Centropomus irae Carvalho-Filho, Oliveira, Soares & Araripe, 2019

Figueiredo-Filho, Jessé Miranda De, Marceniuk, Alexandre P., Feijó, Anderson, Siccha-Ramirez, Raquel, Ribeiro, Giovana S., Oliveira, Claudio & Rosa, Ricardo S., 2021, Taxonomy of Centropomus Lacépède, 1802 (Perciformes: Centropomidae), with focus on the Atlantic species of the genus, Zootaxa 4942 (3), pp. 301-338 : 320-321

Centropomus irae Carvalho-Filho, Oliveira, Soares & Araripe, 2019

( Figure 12 )

Type. MPEG 30613, 326 mm SL ( Fig. 12 ), loc.: Brazil, Amapá, Oiapoque, Baía do Oiapoque (Lat. 3.84/Long. - 51.82), ex coll.: A. Costa and J. Oliveira, 23 February 2014 .

Diagnosis. Centropomus irae has the highest number of scales in lateral line when compared to all congeners. In addition, it can also be differentiated from congeners as follows:

Western Atlantic: from C. undecimalis , by having 79–96 scales on lateral line to caudal-fin base (vs 66–75), and 7–8 low limb gill rakers on first arch (vs 8–11); from C. parallelus , by having 79–96 scales on lateral line to caudalfin base (vs 64–70), 7–8 lower limb gill rakers on first arch (vs 10–13), 11–13 gill rakers on first arch (vs 13–18), the longest anal-fin spine when close to body (adpressed) not reaching caudal-fin base (vs longest anal-fin spine usually reaching caudal-fin base), pelvic fin not reaching the anus (vs pelvic fin reaching the anus), and a more elongate and low body, with a mean body height of 22.3% SL (vs less elongate and higher body, with a mean body height of 26.6% SL; from C. ensiferus , by having 79–96 scales on lateral line to caudal-fin base (vs 48–58), 7–8 lower limb gill rakers on first arch (vs 10–15), 11–13 gill rakers on first arch (vs 15–20), the longest anal-fin spine when close to body (adpressed) not reaching caudal-fin base (vs longest anal-fin spine reaching caudal-fin base), and a more elongate and lower body, with a mean body height of 22.3% SL (vs less elongate and higher body, with a mean body height of 25.9% SL); from C. pectinatus , by having 79–96 scales on lateral line to caudal-fin base (vs 47–52), 7–8 lower limb gill rakers on first arch (vs 14–16), by 11–13 gill rakers on first arch (vs 20–23), the longest anal-fin spine when close to body (adpressed) not reaching caudal-fin base (vs longest anal-fin spine usually reaching caudal-fin base), pelvic fin not reaching anus (vs pelvic fin reaching anus), a more elongated and lower body, with a mean body height of 22.3% SL (vs less elongate and higher body, with a mean body height of 26.6% SL), and anal fin with III,7 (vs III,8); from C. poeyi , by having 79–96 scales on lateral line to caudal-fin base (vs 69–74), 7–8 lower limb gill rakers on first arch (vs 9–12), 11–13 gill rakers on first arch (vs 15–18), and second dorsal fin with I,11 (vs I,9).

Eastern Pacific: from C. nigrescens , by having 79–96 scales on lateral line to caudal-fin base (vs 68–76), and 7–8 lower limb gill rakers on first arch (vs 8–9); from C. viridis , by having 79–96 scales on lateral line to caudal-fin base (vs 67–75), 7–8 lower limb gill rakers on first arch (vs 9–12), 11–13 gill rakers on first arch (vs 14–15), and second dorsal fin with I,11 (vs I,9); from C. armatus , by having 79–96 scales on lateral line to caudal-fin base (vs 47–59), 7–8 lower limb gill rakers on first arch (vs 11–12), 11–13 gill rakers on first arch (vs 15–17), and the longest anal-fin spine when close to the body (adpressed) not reaching caudal-fin base (vs longest anal-fin spine reaching caudal-fin base); from C. robalito , by having 79–96 scales on lateral line to caudal-fin base (vs 47–59), 7–8 lower limb gill rakers on first arch (vs 14–17), 11–13 gill rakers on the first arch (vs 21–25), and the longest anal-fin spine when close to body (adpressed) not reaching caudal-fin base (vs longest anal-fin spine reaching caudal-fin base); from C. unionensis , by having 79–96 scales on lateral line to caudal-fin base (vs 46–52), 7–8 lower limb gill rakers on first arch (vs 10–14), 11–13 gill rakers on first arch (vs 15–20), and second dorsal fin with I,11 (vs I,9); from C. medius , by having 79–96 scales on lateral line to caudal-fin base (vs 53–65), 7–8 lower limb gill rakers on first arch (vs 14–16), 11–13 gill rakers on first arch (vs 18–23), and anal fin with III,7 (vs III,8).

Molecular data. Specimens of C. irae form a strong supported cluster in the COI sequences analysis, with 100% bootstrap value ( Figure 8 ). The genetic distance between this species to C. armatus is 0.187 and to C. ensiferus is 0.191 ( Table 7). Centropomus irae is genetically the sister group of C. undecimalis .

Description. Morphometrics and meristics data are summarized in Tables 8, 9 and 10 on the basis of 16 specimens, 171–330 mm TL (240 mm average). Body elongate, largest specimen measured 265 mm SL, head compressed and low, head height 20.4% SL (18.1%–22.0%); body very low, body height 22.3% SL (20.2%–23.9%). Head length comprising 37.7% (36.6%–40.0%) of SL. Lower jaw protractile, longer than upper jaw, extending beyond tip of snout. Snout narrow and long, snout length 12.0% SL (11.3%–12.7%); eye very small, mean orbital diameter 6.8% HL. Preoperculum serrated in adults; operculum smooth, without spines, bordered by a membrane that extends beyond origin of pectoral fin. Presence of small spines in dorsal part of operculum. Caudal peduncle long, mean caudal peduncle length 19.6% SL (18.3%–21.8%).

Dorsal fins separated by a small gap, not connected by membrane, first dorsal fin VIII, second dorsal fin I,11. Pectoral fin with 13–15 rays, longest ray 16.1% SL (13.3%–17.7%), extending beyond origin of pelvic fin and first dorsal fin. Pelvic fin with I,5, longest ray not reaching anus. Anal fin with III,7–III,8, longest spine not reaching caudal-fin base when adpressed, longest spine of anal fin 18.3% (15.8%–23.3%) of SL. Caudal fin deeply forked. Dark lateral line, linear, with ctenoid scales extending onto caudal fin. Lateral line with 79–96 scales to caudal-fin base. Scale rows between lateral line and origin of second dorsal fin 8–9; scale rows between lateral line and origin of anal fin 10–12. 7–8 lower limb gill rakers on first arch; 4–5 upper limb gill rakers on first arch; 11–13 gill rakers on first arch, excluding rudiments; 12–20 gill rakers on second arch, including rudiments.

Distribution. Centropomus irae is endemic to the north coast of Brazil, known from the state of Amapá, in Oiapoque river estuary, to Pará.

Remarks. Oliveira et al. (2014) firstly suggested the existence of an undescribed species of Centropomus , similar to C. undecimalis , in the north coast of Brazil. This species was later described as Centropomus irae by Carvalho-Filho et al. (2019) based on morphological traits and a partial sequence of the mitochondrial 16S gene. However, the description of C. irae was mostly based on the characters proposed by Rivas (1986), such as color of lateral line, interorbital width, snout length, orbital diameter, mandible length, which are non-informative characters to differentiate species of Centropomus .

Figures

FIGURE 8. Best maximum likelihood tree of Centropomus species elaborated with partial COI sequences. Numbers in the branches represent the percentage of occurrence of each group in 1000 pseudoreplicates by bootstrap. Values lower than 50% are not showed. Log likelihood = -3507.12.

FIGURE 12. Holotype of Centropomus irae. MPEG 30613, Amapá, Oiapoque, Brazil. 326 mm SL. Photo: Cintia Oliveira Carvalho, MPEG.