Turbellarians source details
Diong, S.Y.J.; Ong, R.S.L.; Tong, S.J.W.; Raquib, T.; Ip, A.Y.C.; Huang, D.; Chang, J.J.M. (2025). Flatworms of Singapore: molecular phylogeny of Polycladida (Platyhelminthes: Rhabditophora) and an annotated checklist of Cotylea species. Raffles Bulletin of Zoology. 73: 348-384.
559601
10.26107/RBZ-2025-0025 [view]
urn:lsid:zoobank.org:pub:7AC418B0-6C58-43B4-B53A-02721AB14262 [view]
Diong, S.Y.J.; Ong, R.S.L.; Tong, S.J.W.; Raquib, T.; Ip, A.Y.C.; Huang, D.; Chang, J.J.M.
2025
Flatworms of Singapore: molecular phylogeny of Polycladida (Platyhelminthes: Rhabditophora) and an annotated checklist of Cotylea species
Raffles Bulletin of Zoology
73: 348-384
Publication
Available for editors 
The taxonomy of polyclads has been a subject of contention due to the inconsistent emphases on
different morphological traits. While past molecular phylogenetic analyses have illuminated relationships amongst
suborders and several families, uncertainties persist at the lower taxonomic levels. This study analysed 270
sequences of 28S rRNA from 135 species to gain insights into many of these relationships, particularly at lower
taxonomic levels. The results recovered the monophyly of the suborders Acotylea and Cotylea, and of the cotylean
families Pseudocerotidae and Prosthiostomidae. However, the family Euryleptidae and the genera Pseudobiceros,
Nymphozoon, and Thysanozoon were shown to be non-monophyletic. Euryleptidae was split into two distinct
clades while Pseudobiceros, Nymphozoon, and Thysanozoon have other genera nested within. The analysis
recovered a clade with Thysanozoon and Acanthozoon that was sister to the clade containing Pseudobiceros,
Phrikoceros, and Nymphozoon. The synonymies of Tytthosoceros and Phrikoceros, Pseudobiceros hymanae,
and Pseudobiceros splendidus, as well as Pseudoceros duplicinctus and Pseudoceros prudhoei were rejected; our
results supported their distinction and so they remain separate. New Tytthosoceros combinations were
established from the phylogeny. The diagnosis of Pseudoceros prudhoei was also emended. Importantly, the
study generated 26 novel cotylean sequences, further enriching our understanding of this diverse order.
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Phrikoceros jannetae Gammoudi, Dittmann, Girstmair, Tomancak, Egger & Bulnes, 2025 accepted as Tytthosoceros jannetae (Gammoudi, Dittmann, Girstmair, Tomancak, Egger, & Bulnes, 2024) (source of synonymy)
Phrikoceros mopsus (Marcus, 1952) accepted as Tytthosoceros mopsus (Marcus, 1952) (status source)
Phrikoceros sagamianus (Kato, 1937) accepted as Tytthosoceros sagamianus (Kato, 1937) (source of synonymy)
Pseudobiceros hymanae Newman & Cannon, 1997 (status source)
Pseudobiceros periculosus Newman & Cannon, 1994 (status source)
Pseudoceros depiliktabub Newman & Cannon, 1994 (status source)
Pseudoceros evelinae Marcus, 1950 (status source)
Phrikoceros mopsus (Marcus, 1952) accepted as Tytthosoceros mopsus (Marcus, 1952) (status source)
Phrikoceros sagamianus (Kato, 1937) accepted as Tytthosoceros sagamianus (Kato, 1937) (source of synonymy)
Pseudobiceros hymanae Newman & Cannon, 1997 (status source)
Pseudobiceros periculosus Newman & Cannon, 1994 (status source)
Pseudoceros depiliktabub Newman & Cannon, 1994 (status source)
Pseudoceros evelinae Marcus, 1950 (status source)