NO. 3582 GENUS ENTOMACRODUS — SPRINGER 145 



Distribution (fig. 10). — Entomacrodus t. thalassinus is an island 

 form known from the Seychelles, Indian Ocean, and in the Pacific 

 Ocean from the Ryukyus to Raroia. Collection data indicate that 

 this subspecies occurs on the outer (ocean) sides of reefs along surge 

 or open channels. 



Material.— INDIAN ocean: Seychelle Islands: ANSP 102184, 102185. 



PACIFIC ocean: Ryukyu Islands: ANSP 72049 (holotype of S. lacunicola) ; 

 Marianas Islands, Guam: USNM 124193; Saipan: USNM 149914, SU 62076, 

 62081; Caroline Islands, Ifaluk: SU 62026, 62032, 62034, 62036, 62045, 62046; 

 Marshall Islands, Bikini: USNM 142184, 142185, 142190; Eniwetok: USNM 

 142186, 142187; Kapingamarangi : SU 62028, 62040; Phoenix Islands, Rowland: 

 USNM 179904; Enderbury: USNM 115480, 197908; Hull: USNM 115477, 

 116173; McKean: USNM 198591; Jarvis Island: USNM 198652; Maiden Island: 

 USNM 199458; Samoan Islands, Tutuila: USNM 115478; Samoa: SU 8693, 

 USNM 51795 (holotype of A. thalassinus), USNM 51790 (includes holotype of 

 A. musilae); Swains Island: USNM 115479; Tuamotus, Raroia: SU 62010, 

 62015, 62018, 62020, 62024, 62025. 



Entomacrodus thalassinus longicirrus, new subspecies 



Plate 29 



Discussion. — E. t. longicirrus differs from E. t. thalassinus pri- 

 marily in ha\'ing a much longer supraorbital cirrus (fig. 11). There 

 are minor differences in color pattern, which are manifested in E. t. 

 longicirrus ha\dng more melanic pigment. The new subspecies 

 appears to attain a larger size than the nominal subspecies. 



Distribution (fig. 10). — E. t. longicirrus is an island form restricted 

 to the South China Sea and its extension, the Gulf of Thailand. 

 This area is more or less enclosed by a chain of closely approximated 

 islands extending from Taiwan to Sumatra (see "Distribution" under 

 the nominal subspecies). A South China Sea endemic subspecies is 

 also indicated for E. stellifer. 



Holotype. — SU 62089, a mature male, 40.7 mm SL, shore reef 

 region on east side at Goh Kram Island, east side Gulf of Thailand, 

 12°41'33"N, 100°48'28"E, Oct. 25, 1957, collected by R. R. Rofen. 



Paratypes.— SU 63345, 45 specimens, and USNM 199480, 10 

 specimens, all with same data as holotype. SU 62001, 10 specimens, 

 South China Sea, Hot du Sud, 10°29'15"N, 108°57'30"E; SU 62092, 

 4 specimens. Gulf of Thailand, Go Samet Island, 12°31'15"N, 

 101°26'45"E; SU 62009, 1 specimen. Gulf of Thailand, rocky shore 

 reef in Ao Mae Hat Bay, Goh Tao Island; SU 62048, 12 specimens, 

 Viet Nam, neighborhood of Nahtrang, Binchang Bay, 12''21'40"N, 

 109°15'38"E; USNM 197978, 3 specimens. Hong Kong, Shelter 

 Island. 



Etymology. — From Latin, "longi" (long) + "cirrus" (a curl) refers 

 to the distinguishing characteristic of a long supraorbital cirrus. 



