Data from: A large 28S rDNA-based phylogeny confirms the limitations of established morphological characters for classification of proteocephalidean tapeworms (Platyhelminthes, Cestoda)

Proteocephalidean tapeworms form a diverse group of parasites currently known from 315 valid species. Most of the diversity of adult proteocephalideans can be found in freshwater fishes (predominantly catfishes), a large proportion infects reptiles, but only a few infect amphibians, and a single species has been found to parasitize possums. Although they have a cosmopolitan distribution, a large proportion of taxa are exclusively found in South America. We analyzed the largest proteocephalidean cestode molecular dataset to date comprising more than 100 species (30 new), including representatives from 54 genera (80%) and all subfamilies, thus significantly improving upon previous works to develop a molecular phylogeny for the group. The Old World origin of proteocephalideans is confirmed, with their more recent expansion in South America. The earliest diverging lineages are composed of Acanthotaeniinae and Gangesiinae but most of the presently recognized subfamilies (and genera) appear not to be monophyletic; a deep systematic reorganization of the order is thus needed and the present subfamilial system should be abandoned. The main characters on which the classical systematics of the group has been built, such as scolex morphology or relative position of genital organs in relation to the longitudinal musculature, are of limited value, as demonstrated by the very weak support for morphologically-defined subfamilies. However, new characters, such as the pattern of uterus development, relative ovary size, and egg structure have been identified, which may be useful in defining phylogenetically well-supported subgroups. A strongly supported lineage infecting various snakes from a wide geographical distribution was found. Although several improvements over previous works regarding phylogenetic resolution and taxon coverage were achieved in this study, the major polytomy in our tree, composed largely of siluriform parasites from the Neotropics, remained unresolved and possibly reflects a rapid radiation. The genus Spasskyellina Freze, 1965 is resurrected for three species of Monticellia bearing spinitriches on the margins of their suckers.

囊宫绦虫目（Proteocephalidea）绦虫是一类物种多样性丰富的寄生生物，目前已确认有315个有效物种。成虫阶段的囊宫绦虫类多数寄生于淡水鱼类（以鲇形目鱼类为主），大量类群寄生于爬行动物，仅少数类群感染两栖动物，另有1个物种寄生于负鼠体内。尽管该类群的分布具有世界性，但绝大多数类群仅分布于南美洲。

本研究分析了迄今规模最大的囊宫绦虫分子数据集，涵盖超过100个物种（其中30个为新种），包含54个属（占总属数的80%）以及所有亚科的代表类群，较此前相关研究显著推进了该类群分子系统发育的构建工作。

研究证实囊宫绦虫类起源于旧大陆，并在之后逐渐扩散至南美洲。其最早分化的支系由棘带绦虫亚科（Acanthotaeniinae）与恒河绦虫亚科（Gangesiinae）构成，但目前多数已确认的亚科（及属）并非单系群（monophyletic），因此亟需对该目进行系统性的深层重构，并摒弃当前的亚科分类体系。

支撑该类群传统分类学的主要形态特征，诸如头节（scolex）形态、生殖器官（genital organs）相对于纵肌（longitudinal musculature）的位置等，其分类学价值有限——这一点已通过形态定义的亚科所获得的极低支持率得到验证。不过，新的形态特征，如子宫发育模式、卵巢相对大小以及虫卵结构已被发现，这些特征或可用于界定系统发育支持度较高的亚类群。

本研究还发现了一个支持率极高的支系，该支系包含广泛地理分布范围内的多种蛇类寄生绦虫。尽管本研究在系统发育分辨率与分类单元覆盖度上较此前研究均有提升，但研究构建的系统发育树中仍存在一处主要多歧支（polytomy），该支系主要由新热带区的鲇形目寄生绦虫构成，尚未得到解决，这或许反映了一次快速辐射演化（rapid radiation）事件。

1965年由Freze建立的Spasskyellina属被重新恢复，用以容纳3种原本归类于Monticellia属、且吸盘（suckers）边缘带有棘状微毛（spinitriches）的物种。