Monday, February 20, 2023

[Ichthyology • 2022] Acanthopagrus oconnorae • A New Species of Seabream (Perciformes: Sparidae) from the Red Sea


  Acanthopagrus oconnorae Pombo-Ayora and Peinemann,

in Pombo-Ayora, Peinemann, Williams, He, Lin, Iwatsuki, Bradley & Berumen, 2022. 

 Abstract
A new species of sparid fish, Acanthopagrus oconnorae, is described based on 11 specimens collected in the shallow (0–1 m depth) mangrove-adjacent sandflats of Thuwal, Saudi Arabia. The new species is distinguished from its congeners by the following combination of characters: second anal-fin spine 12.8%–16.6% of standard length (SL); 3½ scale rows between the fifth dorsal-fin spine and lateral line; suborbital width 5.7%–6.7% of SL; eyes positioned at the anterior edge of the head, often forming a weakly convex break in an otherwise gently curved head profile, when viewed laterally; caudal fin light yellow with black posterior margin (approximately half of fin); anal fin dusky grey, with posterior one-fifth of the fin light yellow; black streaks on inter-radial membranes of anal fin absent. The most similar species to A. oconnorae is Acanthopagrus vagus, which differs by the presence of a w-shaped anterior edge of the scaled predorsal area, a more acute snout and black streaks on the inter-radial membranes of the anal fin. Phylogenetic placement and species delimitation of A. oconnorae are discussed based on COI, CytB and 16S sequences. It is hypothesized that ecology and behaviour explain how this species avoided detection despite its likely occurrence in coastal areas of the Red Sea with historically high fishing pressure.

Keywords: biodiversity, new species, phylogeny, Red Sea, seabream, Sparidae, taxonomy 


(a) Freshly collected holotype of Acanthopagrus oconnorae sp. nov., CAS-ICH 247294, 222.7 mm SL (standard length), from the central Saudi Arabian Red Sea.
(b) Holotype of A. oconnorae sp. nov. after preservation in formalin. The posterior margin of the preopercle and opercle turns darkish or blackish, and yellowish portions of pectoral, anal and pelvic fins turn hyaline after preservation.
Photos: L. Pombo-Ayora

Species of Acanthopagrus similar to Acanthopagrus oconnorae currently known from the Western Indian Ocean region.
(a) Acanthopagrus oconnorae sp. nov. [CAS-ICH 247299, 185.8 mm SL (standard length), Thuwal, Red Sea]. (b) Acanthopagrus sheim (168.3 SL, Dammam fish market). (c) Acanthopagrus vagus (200 mm SL, Kosi Bay, South Africa; specimen not retained). Note the differences in the colouration of the dorsal fin and anal fin. See Table 2 for detailed morphometric comparisons.
Photos: (a, b) L. Pombo-Ayora, (c) Bruce Mann

Acanthopagrus oconnorae Pombo-Ayora and Peinemann, sp. nov.

Diagnosis: A. oconnorae is distinguished from its congeners by the following set of characters: dorsal fin XI, 11; anal fin III, 8; 4½ scale rows above lateral line; 3½ scale rows between fifth dorsal-fin spine and lateral line; suborbital width 6%–7% of SL; body moderately deep (40%–45% of SL); head length 29%–32% of SL; second anal-fin spine 13%–17% of SL; anal fin yellowish grey or dusky grey, with posterior one-fifth of the fin light yellow; black streaks on inter-radial membranes of anal fin absent; caudal fin light yellow with a broad black posterior margin (approximately half of the fin); vertical bands on body absent or weak (four horizontal scale rows wide, if present); conspicuous black spot on the upper base of pectoral fin; diffuse black blotch at the origin of lateral line covering the upper part of the cleithrum (Figure 4).

Distribution and habitat: Currently this species is known from the mangrove-adjacent sandflats and mangrove-encircled pools of Thuwal, Saudi Arabia, in the central Red Sea. All specimens were caught in very close proximity to the mangrove habitat. All the trapped specimens were captured on sandflat shelves with very shallow water (maximum 1 m depth at high tide) near coastal stands of mangroves (Avicennia marina). Individuals of A. oconnorae appear to commonly utilize a specific type of habitat, co-occurring with A. berda, R. haffara, Pomadasys argenteus, Gerres longirostris, Monodactylus argenteus, Albula glossodonta and Crenimugil crenilabis.

 Etymology: A. oconnorae is named in honour of Winefride Bradley (née O'Connor), botanist, on the occasion of her 90th birthday. D.D.C.B., her son, first noted several of the distinctive features of this fish in specimens caught while leisure fishing, and he provided a caudal-fin clipping for initial genetic analysis. D.D.C.B. collected the first specimen (CAS-ICH 247295) analysed in this study.

  Common name: The following common name is proposed: Bev Bradley's Bream, after D.D.C.B.'s wife, Mrs. Beverley Bradley.



Lucía Pombo-Ayora, Viktor N. Peinemann, Collin T. Williams, Song He, Yu Jia Lin, Yukio Iwatsuki, Donal D. C. Bradley and Michael L. Berumen. 2022. Acanthopagrus oconnorae, A New Species of Seabream (Sparidae) from the Red Sea. Journal of Fish Biology. DOI: 10.1111/jfb.15147