Non-Mimic Color Variant of the False Cleanerfish Aspidontus Taeniatus Found in Okinawa, Japan

Galaxea, Journal of Coral Reef Studies 22: 1-2（2020）

Photogallery

Non-mimic color variant of the false cleanerfish Aspidontus taeniatus found in Okinawa, Japan

Hajime SATO*1, 2, Yoichi SAKAI2, and Tetsuo KUWAMURA3

1 School of Applied Biological Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan 2 Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima 739-8528, Japan 3 School of International Liberal Studies, Chukyo University, Nagoya 466-8666, Japan

* Corresponding author: H. Sato E-mail: [email protected]

Communicated by Andrew Baird (Ecology Editor)

Keywords Aspidontus taeniatus, color variant, mimicry, false cleanerfish

The false cleanerfishAspidontus taeniatus Quoy & Gaimard 1834 (Blenniidae), which resembles the bluestreak cleaner wrasse Labroides dimidiatus (Valenciennes 1839) (Labridae) (Fig. 1A), is the best-known example of mimicry among coral reef fishes (Wickler 1968). We found a brownish color variant of A. taeniatus (approximately 6.5 cm in total length; Fig. 1B, C) on the fringing reef of Sesoko Island, Okinawa, Japan (127°52'E, 26°38'N) in July 2019. It was observed swimming together with similar-sized individuals of normal coloration (Fig. 1B, C) on the reef flat at a depth of 1-2 m. The brownish pattern resembles the only congener, Aspidontus dussumieri (Valenciennes 1836) (Fig. 1D), which is neither a cleaner nor a mimic (Kuwamura 1983). Such a color variant of A. taeniatus has not been reported in the Indo-West Pacific, but a similar brownish pattern has been reported in the Marquesas Islands of French Polynesia, suggesting that it mimics the female of Coris hewetti Randall 1999, the Marquesan endemic cleaner wrasse (Delrieu-Trottin et al. 2016). No cleaning fish with such a color pattern exists in

Fig. 1 A A false cleanerfish Aspidontus taeniatus (upper) posing to receive cleaning by a bluestreak cleaner wrasse Labroides dimidiatus. B and C Color variant (lower; the same individual in both pictures) and mimic coloration of A. taeniatus. D Aspidontus dussumieri. All these photographs were taken on a reef of Sesoko Island by Hajime Sato (A to C) and Tetsuo Kuwamura (D) 2 Sato et al.: Non-mimic color variant of the false cleanerfish

Okinawa, so the brownish A. taeniatus does not seem to mimic any cleaner. The brownish A. taeniatus sometimes changed its color to a bluish mimic pattern when moving between feeding sites but returned to the brownish pattern when feeding. The brownish A. taeniatus occasionally bit the caudal fin of non- posing fish such as small damselfish but mainly bit the tentacles of the tubewormSpirobranchus giganteus (Pallas 1766) and the mantles of the boring clam Tridacna crocea Lamarck 1819, behavior similar to that of the mimic-colored individual of A. taeniatus (see Fujisawa et al. 2018). A quantitative comparison of the feeding behavior between the two color patterns will be reported in the future.

Acknowledgements We thank the staff of the Sesoko Station, Tropical Biosphere Research Center at the University of the Ryukyus for supporting our field research. This work was supported by JSPS KAKENHI Grant Number 19K06845 to T. Kuwamura.

References Delrieu-Trottin E, Planes S, Williams JT (2016) When endemic coral-reef fish species serve as models: endemic mimicry patterns in the Marquesas Islands. J Fish Biol 89: 1834-1838 Fujisawa M, Sakai Y, Kuwamura T (2018) Aggressive mimicry of the cleaner wrasse by Aspidontus taeniatus functions mainly for small blennies. Ethology 124: 432-439 Kuwamura T (1983) Reexamination on the aggressive mimicry of the cleaner wrasse Labroides dimidiatus by the blenny Aspidontus taeniatus. J Ethol 1: 22-33 Wickler W (1968) Mimicry in plants and animals. McGrew-Hill, New York