Type locality, Banggai Is. (holotype of Pterapogon kauderni) (Ref. 48635). Recorded to have its natural distribution limited to the Banggai Arch., off the east coast of central Sulawesi (Celebes) and a few nearby islands. Apparently populations outside area of endemism (Lembeh Straits, Luwuk and Tumbak, Mamboro in Palu Bay) resulted from releases made by traders (Ref. 87100). This is correlated with its lack of pelagic larval stage. Fully developed juveniles (ca. 10 -11 mm TL) are expelled from the male's mouth. The young are apparently protected by the male parent for the first few weeks and presumably spend more time outside the mouth with increasing growth (Ref. 9936). Population recorded off Sarena I. (Lembeh Strait in North Sulawesi) in 2000, were found sheltering about 83% in the sea urchin Diadema setosum; 15% in anemones Heteractis crispa, Macrodactyla doreensis, and Actinodendron sp.; and 2% in hard corals Acropora horrida, Seriotopora hystrix and Heliofungia actiniformis (Ref. 43647). The Mamboro, Pulu Bay population were found in an area of lower salinity and an almost total lack of Diadema sea urchins; the substrate is silty sand, with seagrass and outcrops of corals and sponges. Group sizes ranged from 2-over 200 fish, the majority of which consists of similar size/age class. Large juvenile and adult fish would swim lazily near the coral outcrops, among seagrass leaves, and in relatively open spaces between suitable refuges at depths of 0.5-3 m. All small (<2 cm SL) juveniles observed were found in or near sea anemones, with or without anemone fish. This population appears to be exploited when 3-4 cm SL (size preferred by the trade) since these were periodically rare, whereas juvenile and larger adults were abundant on all visits (Ref. 87100). Museum: RMNH 17003. WAM P.30887-001 (45: 8-50mm SL). Also Ref. 45560, 47567, 90102.