The Redhead Goby, Paragobiodon echinocephalus, is a small fish with a black body and fins and a large red-orange head that is covered in soft, short bristles. It is found in coral reefs from the Red Sea and Madagascar in the West to Polynesia and Australia in the East (Herre 1936). This goby inhabits live coral heads of scleractinian corals, in particular, the hood coral, Stylophora pistillata (Kuwamura et al. 1994a, Belmaker et al. 2007) and the cauliflower coral, Pocillopora damicornis (Lassig 1977). The fishes rely on their coral host for food, shelter from predation, and breeding sites.
Redhead gobies may live in a coral singly, in pairs, or in groups, with larger coral generally hosting larger groups of fishes. Within an individual coral, only the largest two fish will breed (Kuwamura et al. 1993). After the female spawns on the coral, the father will guard the eggs until they hatch (Kuwamura et al. 1993).
Like many reef fishes, redhead gobies are capabable of changing sex (sequential hermaphroditism). But unlike most sequential hermaphrodites who change sex only once during their lifetime, P. echinocephalus may change sex repeatedly in either direction (Nakashima et al. 1995). In fact, the phenomenon of multiple changes from female to male or male to female (serial hermaphroditism) was first described in this species (Kuwamura et al. 1994b).
- Belmaker, J., O. Polak, N. Shashar, Y. Ziv. 2007. Geographic divergence in the relationship between Paragobiodon echinocephalus and its obligate coral host. Journal of Fish Biology 71(5):1555–1561.
- Herre, A. W. 1936. Fishes of the Crane Pacific Expedition. Field Museum of Natural History Zoological series, v. 21, Chicago. http://dx.doi.org/10.5962/bhl.title.2729
- Kuwamura, T. Yogo, Y., Nakashima, Y. 1993. Size-assortative monogamy and paternal egg care in a coral goby Paragobiodon echinocephalus. Ethology. 95:65–75.
- Kuwamura, T. Yogo, Y., Nakashima, Y. 1994a. Population dynamics of goby Paragobiodon echinocephalus and host coral Stylophora pistillata. Marine Ecology Progress Series 103:17-23.
- Kuwamura, T. Yogo, Y., Nakashima, Y. 1994b. Sex change in either direction by growth rate advantage
- in a monogamous coral goby Paragobiodon echinocephalus . Behav. Ecol. 5: 434–438.
- Lassig, B. R. 1997. Communication and coexistence in a coral community. Marine Biology 42:85-92.
- Nakashima, Y., Kuwamura, T., Yogo, Y. 1995. Why be a both-ways sex changer. Ethology 101: 301-307.