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.
摘要:
一种新的鱼,刺五加,根据在Thuwal的浅层(0-1m深度)红树林附近的沙地中收集的11个标本进行描述,沙特阿拉伯。新物种通过以下特征组合与其同源物区别开来:第二肛鳍脊柱为标准长度(SL)的12.8%-16.6%;第五背鳍脊柱和侧线之间的3½刻度行;SL的眶下宽度5.7%-6.7%;眼睛位于头部的前边缘,通常在原本轻轻弯曲的头部轮廓中形成弱凸断裂,侧面观察时;尾鳍浅黄色,后缘黑色(大约鳍的一半);肛门鳍灰白色,鳍的后部五分之一为浅黄色;肛门鳍的radial膜上没有黑色条纹。与O.connorae最相似的物种是迷走神经刺五加,其不同之处在于缩放后的背前区域的w形前缘的存在,肛门鳍的桡骨膜上有更尖锐的鼻子和黑色条纹。基于COI讨论了oponnorae的系统发育位置和物种划分,CytB和16S序列。据推测,生态学和行为可以解释该物种如何避免被发现,尽管它可能发生在具有历史较高捕捞压力的红海沿海地区。