Onset of Autotomy in an Attached Cycloseris Coral

Galaxea, Journal of Coral Reef Studies 14: 25-26（2012）

Photogallery

Onset of autotomy in an attached Cycloseris coral

Bert W. HOEKSEMA1, * and Zarinah WAHEED1, 2

1 Department of Marine Zoology, Naturalis Biodiversity Centre, P.O. Box 9517, 2300 RA Leiden, The Netherlands 2 Borneo Marine Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia

* Corresponding author: B.W. Hoeksema E-mail: [email protected]

Communicated by Hiroya Yamano (Editor-in-Chief)

Keywords Fragmentation, Free-living, Fungiidae, Mushroom corals

Free-living mushroom corals of the genus Cycloseris (Scleractinia: Fungiidae) are either complete individuals or fragments in various stages of fission and regeneration (Hoeksema and Waheed 2011). Their fragmentation is initiated by a process of radial skeleton dissolution called autotomy (Yamashiro et al. 1989; Yamashiro and Nishihira 1994). Only unattached fragmenting corals are known, representing the adult anthocyathus stage. The anthocaulus stage in which juveniles of free-living species are still attached, as in Fungia fungites (Linnaeus, 1758) (see Hoeksema and Yeemin 2011), has not been reported for fragmenting Cycloseris corals before (see e.g. Colley et al. 2002). During a biodiversity survey on the coral reefs of Kota Kinabalu, Malaysia (5°57′-6°5′N, 115°59′-116°5′E) from 16 to 28 July 2011, a small specimen of Cycloseris sinensis (Milne Edwards and Haime, 1851) still attached to hard substrate was found at 16 m depth on the lower reef slope of Manukan I. At first sight it did not appear attached (Fig. 1a) but when it was held for further examination, it became separated from a stalk. Aside from a fresh detachment wound (Fig. 1b, c) there were grooves along radial lines on its underside as early signs of autotomy (Fig. 1b). This specimen represents the first record of self-fragmentation in attached Cycloseris corals.

Fig. 1 Anthocaulus stage of Cyloseris sinsensis at Kota Kinabalu, Malaysia. a Upper surface of attached coral. b Underside of the same coral showing detachment wound and onset of radial fragmentation lines (arrows). c Close-up of wound. Scale bars a, b: 0.5 cm, c: 0.2 cm 26 Hoeksema and Waheed: Onset of autotomy in an attached Cycloseris coral

Acknowledgments Research permission was granted by Sabah Parks and the Economic Planning Unit, Malaysia. We thank Prof. Dr. Ridzwan Abdul Rahman of the Borneo Marine Research Institute, and the boat house crew of Universiti Malaysia Sabah for support during the fieldwork.

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