Sparisoma choati, Rocha, Luiz A., Brito, Alberto & Robertson, Ross, 2012

Rocha, Luiz A., Brito, Alberto & Robertson, Ross, 2012, Sparisoma choati, a new species of Parrotfish (Labridae: Scarinae) from the tropical eastern Atlantic, Zootaxa 3152, pp. 61-67 : 62-66

Sparisoma choati sp. n.

West-African Parrotfish

( Figures 1–2 AB, Table 1 )

Scarus squalidus (non Poey) Capello, 1872; Osório, 1890.

Sparisoma flavescens (non Bloch & Schneider) Fowler, 1936.

Sparisoma rubripinne (non Valenciennes) Randall, 1981; Sanches, 1991; Afonso et al. 1999; Brito et al., 1999; Bernardi et al., 2000; Robertson et al., 2006; Wirtz et al., 2007.

Holotype. CAS 224080, female, 128.8 mm total length, Atlantic Ocean, São Tomé and Principe, northeastern coast of São Tomé Island, dock near airport, 0°22'27" N, 6°43'03" E, 1 m depth, hook and line, 0 1 May 2006, Tomio Iwamoto.

Paratypes. CAS 214635, female, 114.8 mm, Atlantic Ocean, São Tomé and Principe, off Marlin Beach Hotel, 0°21'54" N, 6°42'48" E, 2–4 m depth, large beach seine by local fishermen, 12 April 2001, Tomio Iwamoto. CAS 230969, female, 100.6 mm, Atlantic Ocean, São Tomé and Principe, fish market at Gamboa and Mercado Municipal in São Tomé town, beach seine, 10 Jan 2009, David Catania and John McCosker. UF 179646, 245.2- 366.4 mm (2 terminal phase males, 2 females), Atlantic Ocean, Senegal, Dakar fish market, 10 m depth, trawling, 15 Sep 2005, Alberto Brito.

Diagnosis. Sparisoma choati can be distinguished from all of its congeners by the following combination of characters: Dorsal rays IX, 10; anal rays III, 9; pectoral rays 12 or 13 (rarely 13); pelvic rays I, 5; lateral line scales 23 to 26; gill rakers on first arch 11 to 14. Initial phase individuals and females greyish brown to greyish red, with chin and belly paler and reddish brown scales irregularly distributed singly or in clusters along flanks; pectoral fin translucent red with a dark red to black spot on upper fourth of its base. Terminal phase individuals with brownish red head and upper half of anterior two-thirds of body; ventral portion of central third of body yellowish green; posterior third of body dark greenish gray; black spot on upper fifth of pectoral fin base.

Description. Dorsal rays IX, 10; anal rays III, 9; all dorsal and anal soft rays branched, the last to base; pectoral rays 12 (13 in 1 specimen); pelvic rays I, 5; lateral line scales 23 to 26, including 2 or 3 on caudal-fin base; scales between lateral-line scales and origin of anal-fin 5 or 6; 2 rows of scales between lateral-line scales and dorsal fin, scales in upper row about half the size of those in lower row; 5 scales on cheek in single row; median predorsal scales 4, those scales progressively smaller and more ridged posteriorly, the last three progressively more notched posteriorly; median prepelvic scales 3; gill rakers on first arch 11 to 14.

Body moderately deep, the depth 34.5 to 42% of SL, and compressed, the width 13.7 to 19.4% SL; head moderately large, the length 29.7 to 32.3% SL; snout length 9.3 to 15.2% SL; orbit diameter 5.3 to 7.9% SL; interorbital width 6.2 to 8.1% SL; caudal peduncle depth 12.3 to 14.3 % SL; caudal peduncle length 12 to 15.2% SL. Mouth oblique and terminal, the lower dental plate overlapping the upper; lips covering at least half of dental plates.

Origin of dorsal fin slightly posterior to upper end of gill opening, the predorsal length 29.3 to 34.7% of SL; dorsal and anal spines flexible, the tips curving posteriorly; first dorsal spine 8.2 to 12.5% SL; origin of anal fin below base of last dorsal spine; pectoral fins slightly pointed, the second ray the longest; pelvic fins pointed, the second ray the longest, the prepelvic length 28.2 to 33.3% SL; caudal fin truncate in juveniles and females, slightly lunate in terminal males, the concavity 1.6 to 3.8% SL.

Color of holotype in alcohol as in Figure 1 . Preserved initial phase specimens uniformly light to dark brown, darker dorsally, with fins the same color as body. Terminal phase specimens also brown, with a darker posterior third of body and dark spot on pectoral upper fifth of pectoral fin usually visible. Color in life as shown in Figure 2 A and 2B. Initial phase individuals grayish brown to greyish red, with chin and belly paler and some reddish brown scales irregularly distributed along flanks, giving the fish an overall mottled pattern; edges of scales dark; fins greyish to whitish red, except for pectoral fin, which is translucent red with a dark red to black spot on upper fourth of its base; iris orange. Terminal phase individuals with brownish red head and upper half of anterior twothirds of body, ventral portion of head and body paler; cheek with a gray cast; ventral portion of central third of body bright yellowish green; posterior third of body dark greenish gray; sometimes scales with thin bright green margin; posterior third of dorsal fin and caudal fin dark gray, anal fin greenish blue, anterior two-thirds of dorsal fin red brown, pectoral fin brownish red with yellowish green base and a black spot on upper fifth of that fin base, ventral fin brownish red anteriorly and greenish blue posteriorly.

Habitat and distribution. Sparisoma choati is distributed from the Cape Verde islands and Senegal south to the offshore islands of the Gulf of Guinea and northern Angola ( Figure 3 ). It has been observed in rocky reefs from depths of 2 to 30 m where it grazes on algae growing over rocky or calcareous substrate. Males are usually solitary, but females are often seen in pairs or small groups and juveniles in lose aggregations of up to 10 individuals.

Remarks. Sparisoma choati is part of a monophyletic clade that also includes the Caribbean Sparisoma rubripinne and the Brazilian Sparisoma axillare . The three species in this clade are indistinguishable morphologically, but are easily separated by color pattern, genetics and areas of distribution. Terminal male S. rubripinne have a dull green or blue-green body, and TP S. axillare have a brown to greenish-brown body. In contrast TP S. choati have a distinguishing tri-colored body. Initial phase male and female S. rubripinne have a bright yellow tail and two vertical pale bars crossing the chin, and IP S. axillare have bright yellow scales irregularly distributed over a pale brown body. IP S. choati , however, have a greenish-gray body with irregular reddish-brown scales along the sides and red fins ( Figure 2 ). Phylogenetic analyses indicate that S. choati (labeled as S. “ rubripinne ”) is sister to a monophyletic clade containing S. rubripinne and S. axillare ( Robertson et al., 2006) . DNA sequences obtained for the type series of S. choati also confirm their genetic identity as belonging to the clade labeled as S. “ rubripinne ” by Robertson et al. (2006).

Within its area of occurrence, initial phase individuals of Sparisoma choati are somewhat similar in color to initial phase Nicholsina collettei , but these two species are easily distinguishable in the field upon close inspection. Moreover, N. collettei is rarely seen in rocky reefs since its preferred habitat is sandy areas with sea grass. Female and initial phase Sparisoma choati also can resemble juvenile and initial phase Sparisoma cretense : both are greyish brown with reddish fins. However, terminal phase male S. cretense have a distinguishing large black blotch just above and behind the pectoral fin base, and a more pointed head, and juveniles have a brownish red body (greyish in S. choati ) and pale bars crossing the chin.

Etymology. We name this species in honor of J. Howard Choat, in recognition of his extensive scientific work on parrotfishes. During his lengthy and productive career, Howard has made many significant contributions to our knowledge of parrotfish taxonomy, ecology, reproductive biology, demography, evolution and historical biogeography.

Figures

FIGURE 1. Lateral, dorsal and ventral views of the holotype of Sparisoma choati, CAS 224080. Photos by J. Fong.

FIGURE 2. Underwater photographs of a terminal phase male Sparisoma choati (A, São Tomé), initial phase S. choati (B, São Tomé), TP S. rubripinne (C, Bahamas), IP S. rubripinne (D, Belize), TP S. axillare (E, Brazil), and IP S. axillare (F, Brazil). Photo credits: L. Rocha (A, B); F. Charpin (C); J. Randall (D); J. P. Krajewski (E); O. Luiz (F).

FIGURE 3. Geographic distributions of Sparisoma choati (*), S. rubripinne (□) and S. axillare ().

Tables

TABLE 1. Total length, standard length (mm) and proportional measurements (% SL) of the type series of Sparisoma choati.

Specimen Total length	CAS 224080 Holotype 128.8	CAS 214635 114.8	CAS 230969 100.6	UF 179646-1 366	UF 179646-2 395	UF 179646-3 362	UF 179646-4 245
Standard length Body depth Body width Head length	108.5 38.5 14.8 32.3	97.5 34.5 14.6 29.7	82.4 37.5 13.7 30.2	288 42.0 19.1 31.9	314 39.5 19.4 32.2	290 37.9 18.6 31.0	191 39.3 19.4 31.4
Snout length Orbit diameter	12.3 7.9	9.3 6.8	10.3 6.4	14.1 5.3	15.2 5.3	13.5 5.5	12.3 6.5
Interorbital width Caudal ped depth Caudal ped length Predorsal length	8.1 13.5 14.4 34.1	6.9 12.3 15.2 29.3	7.9 12.4 13.0 34.0	6.6 13.2 13.1 34.7	6.6 12.3 13.7 34.7	6.2 12.5 12.0 33.4	7.0 14.3 12.7 33.4
Prepelvic length Dorsal fin base	32.3 58.4	28.2 52.9	28.6 54.5	32.5 61.5	33.3 52.5	31.5 57.2	32.2 59.8
Anal fin base First dorsal spine 9th dorsal spine 3rd anal spine	31.0 10.9 10.1 8.1	32.5 10.6 9.4 8.2	28.3 8.3 6.8 7.3	21.4 9.9 11.5 9.0	27.6 12.5 11.1 9.1	25.2 11.9 10.4 9.3	27.0 11.7 10.7 9.4
Longest anal ray	10.7	11.3	8.7	12.2	14.3	12.7	13.9