Comprehensive Description
(
Anglèis
)
fornì da Smithsonian Contributions to Zoology
Scarops rubroviolaceus (Bleeker)
Scarus rubroviolaceus Bleeker, 1849, p. 52.
Callyodon rubroviolaceus.—Smith, 1956, p. 11, pl. 43J.
Scarops rubroviolaceus.—Schultz, 1958, p. 21, pls. 3D, 6A.—Munro, 1967, p. 437, fig. 830 [New Guinea].
Callyodon (Scarops) rubroviolaceus.—Smith, 1959, pp. 270, 278, pl. 43J.
Pseudoscarus jordani Jenkins, 1900, p. 63, fig. 21.
Scarops jordani.—Schultz, 1958, p. 21, fig. 2, pls. 2C, 6B.—Hobson, 1965, p. 295.—Munro, 1967, p. 437, fig. 831 [New Guinea].
Callyodon africanus Smith, 1955, p. 19, fig. 26, pl. 3: fig. 26.
Margaritodon africanus.—Smith, 1956, p. 15, pl. 42A.
Callyodon (Margaritodon) africanus.—Smith, 1959, pp. 272, 280, pl. 42A.
Scarus africanus.—Schultz, 1958, p. 75, pls. 18E, 19E.
Scarus paluca Gosline and Brock, 1960, p. 237 [Hawaiian Islands].
See Schultz (1958, p. 21) for other synonyms.
Characterized by having 5 to 7 predorsal scales, 3 rows of scales on cheek, with 2 scales in ventral row, ii,13 pectoral rays, teeth white in young and females, blue or green in adult males; upper pharyngeal with a single enlarged row of teeth, rarely with a rudimentary row present.
Coloration of adult males: Edge of upper lip orange or red extending to below eye, then blue or green shading into brown above; edge of lower lip blue or green, thence a red or orange cross band, followed posteriorly by a blue or green cross band; lower part of head orange, usually with another blue or green blotch; edge of pelvic green; dorsal edge of pectoral green, and upper half purplish brown; distal edge of dorsal blue or green, remaining four-fifths of dorsal orange; distal half of anal blue or green, basal half orange or pink; outer edges of caudal fin green or blue; dorsal part of body orange to purplish, ventrally green or blue.
Coloration of adult females: Bright purplish red or dark brownish red, fins red, except pectoral, which is bluish with red streak dorsally, and dorsal fin is margined with dark blue distally. Nearly each scale dorso-laterally has one or more short blackish or brownish lengthwise streaks that remain visible on scales after many years of alcoholic preservation.
Juveniles reddish brown.
Margaritodon africanus Smith, 1956 (p. 15, pl. 42A), has an almost identical color pattern with that of the following specimens: USNM 202638 and 202641 (IIOE, FT–5, 20 November 1964, Latham Island, SE of Zanzibar, 2 spec., 400–490 mm). An examination of the upper pharyngeals of one of these specimens has revealed a single enlarged row of teeth as in Scarops. A comparison of the color pattern of Smith’s Plate 42A with the description of a mature male of jordani furnished by Dr. Rosenblatt in Schultz (1958, p. 22) indicates almost identical color patterns. Tentatively, in the absence of a description of the upper pharyngeals of africanus by Smith, I consider africanus as a junior synonym of jordani.
Briggs (1964, p. 707) reports Scarops rubroviolaceus from Cocos Island in the eastern Pacific, and Schultz (1958, p. 22) recorded S. jordani from Cocos Island also, as well as from Socorra Island and Roqueto Island. Schultz reports S. rubroviolaceus from the Hawaiian Islands, central and western Pacific Ocean, and Smith (1956, 1959) records it from the western Indian Ocean. The range, habitat, color patterns, and pharyngeal teeth indicate that only one species should be recognized and that rubroviolaceus is the female and jordani the mature male.
Mr. Howard Choat independently reached this same conclusion, which he stated in a letter to me dated 6 December 1965. Dr. John Randall, University of Hawaii, expressed the same opinion during a recent visit with me.
RANGE.—Hawaiian Islands, eastern, central, and western Pacific Ocean, and Indian Ocean.
Bolbometopon J. L. B. Smith, 1956, p. 8 [type-species: Scarus muricatus Cuvier and Valenciennes]; 1959, p. 269.
Cetoscarus J. L. B. Smith, 1956, p. 16 [type-species: Scarus pulchellus Rüppell] 1959, p. 274.
Smith (1959, p. 272) has shown that I incorrectly identified Scarus gibbus Rüppell, 1828, type-species of Chlorurus Swainson, 1839, from the Red Sea. It is S. microrhinos Bleeker. This important discovery places the genus Chlorurus as a synonym of the genus Scarus, which left two species of parrotfishes (Scarus muricatus Cuvier and Valenciennes, and Scarus bicolor Rüppell=Scarus pulchellus Rüppell) that formed a natural group without a generic name. Smith (1956, pp. 8, 16) established two new generic names, Bolbometopon and Cetoscarus, for them and, in 1959, he again recognized both genera as valid.
An analysis of the characters that Smith used to distinguish the two genera shows that the number of predorsal scales overlap as follows: muricatus has 4 or 5, bicolor 5 to 7; muricatus has ii,13 or ii,14 (usually ii,14) pectoral fin rays, whereas bicolor usually has ii,12 rarely ii,13 pectoral fin rays. These species have 3 series of scales on the cheek and according to Smith the ventral row in bicolor varies from 1 to 6, normally 3 to 6, whereas my counts range from 2 to 8 and that for muricatus 2 or 3.
Since the three characters (i.e., the number of predorsal scales, the pectoral fin rays, and the cheek scales) overlap, much like that for several species in the genus Scarus, I do not consider them as valid characters to distinguish genera; however, the pharyngeal mill (not mentioned by Smith, 1956 or 1959) distinguishes the two species in this relationship from all other species of parrotfishes as follows:
The upper pharyngeal bones bear 3 rows of teeth on each side: 2 inner rows of large teeth and an outer row of rudimentary teeth next to middle row; the lower pharyngeal plate has a concave dental surface as broad as long or a little longer than broad. No other parrotfish in the subfamily Scarinae has 3 rows of teeth; instead, they have only 1 or 2 rows of teeth on the upper pharyngeals, whereas all species of parrotfishes in the subfamily Sparisomatinae have 3 rows of teeth. I conclude, therefore, that Bolbometopon, with page priority, should be recognized as the valid genus for this relationship, and that Cetoscarus is a junior synonym.
RANGE.—Central and western Pacific Ocean, Indian Ocean, and Red Sea.
Bolbometopon muricatus (Cuvier and Valenciennes)
Scarus muricatus Cuvier and Valenciennes, 1839, p. 208, pl. 402.
Pseudoscarus muricatus.—Bleeker, 1862, p. 26, pl. 7: fig. 3.
Bolbometopon muricatus.—Smith, 1956, p. 8, pls. 42H, 45A-D; 1959, pp. 269, 278, pls. 42H, 45.—Munro, 1967, p. 437, fig. 829 [New Guinea].
Pseudoscarus frontalis [not Cuvier and Valenciennes].—Macleay, 1883, p. 590.
Callyodon macleayi Jordan and Seale, 1906, p. 331.
Callyodon shimoniensis Smith, 1953, p. 622, pls. 15, 16.
Chlorurus gibbus [not Rüppell].—Schultz, 1958, p. 26, pls. 1A, 7.
Characterized by having 4 or 5 median predorsal scales, 3 rows of scales on cheek, with 1 or 2 scales in ventral row; ii,14 pectoral fin rays, occasionally ii,13; lips not covering white teeth; snout with a nearly straight dorsal profile that bends abruptly over eyes; snout longer than postorbital length of head.
Coloration: Uniform brown; young and half-grown specimens with several white scales on sides; large adults have a fleshy knob on forehead over eyes.
RANGE.—Central and western Pacific Ocean, Indian Ocean, and Red Sea.
- sitassion bibliogràfica
- Schultz, Leonard P. 1969. "The taxonomic status of the controversial genera and species of parrotfishes with a descriptive list (family Scardiae)." Smithsonian Contributions to Zoology. 1-49. https://doi.org/10.5479/si.00810282.17
