A global revision of the Seahorses Hippocampus Rafinesque 1810 (Actinopterygii: Syngnathiformes): Taxonomy and biogeography with recommendations for further research
Author
Sara A. Lourie
Author
Riley A. Pollom
Author
Sarah J. Foster
text
Zootaxa
2016
4146
1
1
66
journal article
10.11646/zootaxa.4146.1.1
f27bf01d-bf27-4e86-b2ba-81b84931d348
1175-5326
268078
35E0DECB-20CE-4295-AE8E-CB3CAB226C70
H. kuda
Bleeker 1852
English common names. Spotted Seahorse
, common seahorse, estuarine seahorse, estuary seahorse, oceanic seahorse, yellow seahorse.
Synonyms.
H. aterrimus
Jordan
and Snyder 1902,
H. borboniensis
Duméril 1870
,
H. chinensis
Basilewsky 1855
,
H. fuscus
Rüppell 1838
,
H. hilonis
Jordan
and Evermann 1903
,
H. horai
Duncker 1926
,
H. melanospilos
Bleeker 1854
,
H. moluccensis
Bleeker 1852
,
H. novaehebudorum
Fowler 1944
,
H. polytaenia
Bleeker 1854
,
H. raji
Whitley 1955
(=
H. kuda multiannularis
Raj 1941
),
H. rhynchomacer
Duméril 1870
,
H. taeniops
Fowler 1904
,
H. taeniopterus
Bleeker 1852
,
H. tristis
Castelnau 1872
Syntypes.
(2) RMNH 5167 (1 of several), BMNH 1867.11.28.360 (see also Bleeker specimens: NMV 46227- 28 (2)).
FIGURE 25.
Range map for
Hippocampus kuda
.
See Figure 2 caption for further details.
Type
locality.
Singapore
Distribution.
Australia
(northern),
Bahrain
,
Cambodia
,
China
(including
Hong Kong
SAR and Province of
Taiwan
)
,
Comoros
,
Cyprus
,
Djibouti
,
Egypt
,
Eritrea
,
Fiji
,
France
(
Réunion
),
India
,
Indonesia
,
Iran
,
Israel
,
Japan
,
Kenya
,
Kuwait
,
Lebanon
,
Malaysia
,
Madagascar
,
Mauritius
,
Mozambique
,
Federated States of Micronesia
,
New Caledonia
,
Oman
,
Pakistan
,
Papua
New Guinea
,
Philippines
,
Qatar
,
Saudi Arabia
,
Seychelles
,
Singapore
,
Solomon Islands
,
Somalia
,
South
Africa
(eastern),
Sri
Lanka
,
Sudan
,
Syria
,
Tanzania
,
Thailand
,
Tonga
,
Turkey
,
United Arab Emirates
,
USA
(
Hawaii
),
Viet Nam
.
Notes.
Hippocampus kuda
is a very widespread species (or species-complex) that exhibits localized haplotypes, phylogeographic structuring (Lourie 2004;
Teske
et al.
2005
), and variable morphology. BOLD (2016) separates the 54 sequenced specimens into four BINS (Barcorde Identification Numbers) although they only differ from one another by 1.28–2.25% (648 bp, CO1), and two of the three BINS with more than a single specimen contain members of more than one purported species. Furthermore, overlapping meristics, paraphyly among purported species, genotypes from different clades (BINS) in the same populations, and lack of diagnostic morphological differences mean that, pending further research, we are unable to uphold purported species as valid in this revision. The global ‘
H. kuda
-clade’ includes
H. kuda
,
H. fuscus
,
H. borboniensis
,
H. capensis
,
H. algiricus
, and
H. reidi
(
Casey
et al.
2004
;
Silveira
et al.
2014
;
Teske
et al.
2005
; BOLD 2016). We have here synonymized
H. fuscus
and
H. borboniensis
due to a lack of distinguishable morphological, genetic, or geographic differences from
H. kuda
proper (from Southeast Asia). Note that this implies that
H. kuda
is in fact a Lessepsian migrant, meaning that it has passed through the
Suez
Canal and into the Mediterranean Sea (
Golani & Fine 2002
). We retain
H. reidi
and
H. algiricus
based on their subtly distinctive coronets, longer snouts, but mostly their large geographic separation (see Discussion). Further studies are needed to determine whether gene flow occurs across the Atlantic, as these two species appear to be very close genetically (1.3% divergence in 1141bp,
cytb,
according to
Casey
et al
. 2004
and 1.6% divergence in 652bp, CO1, according to
Silveira
et al.
2014
). We also conservatively retain
H. capensis
based on its distinctive coronet, noticeably and consistently smaller size, ecological considerations (it appears to be one of the most brackish-water tolerant seahorses and has only been found in estuaries—Lockyear
et al.
2006), and conservation status (it is the only seahorse listed as Endangered on the IUCN Red List—Czembor &
Bell 2012
). Comparisons of cyt
b
sequences of present-day specimens identified as
H. kuda
from
Hawaii
with the
type
specimen of
H. hilonis
revealed the same unique haplotype and led the authors to classify them as a subspecies
H. kuda hilonis
(
Szabó
et al.
2011
)
. That said, the Hawaiian haplotype differs from Taiwanese and
Philippines
haplotypes by only one and two bases, respectively. Thus we do not support the acceptance of subspecific classification. The synonymization of
H. melanospilos
and
H. taeniopterus
with
H. kuda
was likely Bleeker’s own (according to manuscript notes to complete Bleeker’s Atlas of Ichthyology by
Popta 1895
).
Lourie
et al.
(1999)
followed Popta’s synonymy and we do here as well. According to Kuiter (2009), the
type
specimens of
H. moluccensis
are housed at the Museum of
Victoria
, although this identification is tentative. Kuiter further identifies them as a spiny species, however after examination of a photograph of one of the specimens we conclude that it is not spiny and more strongly conforms to
H. kuda
(SL
pers. obs.
). The
type
description of
H. moluccensis
also repeatedly mentions ‘low tubercles’ and nothing about spines. The original description of
H. tristis
only mentions a single specimen (
Castelnau 1872
), however there are two
type
specimens in MNHN. Castelnau’s paper chiefly deals with fish from the Melbourne fish market and he gives no indication as to the origin of the specimens. The specimen labels however, suggest they are from ‘Swan
River
, Australia’. Both Melbourne and Swan
River
are outside the range of
H. kuda
and it is possible that the specimens came from elsewhere. Morphologically they conform to
H. kuda
.
Other names that we synonymise, based on our examination of the
type
material, morphologically conform to
H. kuda
(e.g.
H. aterrimus
,
H. novaehebudorum
,
H. polytaenia
—see also notes under
H. spinosissimus
,
H. rhynchomacer
,
H. taeniops
) (Appendix I). Remaining names lack
type
specimens, or we were unable to examine the
types
, and are synonymised based on the original morphological descriptions (e.g.
H. chinensis
,
H. horai
,
H. raji
and
H. taeniopterus
).