Friday, February 17, 2017

[Ichthyology • 2017] Acanthurus albimento • A New Species of Surgeonfish (Acanthuriformes: Acanthuridae) from northeastern Luzon, Philippines, with Comments on Zoogeography


Acanthurus albimento 
 Carpenter, Williams & Santos, 2017

  OceanScienceFoundation.org 

Abstract

Acanthurus albimento is described as a new surgeonfish from northeastern Luzon from six specimens collected during extensive fish-market surveys in the Philippines.The new species is characterized by a distinctive white band below the lower jaw; many irregular, wavy, thin, blue lines on the head; a brown-orange pectoral fin with a bluish tinge on the outer membrane of the rays and a dark band on the posterior margin; a narrow rust-orange stripe along the base of the dorsal fin; and a large blackish caudal spine and sheath with the socket broadly edged in black. An analysis using the mitochondrial cytochrome c oxidase subunit 1 (COI), supported by an independent multi-locus analysis, suggests phylogenetic affinities with an Acanthurus clade that includes A. auranticavusAbariene, A. blochii, A. dussumieri, A. gahhm, A. leucocheilus, A. maculiceps, A. mata, A. nigricauda, and A. xanthopterus; a clade that shares a suite of color characteristics. Based on the sampling history in the region, the new species may be a limited-range endemic in the westernmost Pacific Ocean, which is unusual for members of this genus. This raises potential questions about drivers of dispersal and long-held assumptions about zoogeographic patterns along the Kuroshio Current.

Acanthurus albimento, n. sp.

[upper] fresh paratype, USNM 438101, 226.6 mm SL, northeast Luzon, Philippines
[lower] fresh holotype, PNM 15199, 252.4 mm SL, northeast Luzon, Philippines.
photos: J.T. Williams.
      
Acanthurus albimento, n. sp. 
Whitechin Surgeonfish

Etymology. The new species is named albimento for its distinctive white chin. The specific epithet is derived from a combination of white (Latin albus) and a variation of the word for chin (Latin mentum), and is treated here as a noun in apposition


Kent E. Carpenter, Jeffrey T. Williams and Mudjekeewis D. Santos. 2017.
Acanthurus albimento, A New Species of Surgeonfish (Acanthuriformes: Acanthuridae) from northeastern Luzon, Philippines, with Comments on Zoogeography.
Journal of the Ocean Science Foundation. 25 33–46.