Universidad de Oriente, Biology Geography Department, Ave. Patricio Lumumba s/n, CP 90500, Santiago de Cuba, Cuba. Hasselt University, Centre for Environmental Sciences, Research Group Zoology: Biodiversity and Toxicology, Universitaire Campus Gebouw D, B-3590 Diepenbeek, Belgium.
Zootaxa. 2021 Mar 23;4948(4):zootaxa.4948.4.1. doi: 10.11646/zootaxa.4948.4.1.
The taxon Koinocystididae is the third most species-rich family within Eukalyptorhynchia. However, its diversity and phylogeny have been largely neglected in former studies. We introduce three new genera and twelve new species of Koinocystididae including Simplexcystis asymmetrica gen. n. sp. n., Galapagetula cubensis sp. n., eight species of Reinhardorhynchus gen. n. and two species of Itaipusa. This raises the total number of species within Koinocystididae from 51 to 63. We also report on new distribution records for six known species: I. divae (Cuba, Panama and New Caledonia), I. karlingi (Sardinia and Lanzarote), Reinhardorhynchus riegeri comb. n. (Cuba), R. ruffinjonesi comb. n. (Cuba and Panama), Utelga heinckei (Cuba and Lanzarote), and U. pseudoheinckei (Sardinia). Simplexcystis asymmetrica gen. n. sp. n. is characterised by a male duct running eccentrically through the copulatory bulb, lack of any hard structures in the male system, lack of a bursa, and the fact that the epithelia of the female, the male, and part of the common atrium are covered by a brush border. Galapagetula cubensis sp. n. has a caudal gonopore, a divisa-type copulatory bulb with an unarmed penis papilla, and a female duct without a sphincter. The new species of Itaipusa and Reinhardorhynchus gen. n. differ from their congeners in the detailed structure of the copulatory bulb and especially the hard structures associated with it. In a molecular phylogenetic analysis based on all available 18S and 28S rDNA sequences of koinocystidids, we found support for the monophyly of the family and the genus Utelga Marcus, 1949. The genus Itaipusa is not monophyletic in that I. sinensis forms a clade with Rhinolasius dillonicus, while other species of Itaipusa that have a copulatory bulb armed with hooks form a clade together with Sekerana stolzi. As the type species of Itaipusa (I. divae) is in neither of these clades, we erected a new genus for I. sinensis (Koinogladius gen. n.) and one for species of Itaipusa having a hook-bearing copulatory bulb (Reinhardorhynchus gen. n.), respectively. Whether the remaining species of Itaipusa form a monophylum remains uncertain.
科伊诺克西蒂斯科是真旋壳目第三大物种丰富的科。然而，在以前的研究中，它的多样性和系统发育很大程度上被忽视了。我们介绍了三个新的科伊诺克西蒂斯科的属和十二个新种，包括 Simplexcystis asymmetrica 新属新种、Galapagetula cubensis 新种、 Reinhardorhynchus 属的八种新种和 Itaipusa 的两种新种。这使得科伊诺克西蒂斯科的物种总数从 51 种增加到 63 种。我们还报告了六个已知物种的新分布记录：I. divae（古巴、巴拿马和新喀里多尼亚）、I. karlingi（撒丁岛和兰萨罗特岛）、Reinhardorhynchus riegeri 组合。n.（古巴）、R. ruffinjonesi 组合。n.（古巴和巴拿马）、Utelga heinckei（古巴和兰萨罗特岛）和 U. pseudoheinckei（撒丁岛）。Simplexcystis asymmetrica 新属新种的特征是雄性导管偏心穿过交配球，雄性系统中没有任何硬结构，没有囊，雌性、雄性和部分共同心房的上皮被刷状边界覆盖。Galapagetula cubensis 新种有一个尾肛孔，一种具有无武装阴茎乳突的 divisa 型交配球，以及一个没有括约肌的雌性导管。新种的 Itaipusa 和 Reinhardorhynchus 属与它们的同属种在交配球的详细结构，特别是与之相关的硬结构上有所不同。在基于所有可用的真旋壳目 18S 和 28S rDNA 序列的分子系统发育分析中，我们发现该科和属 Utelga Marcus, 1949 的单系性得到了支持。Itaipusa 属并非单系，因为 I. sinensis 与 Rhinolasius dillonicus 形成一个分支，而具有带钩交配球的其他 Itaipusa 种则与 Sekerana stolzi 形成一个分支。由于 Itaipusa 的模式种（I. divae）不在这两个分支中，我们分别为 I. sinensis（Koinogladius 属）和具有带钩交配球的 Itaipusa 种（Reinhardorhynchus 属）建立了一个新属。Itaipusa 的其余种是否形成一个单系仍然不确定。
