态特征包括：两性均具有纺锤形身体和细长的后躯干；前躯干上有两个明显不同大小棘刺的区域；在有19 - 20排纵向排列、每排14 - 16个钩的吻上，有一排中间较小的镰刀形钩；雄性有六个粘腺，无生殖刺，有指状且具刺的囊（观察到为倒置状态）。完成了线粒体细胞色素c氧化酶I（COI）和核糖体RNA大亚基基因部分的测序，随后对串联比对进行系统发育分析。我们标本的序列与六腺科（Hexaglandula corynosoma (Travassos, 1915)）和双形科（Ibirhynchus dimorpha (Schmidt, 1973)）的序列出现在一个分支中，但使用COI标记时与两者的差异均为27%。这种寄生虫与其他多形科属的遗传差异以及独特的形态特征，证明有必要建立一个新属和新物种。在此，我们描述了麦氏异棘属（Heterospinus mccordi）新属新种，使多形科内的属总数达到16个，并且我们修订和更新了该科内属的最新检索表。这是多形科寄生虫在克氏原螯虾原生范围之外感染该物种的首次记录。终末宿主仍然未知。
