標題: [河溪 Stream] [Overseas] Sicyopterus largocephalus in Iriomote Jun 2017 [打印本頁] 作者:
jasonpoon 時間: 2017-8-17 00:41 標題: [Overseas] Sicyopterus largocephalus in Iriomote Jun 2017
One of the earliest described and most studied sicydiins. Watched many individuals (sizes circa 2-8cm) in lower reach of clear fast flowing stream with large boulders and rocky bottom. Water should be fresh and low salt content although its reaching the beach and mangrove soon. Isolated stepwise rock pools and rapids. Male in breeding color typically with red caudal and white pectoral fins, white dot in front of snout really looks like "rabbit's head". saddle shaped dark patches along the back. Female drape color with large belly and horizontal dark bar along the body sides.
Not easy to watch close and keeping about 1 metre distance from me. Noted a male guarding a territory over big boulder, about 4-6m in range diametric. Bottom with smaller individuals and other goby species probably Favonogobius and/or Rhinogobius. Kuhlia and probably Lutjanus in midwater. Water plant scarce.
S. largocephalus mostly attached to rock and in gracing motion scraping attached algae/diatom/substrate from rock surface. Swimming motion by quick darting or longer distance straight motion. May hide in holes and substrates, dominant male in display around territory and chasing individuals especially males out.