Rhinogobius aonumai, Suzuki & Oseko & Yamasaki & Kimura & Shibukawa, 2022

Suzuki, Toshiyuki, Oseko, Naoharu, Yamasaki, Yo Y., Kimura, Seishi & Shibukawa, Koichi, 2022, A New Species with Two New Subspecies of Rhinogobius (Teleostei: Gobiidae) from Yaeyama Group, the Ryukyu Islands, Japan, Bulletin of the Kanagawa Prefectural Museum (Natural Science) 51, pp. 9-34 : 12-13

Rhinogobius aonumai sp. nov.

(New Standard Japanese name: Painu-kibarayoshinobori)

Holotype. OMNH-P 40256 , male, 65.9 mm SL, Hinai-gawa River , Iriomote-jima Island , the Yaeyama Group of the Ryukyu Islands, Japan, upper reaches above Pinaisara Fall (total vertical height 58.7 m), 24°22' 54.99"N 123°49' 13.29"E, 104 m above sea level, 19 Aug. 2012, Fig. 1 .

Paratypes. Total 28 specimens (15 males and 13 females, 35.9–70.5 mm SL), collected from Iriomote-jima Island. Aira-gawa River : OMNH-P 40849 ( Fig. 6B ) and 40852 ( Fig. 6A ), female and male, 42.3 and 47.5 mm SL, stained with Alizarin Red S., 24°20'54"N 123°54'1"E, 54 m above sea level, 7 May 2014 ; Geta-gawa River : OMNH-P 40832 ( Fig. 6C ) and 40836 ( Fig. 6D ), male and female, 58.0 and 40.5 mm SL, stained with Alizarin Red S., upper reaches above Geta Fall (total vertical height 32.7 m), 24°23'18.59"N 123°51' 36.09"E, 100 m above sea level, 6 May 2014 ; Hinai-gawa River : KPM-NI 59987 (formerly OMNH-P 40254 ), and 59988 (formerly OMNH-P 40255 ) ( Fig. 2 ), male and female, 66.0 and 56.5 mm SL, collected with the holotype ; OMNH-P 40257 , female, 61.5 mm SL, collected with the holotype ; OMNH-P 43694 , male, 70.5 mm SL, stained with Alizarin Red S., same locality with the holotype, 13 Aug. 1993 ; NSMT-P 138485 ( Fig. 6E ) and 138486 ( Fig. 6F ), male and female, 56.0 and 55.5 mm SL, stained with Alizarin Red S., collected with the holotype ; Kuira-gawa River : KPM-NI 59984 ( Fig. 6H ), 59985 ( Fig. 6G ) and 59986, female, male and female, 38.5, 35.9 and 39.0 mm SL, two females are stained with Alizarin Red S., 24°17'23.18"N 123°45'4.25"E, 30 m above sea level, 23 July 2003 ; Kura-gawa River : OMNH-P 43162 ( Fig. 6I ) and 43165 ( Fig. 6J ), male and female, 42.0 and 36.0 mm SL, stained with Alizarin Red S., upper reaches above Kura Fall (total vertical height 7.6 m), 24°23'53.07"N 123°50' 47.73"E, 15 m above sea level, 28 July 2015 ; Nakara-gawa River : OMNH-P 43153 ( Fig. 7A ) and 43156 ( Fig. 7B ), male and female, 47.3 and 37.0 mm SL, stained with Alizarin Red S., upper reaches above Nakara Fall (total vertical height 27.9 m), 24°19'30.16"N 123°47' 9.93"E, 52 m above sea level, 31 July 2015 ; Nishida-gawa River : OMNH-P 40533 ( Fig. 7C ) and 40537 ( Fig. 7D ), male and female, 58.3 and 50.3 mm SL, stained with Alizarin Red S., upper reaches above Sangara Fall (total vertical height 7.2 m), 24°23'1.37"N 123°49' 58.81"E, 30 m above sea level, 1 Aug 2013 ; Urauchi-gawa River : OMNH-P 40040 ( Fig. 7E ), male, 46.3 mm SL, upper reaches above Kampire Fall (total vertical height 13.0 m), 24°21'17.18"N 123°48' 27.00"E, 65 m above sea level, 28 March 2012 ; SPMN-PI 46248 (formerly OMNH-P 40042 ) and SPMN-PI 46249 (formerly OMNH-P40043 ) ( Fig. 7F ), male and female, 48.0 and 46.0 mm SL, collected with OMNH-P 40040 ; OMNH-P 43689 , 43690 , 43691 and 43796, three males and female, 51.3, 47.5, 51.1 and 47.5 mm SL, three males are stained with Alizarin Red S., upper reaches above Mariudo Fall (total vertical height 19.4 m), 24°21'25.49"N 123°48' 12.27"E, 34 m above sea level, 10 Aug 1993 ; Yuchin-gawa River : OMNH-P 40323 ( Fig. 7G ) and 40327 ( Fig. 7H ), male and female, 63.0 and 49.2 mm SL, stained with Alizarin Red S., upper reaches above Yuchin Right Falls (total vertical height 44.2 m), 24°21'58.82"N 123°53' 2.39"E, 253 m above sea level, 27 March 2013 .

Diagnosis. Rhinogobius aonumai is distinguished from all congeneric species by having the following combination of features: 9–15 predorsal scales; 32–38 longitudinal scales; 26–28 vertebrae, mode 27; sensory-papillae rows on cheek arranged longitudinally, with no transverse rows; yellow-colored body in freshly-collected; no dark spot on first dorsal fin; caudal fin with 4–14 and 3–10 vertical rows of dark spots or forming dark zigzag bands in males and females, respectively; a pair of short, vertically aligned, rod-shaped dark mark on caudal-fin base in females.

Figures

Fig. 1. Holotype of Rhinogobius aonumai aonumai (OMNH-P 40256, male, 65.9 mm SL) collected from Hinai-gawa River, Iriomotejima Island, the Ryukyu Islands, Japan.A and B: freshly-collected; C: alcohol-preserved. Photographed by T. Suzuki.

Fig. 6. Freshly-collected paratypes of Rhinogobius aonumai aonumai from Iriomote-jima Island, the Ryukyu Islands, Japan. Airagawa River: A (OMNH-P 40852, male, 47.5 mm SL) and B (OMNH-P 40849, female, 42.3 mm SL); Geta-gawa River: C (OMNH-P 40832, male, 58.0 mm SL) and D (OMNH-P 40836, female, 40.5 mm SL); Hinai-gawa River: E (NSMT-P 138485, male, 56.0 mm SL) and F (NSMT-P 138486, female, 55.5 mm SL); Kuira-gawa River G: (KPM-NI 59985, male, 35.9 mm SL) and H (KPM-NI 59984, female, 38.5 mm SL); Kura-gawa River: I (OMNH-P 43162, male, 42.0 mm SL) and J (OMNH-P 43165, female, 36.0 mm SL). Photographed by T. Suzuki.

Fig. 2. Female paratype of Rhinogobius aonumai aonumai (KPM-NI 59988, 56.5 mm SL) collected from Hinai-gawa River, Iriomotejima Island, the Ryukyu Islands, Japan.A and B: freshly-collected; C: alcohol-preserved.Photographed by T. Suzuki.

Fig. 7. Freshly-collected paratypes of Rhinogobius aonumai aonumai from Iriomote-jima Island, the Ryukyu Islands, Japan. Nakaragawa River: A (OMNH-P 43153, male, 47.3mm SL) and B (OMNH-P 43156, female, 37.0 mm SL); Nishida-gawa River: C (OMNH-P 40533, male, 58.3 mm SL) and D (OMNH-P 40537, female, 50.3 mm SL); Urauchi-gawa River: E (OMNH-P 40040, male, 43.6 mm SL) and F (SPMN-PI 46249, female, 46.0 mm SL); Yuchin-gawa River: G (OMNH-P 40323, male, 63.0 mm SL) and H (OMNH-P 40327, female, 49.2 mm SL). Photographed by T. Suzuki.