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Abstract BackgroundThe Red Sea contains thousands of kilometers of fringing reef systems inhabited by clownfish and sea anemones, yet there is no consensus regarding the diversity of host anemone species that inhabit this region. We sought to clarify a historical record and recent literature sources that disagree on the diversity of host anemone species in the Red Sea, which contains one endemic anemonefish,Amphiprion bicinctusRüppell 1830. ResultsWe conducted 73 surveys spanning ~ 1600 km of coastline from the northern Saudi Arabian Red Sea to the Gulf of Aden and encountered seven species of host anemones, six of which hostedA. bicinctus.We revise the list of symbionts forA. bicinctusto includeStichodactyla haddoni(Saville-Kent, 1893) andStichodactyla mertensiiBrandt, 1835 which were both observed in multiple regions. We describe Red Sea phenotypic variability inHeteractis crispa(Hemprich & Ehrenberg in Ehrenberg, 1834) andHeteractis aurora(Quoy & Gaimard, 1833), which may indicate that these species hybridize in this region. We did not encounterStichodactyla gigantea(Forsskål, 1775), although the Red Sea is the type locality for this species. Further, a thorough review of peer-reviewed literature, occurrence records, and misidentified basis of record reports dating back to the early twentieth century indicate that it is unlikely thatS. giganteaoccurs in the Red Sea. ConclusionsIn sum, we present a new guide for the host anemones of the Red Sea, revise the host specificity ofA. bicinctus,and question whetherS. giganteaoccurs in the central and western Indian Ocean.
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Novel in situ observations of asexual reproduction in the carpet sea anemone, Stichodactyla mertensii (Stichodactylidae, Actiniaria)
Merten’s carpet sea anemone, Stichodactyla mertensii Brandt, 1835, is the largest known sea anemone species in the world, regularly exceeding one meter in oral disc diameter. A tropical species from the Indo-Pacific, S. mertensii drapes prominently over coral reef substrates and is a common host to numerous species of clownfishes and other symbionts throughout its range, which extends from the Red Sea through the Central Pacific Ocean. Long thought to reproduce via sexual reproduction only, recent genetic evidence suggests it may rarely reproduce asexually as well, although this process had never been confirmed through direct observation and the mechanism was yet to be described. Here, we directly observed and documented in situ asexual fragmentation via budding, in real time, by a Red Sea S. mertensii in a turbid inshore reef environment. While asexual reproduction is not unusual in sea anemones as a group, it is typically expected to be uncommon for large-bodied species. Herein, we describe S. mertensii fragmentation, provide high resolution images of the event from the Saudi Arabian coastline at multiple time points, and confirm asexual reproduction for this species.
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- Award ID(s):
- 2205567
- PAR ID:
- 10395911
- Date Published:
- Journal Name:
- ZooKeys
- Volume:
- 1103
- ISSN:
- 1313-2989
- Page Range / eLocation ID:
- 57 to 63
- 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/10.3897/zookeys.1103.84415
