Bioacoustics of Choerodon margaritiferus

Etymology. The English name “Pearly Tuskfish” follows Allen and Erdmann (2012) . The word “Yuumodoro” used in the new standard Japanese name means the scene of sunset at Motobu town, near our collecting site, in the Okinawan local song. The red blotch and blue lateral stripe in the male suggest a sunset over the ocean. In addition, the word “Bera” means wrasse fish in standard Japanese. Identification. Choerodon margaritiferus Fowler and Bean, 1928 was originally described on the basis of 1 specimen ( Holotype : USNM 89966) collected from Jolo, the Philippines . Counts and measurements of examined specimens agree closely with those of the holotype (see description and Table 1 ). Although the body color of the holotype has mostly faded, some diagnostic coloration remained in the form of white marks: a lateral stripe under the eye, a row of spots on the mid-lateral part of the body, a lateral stripe on the middle of the caudal peduncle, and a bar on the pectoral-fin base ( Fig. 1 C). These color patterns matched well with those of the examined male specimen (see Figs. 1 A, C). In addition, the coloration of the holotype as described agrees almost exactly with that of the specimen. The only point of difference is that the notable red blotch in our male specimen was not noted in the original description. Fowler and Bean may have not observed it, because this character easily vanishes during preservation. In the genetic analysis, the partial sequence of COI of examined specimens and 6 comparative species were aligned at 626 sites, 184 of which were polymorphic. The neighbor-joining dendrogram derived from the aligned sequences showed that the described specimens and C . margaritiferus ( KM224711 , from Indonesia , identified by Puckridge et al ., 2015 ) represent the same clade ( Fig. 3 ). No genetic differences were found between the two color types (male and female) of examined specimens. Thus, examined specimens in this study were regarded as the same species. Meanwhile, other comparative species clearly represented separate clades with 78–100% bootstrap probability. This result emphasizes that the specimens collected from Okinawan waters were identified correctly as C . margaritiferus . Choerodon margaritiferus Pectoral-fin rays 14 14 14 14 14 15 Pelvic-fin rays I, 5 I , 5 I , 5 I , 5 I , 5 I , 5 Principal caudal-fin rays 14 14 14 14 14 14 Upper procurrent caudal rays 7 7 8 7 7 8 ......continued on the next page Holotype Non-type specimens from Okinawan waters Holotype USNM 89966 male Non-type specimens from Okinawan waters OCF-P OCF-P OCF-P 20140827-1 20140825-3 20140827-2 male Female female OCF-P 20140827-3 female OCF-P 20140827-4 female Standard length (mm) 116.0 107.0 96.4 103.0 94.5 97.4 Counts Dorsal-fin rays Anal-fin rays XII, 8 III, 10 XII, 8 XII, 8 XII, 8 III, 10 III, 10 III, 10 XII, 8 III, 10 XII, 8 III, 10 Lower procurrent caudal rays Pored lateral-line scales Scales between lateral line and 1st dorsal-fin spine 7 27+2 3 ½ 7 27+2 2 ½ 7 7 27+1 27+2 2 ½ 2 ½ 7 27+2 2 ½ 7 27+2 2 ½ Scales between lateral line and 5th dorsal-fin spine 2 ½ 2 ½ 2 ½ 2 ½ 2 ½ 2 ½ Scales below lateral line Median predorsal scales Median prepelvic scales Rows of scales on rear portion of cheek 7 ½ 8 8 3 7 ½ 8 8 3 7 ½ 8 ½ 7 7 7 7 3 3 7 ½ 7 7 3 7 ½ 6 8 3 Scales on interopercle Circumpeduncular scales Gill rakers Vertebrae Single row of 6 16 6+11 27 Single row of 8 16 6+10 27 Single row of 7 Single row of 7 15 16 5+10 6+10 27 27 Single row of 6 16 6+11 27 Single row of 6 15 6+10 27 Measurements (% of SL) Body depth Body width Head length 28.6 20.3 36.4 27.4 18.6 39.1 25.2 25.9 18.8 19.5 38.0 38.2 25.8 19.4 38.6 26.1 19.0 38.1 USNM OCF-P OCF-P OCF-P OCF-P OCF-P 89966 20140827-1 20140825-3 20140827-2 20140827-3 20140827- 4 male male Female female female female