(Fig. 1H)
Calcinus morgani Rahayu & Forest, 1999: 465, Figs. 1B, 2C, D, G, H, J (Sidangoli, Halmahera, Indonesia, type locality); Asakura, 2002: 43–48, Figs. 9 –11, Fig. 21E–I; McLaughlin et al., 2007: 159–161, 3 unlabelled figures; Malay & Paulay, 2010: Appendix S1.
Calcinus gaimardii – Haig & Ball, 1988: 159; Poupin 1997: 688– 690, Figs. 2B, 5D; Morgan, 1991: 876–878, Fig. 11 (in part, form II) [not Calcinus gaimardii (H. Milne Edwards, 1848)].
Calcinus gaimardi – Wooster, 1984: 131–133 (misspelling of Calcinus gaimardii).
Calcinus areolatus Rahayu & Forest, 1999: 468–471, Fig. 4 (Ambon, Indonesia, type locality).
Material examined. 2 ovig. females SL 4.0– 6.5 mm, 5 females SL 3.0– 4.4 mm, 8 males SL 1.8–7.0 mm (ZRC), stn M1, Alona Beach, Panglao I., 9°32.9′N, 123°46.6′E, 0–1 m, v.2004 to vii.2004; 1 ovig. female SL 4.8 mm (ZRC), stn M2, west end of Alona Beach, Panglao I., 9°32.8′N, 123°45.9′E, 0–2 m, 30.v.2004; 1 male SL 3.6 mm (ZRC), stn M2, west end of Alona Beach, Panglao I., 9°32.8′N, 123°45.9′E, 0–2 m, 30.v.2004; 2 females SL 2.5–4.0 mm (ZRC), stn M3, Danao, Panglao I., 9°32.5′/33.1′N, 123°44.7′/45.5′E, 0–2.5 m, 31.v.2004; 1 ovig. female SL 6.4 mm, 1 female SL 3.4 mm, 1 male SL 5.5 mm, 1 indiv. in shell (ZRC), stn M5, Doljo Point, Panglao I., 9°35.5′N, 123°43.3′/44.3′E, 0–2 m, v.2004 to vi.2004; 1 female SL 6.3 mm (ZRC), stn M18, Gak-Ang Islet, off Panglao I., 9°33.0′N, 123°45.5′E, 0–1 m, 10 & 12.vi.2004; 3 females SL 2.7–5.8 mm (ZRC), stn M20, Pamilacan I., 9°29.3′N, 123°55.1′E, 0–2 m, 13.vi.2004; 1 ovig. female SL 9.5 mm, 2 males SL 3.0– 6.5 mm (ZRC), stn M22, Napaling, Panglao I., 9°37.2′N, 123°46.4′E, 0–3 m, 15.vi.2004; 1 male SL 6.5 mm (ZRC), stn M58, Balicasag I., 9°31.3′N, 123°41.0′E, depth unknown, 4.vii.2004; 1 male SL 5.8 mm (ZRC), stn R11, Biking, Panglao I., 9°35.2′N, 123°50.5′E, 4 m, 2.vi.2004; 10 indivs. in shell (ZRC), stn R20, Cathedral, 9°31.1′N, 123°41.5′E, 7–48 m, 5.vi.2004; 1 ovig. female SL 5.6 mm, 1 female SL 5.0 mm (ZRC), stn R24, Bingag, Panglao I., 9°37.5′N, 123°46.8′E, 0–2 m, 6.vi.2004; 1 ovig. female SL 4.0 mm (ZRC), stn R59, Momo Beach, Panglao I., 9°36.2′N, 123°44.9′E, 2–20 m, 22.vi.2004; 1 male SL 5.3 mm (ZRC), stn R61, between Sao and San Isidro, Panglao I., 9°34.3′N, 123°49.3′E, 4–22 m, 23.vi.2004; 1 ovig. female SL 5.1 mm, 3 males SL 4.9–5.7 mm (ZRC), stn R73, Balicasag I., 9°30.9′N, 123°40.8′E, 2–30 m, 2.vii.2004; 1 male SL 5.2 mm (ZRC), stn S42, Pamilacan I., 9°30.1′N, 123°55.5′E, 15–20 m, 1.vii.2004.
Habitat. Intertidal to subtidal, 0 to approximately 12 m, reef flats, slopes, and ledges, on coralline, sandy, and mixed substrates.
Remarks. Calcinus morgani closely resembles and is easily mistaken for C. gaimardii (see remarks under C. gaimardii).