Pyrgoma projectum Nilsson-Cantell, 1938

Ross, A. & Newman, William A., 2002, A review of the Pyrgoma cancellatum species complex (Cirripedia: Pyrgomatidae), Journal of Natural History 36 (4), pp. 407-421 : 415

Pyrgoma projectum Nilsson-Cantell, 1938

Pyrgoma projectum Nilsson-Cantell, 1938: 70 , ®gure 27, pl. 3, ®gure 4; Utinomi, 1969: 82

(listing). Nobia projectum: Ross and Newman, 1973: 155 , ®gure 12i, j; Newman and Ross, 1976: 58

(references). Paranobi a projectum: Galkin, 1986: 1283 . not Nobia projectum: Anderson, 1992: 303 (= Arossella lynnae Ross, 2000 ). not Rossia projectum: Anderson, 1992: 329 (= Arossella lynnae Ross, 2000 ). Nobia projecta [sic]: Ogawa and Matsuzaki, 1992: 95.

Diagnosis. Wall with 20±25 coarse radiating ribs; articular furrow of scutum narrow, relatively shallow, limbus adductorum about one-quarter overall height; tergum broad, longitudinal furrow open, distal end of spur tapering to narrow blunt point, depressor muscle crests extending well beyond basal margin.

Type locality and host. Marine Survey of India station 352, oV Faylakah Island, Kuwait, Persian Gulf, 29ss30¾N, 48ss47¾E, 24 m, on Caryophyllia sp .

Type depository. Indian Museum , Calcutta, India, cat. no. 8313/10 .

Remarks. Although Nilsson-Cantell (1938) considered this species might be conspeci®c with P. kuri , there are several diVerences in the opercular plates. The most noticeable is the large size of the tergal depressor muscle crests that extend a short distance beyond the basal margin, and the spur termination is pointed not truncate as in P. kuri . Based on Nilsson-Cantell’s (1938) illustration the height to width ratio is about 1.35 1 whereas in P. kuri it is 1.80 1.

This species is perhaps more closely related to P. sinica . However, it diVers in the scutum questionably lacking a rostral tooth, and the tergal depressor muscle crests are seemingly simpler and do not extend as far beyond the basal margin.