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The Rhoptrobothriidae are one of the more enigmatic families of cestodes of elasmobranchs. Opinions on the taxonomic status of the family’s three original genera (i.e., Myzophyllobothrium, Rhoptrobothrium, and Myzocephalus) have varied over the 115 years since they were erected. Some authors have considered all three valid, others have considered Rhoptrobothrium to be a synonym of Myzopyllobothrium or a genus inquirendum, yet others have considered Myzocephalus to be a synonym of the phyllobothriid genus Thysanocephalum. All three genera were established for specimens collected from eagle rays off Sri Lanka. The erection of Mixophyllobothrium for two specimens from a cowtail stingray off India three decades ago added additional confusion to the situation, with some authors considering it valid and others a synonym of Myzocephalus. These disagreements stem largely from differences in interpretation of the complex morphology of the scolex of members of these genera. Furthermore, with the exception of Rhoptrobothrium comprising four species, each genus is monotypic. All but Rhoptrobothrium has not been considered in detail for nearly a century, largely because of a lack of available material. The taxonomic status of these genera is assessed here based on light and scanning electron microscopy, and molecular data generated from new material collected from eagle rays off Indonesian and Malaysian Borneo, Japan, Sri Lanka, and Viet Nam. Morphological work indicates that the genera differ largely only in the degree of folding of the four remi that extend from the cephalic peduncle. A molecular phylogeny based on sequence data for the D1–D3 region of the 28S rRNA gene, which include new data for eight specimens of four species, indicates that Myzophyllobothrium, Myzocephalus, and Rhoptrobothrium are not mutually monophyletic. The latter two genera and Mixophyllobothrium are considered synonyms of Myzophyllobothrium and five species are transferred to that genus. Myzophyllobothrium okamuri n. comb. is considered a species inquirendum. Myzophyllobothrium nagasawai n. sp. is described from Aetobatus narutobiei off Japan. Myzophyllobothrium narinari n. comb. is re-described based on newly collected cestodes from the type host and locality (i.e., Aetobatus ocellatus off Sri Lanka). Despite consisting of only a single genus, the family status of the group is retained in recognition of the unusual configuration of the scolex, which bears four biloculate bothridia and four remi extending from the cephalic peduncle. The ordinal placement of the family remains uncertain, but affinities with the Phyllobothriidea, rather than “Tetraphyllidea” are considered.
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A compendium of generic names of agarics and Agaricales
Abstract Agarics (gilled mushrooms) and the order Agaricales include some of the best‐known and most charismatic fungi. However, neither group has had its constituent genera exhaustively compiled in a modern phylogenetic context. To provide that framework, we identified and analyzed 1383 names of genera of agarics (regardless of taxonomic placement) and the Agaricales (regardless of morphology), compiling various data for each name. Including 590 accepted names, the other 793 listed with reasons explaining their disuse, this compendium is intended to be comprehensive at present and phylogenetically up‐to‐date. Data we gathered included type species, continents from which type species were described, accepted synonyms of those species, current family placements, gross macromorphological categories, and sequenced loci (for type specimens, type species, and each genus as a whole). Index Fungorum provided a basis for the data, but much was manually confirmed, augmented, or corrected based on recent literature. Among accepted gilled genera, 82% belonged to the Agaricales; among accepted genera of Agaricales, 67% were gilled. Based on automated searches of GenBank and MycoCosm, 7% of generic names had DNA sequences of their type specimens, 68% had sequences of their type species, and 87% had sequences representing their genus. This leaves an estimated 103 accepted genera entirely lacking molecular data. Some subsets of genera have been sequenced relatively thoroughly (e.g., nidularioid genera and genera described from Europe); others relatively poorly (e.g., cyphelloid genera and genera described from Africa and tropical Asia). We also list nomenclaturally threatened and taxonomically doubtful genus and family names.
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- Award ID(s):
- 2030779
- PAR ID:
- 10633796
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- TAXON
- Volume:
- 69
- Issue:
- 3
- ISSN:
- 0040-0262
- Page Range / eLocation ID:
- 425 to 447
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/tax.12240
