WoRMS source details
Hasegawa, N.; Kajihara, H. (2019). A redescription of Syncarpa composita (Ascidiacea, Stolidobranchia) with an inference of its phylogenetic position within Styelidae. ZooKeys. 857: 1-15.
353761
10.3897/zookeys.857.32654 [view]
Hasegawa, N.; Kajihara, H.
2019
A redescription of Syncarpa composita (Ascidiacea, Stolidobranchia) with an inference of its phylogenetic position within Styelidae
ZooKeys
857: 1-15
Publication
Available for editors [request]
Two species of styelid colonial ascidians in the genus Syncarpa Redikorzev, 1913 are known from the
northwest Pacific. The valid status of the lesser known species, Syncarpa composita (Tokioka, 1951) (type
locality: Akkeshi, Japan), is assessed here. To assess the taxonomic identity of S. composita, we compared one of the syntypes and freshly collected topotypes of S. composita with a syntype of S. oviformis
Redikorzev, 1913 (type locality: Ul’banskij Bay, Russia). Specimens of S. composita consistently differed
from the syntype of S. oviformis in the number of oral tentacles, the number of size-classes of transverse
vessels, and the number of anal lobes. In this paper, S. composita is redescribed as distinct from S. oviformis,
and its phylogenetic position inferred within Styelidae based on the 18S rRNA and cytochrome c oxidase
subunit I gene sequences. In our phylogenetic tree, Syncarpa formed a well-supported clade together with
Dendrodoa MacLeay, 1824. In Syncarpa and Dendrodoa, a single gonad is situated on the right side of the
body, which is unique among Styelidae, and thus can be a synapomorphy for this clade.
Japan
Systematics, Taxonomy
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Syncarpa composita (Tokioka, 1951) (additional source)