Hippocampus haema, Han, Sang-Yun, Kim, Jin-Koo, Kai, Yoshiaki & Senou, Hiroshi, 2017

Han, Sang-Yun, Kim, Jin-Koo, Kai, Yoshiaki & Senou, Hiroshi, 2017, Seahorses of the Hippocampuscoronatus complex: taxonomic revision, and description of Hippocampushaema, a new species from Korea and Japan (Teleostei, Syngnathidae), ZooKeys 712, pp. 113-139 : 122-124

Hippocampus haema sp. n. Figs 3A E, 4A, 5A B, 6A, 6D, Tables 2, 3

Hippocampus coronatus : Jordan and Snyder 1901: 19; Mori 1928: 5; Boeseman 1947: 195; Mitani 1956: 30; Chyung 1977: 272; Araga 1984: 89; Senou 1993: 489 (right fig.), 1294; Kim and Lee 1995: 76; Nakamura 1999b: 125; Senou 2000: 536; Choi et al. 2002: 141; Senou 2002: 536, 1508; Kim et al. 2005: 203; Choi et al. 2006; Yoshino and Senou 2008: 76; Kohno et al. 2011: 127; Senou 2013: 635, 1911; Han et al. 2014: 423 (non Temminck & Schlegel).

Hippocampus cf. coronatus : Kuiter 2009: 128.

Hippocampus sindonis : Nakamura 1999a: 124; Yoshino and Senou 2008: 76; Kim et al. 2013: 42 (non Jordan & Snyder).

Hippocampus kuda : Kim et al. 2001: 67, Myoung et al. 2002: 74 (non Bleeker).

Hippocampus sp.: Kim and Ryu 2017: 110.

Holotype.

PKU 9641, 1, female, 90.3 mm SL, Namcheon Harbor, Namcheon 1-dong, Suyeong-gu, Busan, Korea, 35°08'16"N; 129°06'51"E, 9 Aug 2013, H. J. Kwun, hand net.

Paratypes.

139 specimens: specimens (74.0 99.0 mm SL). Korea: NIBR-P 5412, 1, female, 74.0 mm SL, off Geomun Island, Yeosu-si, Jellanam-do, depth 18 m, 17 Apr 2009, T. S. Park, SCUBA Diving & hand net. NIBR-P 1602, 1, 59.4 mm SL, Wonpo, Yeosu-si, Jeollanam-do, 27 Aug 2006, J. H. Ryu. NIBR-P 19724, 3, 58.4 71.8 mm SL, 25 Jan 2012, H. G. Cho & S. H. Lee; NIBR-P 19725 19727, 19729, 7, 33.3 102.2 mm SL, 13 Sep 2012, Y. Eun, S. Lee & S. S. Hong; Jisepo-ri, Irun-myeon, Geoje-si, Gyeongsangnam-do. PKU 6097, 1, 77.5 mm SL, 30 Aug 2011; PKU 9422 9424, 3, 80.6 92.3 mm SL, 12 Jul 2013, hand net; PKU 9704, 1, 82.3 mm SL, 1 May 2013, J. M. Lee; PKU 9705 9712, 8, 65.7 98.1 mm SL, 26 Jul 2012, J. M. Lee; PKU 9713 9717, 9719 9720, 7, 61.6 85.1 mm SL, 9 Dec 2012, J. M. Lee; PKU 9721 9723, 3, 80.8 91.5 mm SL, 20 Aug 2012, J. M. Lee; PKU 9724 9731, 8, 73.2 113.9 mm SL, 17 Jul 2012, J. M. Lee; PKU 9732 9740, 9, 62.4 100.2 mm SL, 17 Aug 2012, J. M. Lee; PKU 9741 9747, 7, 56.4 81.9 mm SL, 21 Jun 2012, J. M. Lee; PKU 9748, 1, 56.8 mm SL, 11 Sep 2012, J. M. Lee; PKU 10128 10129, 2, females, 52.2 62.7 mm SL, 23 Oct 2013, H. J. Kwun; PKU 54069 54074, 6, 32.3 77.5 mm SL, 21 Mar 2015, J. M. Lee; Namcheon Harbor, Namcheon 1-dong, Suyeong-gu, Busan, 35°08'16"N; 129°06'51"E, hand net. PKU 7230 7233, 4, 41.9 83.7 mm SL, Ulsan, 14 Sep 2012, hand net. PKU 10277, 1, 72.7 mm SL, Minrak Harbor, Millak-dong, Suyeong-gu, Busan, 35°09'14"N; 129°07'51"E, 20 Feb 2014, H. J. Yu & W. J. Lee, hand net. PKU 11159, 1, 30.9 mm SL, Hak-ri, Ilgwang-myeon, Gijang-gun, Busan, 22 Jul 2014, J. Y. Bae, hand net. PKU 11170 11180, 11, 74.2 102.4 mm SL, Soan Island, Soan-myeon, Wando-gun, Jeollanam-do, May 2014, S. Rho, bottom trawl. PKU 11181 11182, 2, 71.8 84.2 mm SL, Gunhak village, Jeonil-ri, Hoecheon-myeon, Boseong-gun, Jeollanam-do, 24 Dec 2013, S. Rho, bottom trawl. PKU 11266, 1, 74.1 mm SL, 24 Jul 2014; PKU 11634, 1, 69.9 mm SL, 25 Sep 2014; Hwayang-myeon, Yeosu-si, Jeollanam-do, hand net. PKU 11395 11401, 7, 62.3 98.7 mm SL, Jangu Island, Suwol-ri, Dosan-myeon, Tongyeong-si, Gyeongsangnam-do, Sep 2014, K. S. Han & H. D. Mun, Shrimp beam trawl. PKU 11449, 1, 81.0 mm SL, Jul 2014; PKU 11635 11637, 3, 15.9 84.7 mm SL, 24 Sep 2014; Gijang-gun, Busan, hand net. Japan: RMNH.PISC.D 1541 1542 (photograph by RMNH), 2, female, 67.5 68.5? mm SL, von Siebold collection. FAKU 109359, 1, 58.0 mm SL, Tassha, Sado Island, Niigata, 24 Oct 1955. FAKU 135638, 2, 82.7 88.9 mm SL, 22 Sep 2011; FAKU 135639, 2, 53.2 86.0 mm SL, 23 Aug 2010; FAKU 135640, 135644, 2, 76.2 86.8 mm SL, 29 Jul 2011; FAKU 135641, 1, 61.4 mm SL, 20 Aug 2008; FAKU 135642, 1, 57.4 mm SL, 6 Sep 2008; Maizuru Bay, Maizuru, Kyoto, Y. Kai. FAKU 136087, 1, 76.1 mm SL, Tsuruga, Fukui, 28 Jun 2014. FAKU 136119, 1, 59.2 mm SL, Kamai, Kyotango, Kyoto, 19 Jul 2014, F. Tashiro. KPM-NI 1615, 1, 91.6 mm SL, Aug 1933. KPM-NI 6770, 1, 57.9 mm SL, Azo, Tsuruga, Fukui, depth 5 m, 13 Aug 1999, T. Nomura. KPM-NI 24769, 1, female, 83.3 mm SL, Akita, H. Sugiyama. KPM-NI 31204, 1, 47.5 mm SL, Takahama-cho, Ooi, Fukui, 2 Oct 2012, M. Mune. KPM-NI 31620, 1, 72.7 mm SL, 27 Feb 2013; KPM-NI 31707, 1, 60.6 mm SL, 11 Mar 2013; Ogurui, Takahama-cho, Ooi, Fukui, depth 7 m, M. Mune. KPM-NI 31880 31883, 4, 76.6 85.5 mm SL, depth 0 2 m, 7 May 2013; KPM-NI 36111 36112, 2, 77.1 78.6 mm SL, depth 1 3 m, 28 Apr 2014; Agurizaki Point, Ooshima, Ooi-cho, Ooi-gun, Fukui, M. Mune. KPM-NI 35122 35123, 2, 46.3 46.8 mm SL, Tanoura, Takahama, Ooi-cho, Ooi, Fukui, depth 0 1 m, 3 Jul 2013, M. Mune. KPM-NI 35291 35297, 7, 54.5 74.9 mm SL, Koda Fishing Port, Notojimakouda-machi, Notojima Island, Nanao, Ishikawa, depth 1 3 m, 2013, H. Masaki. KAUM-I 12745, 1, 100.5 mm SL, 12 Oct 2007, depth 5 m, kept in Kagoshima Aquarium and dead on 8 Dec 2008; KAUM-I 12746, 1, 96.9 mm SL, 13 Feb 2008, kept in Kagoshima Aquarium and dead on 4 Aug 2008; off Nagashima Station, Faculty of Fisheries, Kagoshima University, Usui, Azuma, Izumi, Kagoshima, M. Yamada. KAUM-I 19885, 1, male, 99.0 mm SL, off Nagashima Station, Faculty of Fisheries, Kagoshima University, Usui, Azuma, Izumi, Kagoshima, 32°13'22"N; 130°10'31"E, 13 Feb 2008, Kagoshima Aquarium, hand net, kept in Kagoshima Aquarium and dead on 30 Apr 2007.

Diagnosis.

A species of Hippocampus having a bony body; double gill openings; R 10 + 35 38, mode 10 + 36 (holotype: 10 + 36); coronet moderately high and turned back on top; CoT 4; CHGO 22.7 41.6 % HL; CHMC 34.1 54.9 % HL; a WS on the dorsal fin base.

Description.

Head and trunk folded at approximately right angle; snout elongated and fused; pelvic and caudal fins absent; prehensile tail; D 11 14, mode 13 (holotype: 14); A 4; P 10 13, mode 12 (holotype: 13); D always greater than or equal to P; CS 1; ES 1 2 (in ES 2, anterior ES smaller than posterior ES), mode 1 (holotype: 2); SnL 28.8 49.0 % HL; ED 27.1 68.9 % SnL; HL 57.3 88.7 % TrL; TrL 37.4 57.2 % TaL; often flat and smooth skin covering armor-plated body; coronet turned back on top; CoT 4 arising from degenerative PCS (5th coronet tip); WS two fused spines (lower spine more developed than upper spine, recurved; occasionally, upper spine stands out giving appearance of two dorsal fin base spines); dorsal and lateral spines at 1st, 4th, 7th, and 10thTrR more prominent than on other TrRs, except for lateral spines on 10thTrR (occasionally none or degenerative spine); Several skin filaments on body, ACS, and prominent dorsal and lateral spines on 1st, 4th, and 7thTrR; Several colors when fresh: black, white, orange, yellow, magenta, claret, brown, grey with black, red, or white stripe, and frostlike whitish or grey striations along prominent TrR and TaR; whitish radial blotches from iris to surrounding eye often present; semicircular band on dorsal fin occasionally present; when fixed in alcohol, specimens become black, white, brown, and grey; blunt (or absent) body spine; no particular sexual dimorphism except for male brood pouch. Minimum size at sexual maturity, 53.9 mm SL in males.

Distribution.

Korea: southern and southeastern coasts of the Korean Peninsula (from Soan Island to Ulsan); Japan: western coast of Kyushu (western Kagoshima Prefecture), northwestern coast of Honshu (from Kyoto Prefecture to Akita Prefecture) (Fig. 1). Lives in floating Sargassum and weeds on shallow soft bottom habitats from 0 18 m depth (e.g. Kim et al. 2016).

Etymology.

The Korean word Haema means seahorse, which connotes representative and common. Thus, the scientific and Korean names Haema were chosen to indicate that this seahorse is the one most commonly found in Korea. The Japanese name Himetatsu means princess seahorse or dwarf seahorse, and refers to its lower coronet and smaller body compared to H. coronatus .

Remarks.

Temminck and Schlegel (1850) described the extremely high coronet as follows: coronet height (CHGO, based on the inquiry of type specimens and on Jordan and Snyder [1901] s description) of H. coronatus is identical to its SnL, 1/5 shorter than remaining HL (i.e., 4/9 of HL). All H. haema specimens present a moderately high coronet (CHGO 22.7 41.6 % HL and CHMC 34.1 54.9 % HL) when compared to H. coronatus (extremely high coronet, CHGO 43.0 60.1 % HL and CHMC 55.7 79.0 % HL). Our H. sindonis specimens (including the holotype, USNM 49730) differ from H. haema in their 5 CoT and blunt or truncated LTrDS (vs. CoT 4 and WS [recurved LTrDS] in H. haema ) (Fig. 6). The genetic distance between H. haema and H. coronatus is greater than that between species of the H. kuda complex (i.e., H. kuda , H. reidi , and H. ingens ), supporting specific distinctness (Fig. 7; Table 4).

Our data also suggest the existence of two subgroups, one from Korea and another from Japan: cyt b sequences of H. haema collected in these two areas consistently present two base pairs (bp) differences (0.3% 0.8% genetic distance). Based on molecular results, H. haema is more closely related to H. coronatus than to H. sindonis (Fig. 7; Table 4), but based on coronet height and on the number of TaR, except for CoT and WS, it is more similar to H. sindonis (Tables 2 and 3).

Hippocampus haema was collected off the southern and southeastern coasts of Korea, but we were not able to collect H. haema off the western or northeastern coasts of Korea; only H. mohnikei was collected from all Korean waters. A few studies have reported H. coronatus from the western coast of Korea ( Lee and Seok 1984; Hwang 1998; Hwang et al. 1998; Hwang et al. 2005), but these publications are mostly checklists, similar to that of Mori (1928), and H. mohnikei is not referred to in written records. Such inconsistency might be the result of misidentifications. The northern boundaries of H. coronatus in Korean waters determined in our study are similar to the distributions found by Choi et al. (2002) and Kim et al. (2005), who stated H. coronatus was limited to the southern coast of Korea, similarly to H. mohnikei . We found that the habitat of H. haema is affected by the Tsushima Warm Current ( Briggs 1995; Nakabo 2009; Ishizu et al. 2017) and, therefore, H. haema might only rarely be found off the western and northeastern coasts of Korea.