A review of the flying fish genus Cypselurus (Beloniformes: Exocoetidae). Part 2. Revision of the subgenus Poecilocypselurus Bruun, 1935 with descriptions of three new species and five new subspecies and reinstatement of Exocoetus apus Valenciennes and E. neglectus Bleeker
Author
Shakhovskoy, Ilia B.
ilisha@yandex.com
Author
Parin, Nikolay V.
text
Zootaxa
2022
2022-03-23
5117
1
1
109
http://dx.doi.org/10.11646/zootaxa.5117.1.1
journal article
94527
10.11646/zootaxa.5117.1.1
4d31b234-af7e-403f-bc87-f7101f082487
1175-5326
6378619
CFA7895B-43A7-4E19-8623-E8EAE4C43A89
Cypselurus neglectus neglectus
(
Bleeker, 1865
)
Material examined.
Seventy-one specimens
24–160.5 mm
SL.
Tonkin
Bay.
Full morphological study.
IORAS 04007
(
1, 160.5 mm
SL),
Tonkin Bay
,
22.04.1960
.
IORAS 04008
(
1, 154 mm
SL),
Tonkin Bay
.
IORAS 04009
(
1, 157 mm
SL),
Tonkin Bay
.
IORAS 04010
(
1, 147 mm
SL),
20°20’N
108°46’E
,
7.07.1961
.
IORAS 04011
(
1, 152 mm
SL),
Tonkin Bay
.
IORAS 04012
(2, 128–
160.5 mm
SL),
Tonkin Bay
.
IORAS 04013
(6, 83–
117 mm
SL),
20°00’N
107°40’E
,
12.08.1961
.
IORAS 04014
(3, 145–
152 mm
SL),
Tonkin Bay
.
IORAS 04015
(
1, 149 mm
SL),
Tonkin Bay
,
6.08.1961
.
IORAS 04016
(2, 112–
152 mm
SL),
Tonkin Bay
.
IORAS 04017
(2, 113–
145 mm
SL),
19°00’N
106°30’E
,
13.08.1961
.
IORAS 04018
(
1, 149 mm
SL),
Tonkin Bay
.
Partial morphological study.
IORAS 04018
(1, 64 mm SL),
Tonkin
Bay
.
IORAS 04019
(1, ~
24 mm
SL),
20°20’N
108°46’E
,
7.07.1961
.
IORAS
uncat.* (2, 74–
135 mm
SL),
20°10’N
108°47’E
,
14.08.1961
.
Other areas.
Full morphological study.
IORAS 04020
(
1, 157 mm
SL),
Danang
,
Vietnam
,
18.04.1980
.
IORAS 04021
(
1, 143.5 mm
SL),
Singapore
.
IORAS 04022
(
1, 147 mm
SL),
2°04’N
106°15’E
,
6.03.1975
.
IORAS 04023
(1, 39 mm SL),
1°58’N
105°53’E
,
13.07.1971
.
IORAS 04024
(1,
33.5 mm
SL),
3°04’N
109°28’E
,
13.06.1971
.
IORAS 04025
(
1, 133 mm
SL),
1°58’N
105°53’E
,
13.06.1971
.
IORAS 04026
(
1, 141 mm
SL),
2°09’N
106°09’E
, 6-
7.03.1975
.
IORAS 04027
(
1, 109 mm
SL), 0°00’ 135°10’E,
3.04.1966
.
IORAS 04028
(2, 37–
52 mm
SL),
Kieta Harbour
,
Bougainville
, 9-
10.01.1966
.
IORAS 04029
(2, 35–47.5),
Surabaya
, 13–
15.10.1959
.
AMS
uncat. (2, 33–
34 mm
SL),
Sek Harbour
,
21.09.1971
.
AMS
uncat. (1, 43 mm SL),
Madang
,
11.08.1971
.
CAS
81124* (
1, 137.5 mm
SL),
12°33’N
101°16’E
,
27.10.1957
.
CAS
81190 (1, 83 mm SL),
10°02’N
109°48’E
,
24.09.1960
.
FRSKU 44256
(
1, 135 mm
SL),
Gulf
of
Thailand
,
30.10.1970
.
SIO 61-634
(1, 65 mm SL),
12°04’N
101°59’E
,
11.02.1961
.
SOSC
Ref.No.
190 (9, 125–149),
6°30’N
118°45’E
,
27.01.1965
.
SIO 65-40
(
1, 142 mm
SL),
Gulf
of
Thailand
.
ZMUC
P341008
(
1, 148 mm
SL),
9°59’N
107°23’E
,
11.04.1929
.
ZMUC
uncat (
1, 142 mm
SL),
4°25’S
160°00’E
, 6-
7.10.1951
.
ZMUC
uncat. (
1, 156 mm
SL),
7°00’N
103°18’E
,
8.06.1951
.
Partial morphological study.
IORAS 04030
(1, 74 mm SL),
7°44’S
120°05’E
,
15.03.1975
.
IORAS
uncat.* (
1, 143 mm
SL),
2°05’N
106°12’E
,
6.08.1975
.
AMS
I.16747-010* (1, 50 mm SL),
Madang
Harbour
,
PNG
,
30.09.1969
.
CAS
81114* (
1, 129 mm
SL),
9°N
103°E
,
22.08.1959
.
CAS
81119* (
1, 141 mm
SL),
5°59’N
105°23’E
,
23.06.1960
.
CSIRO
C.3096* (
1, 145 mm
SL),
Möwe Harbour
,
New Britain
,
2.01.1949
.
HUMZ 90194
* (
1, 160 mm
SL), no data
.
ISH 5-1993
* (
1, 100 mm
SL), off
Chumpon
, Gulf of
Thailand
,
6.12.1993
.
Institute of Marine Research
(
Vietnam
)
No.
51789* (
1, 117 mm
SL),
Can Bong
,
1.08.1976
.
USNM 135803
*
#
(
1, 132.5 mm
SL),
Catbalogan
,
Samar I.
,
15.04.1908
.
Type
material.
BMNH
1866.5.2.34* (
1, 165 mm
SL), no data.
RMNH 6975
* (2, 143–
187 mm
SL), no data
.
Description.
Meristic and morphometric characters are given in
Tables 1–5
and
9–10.
D
10
–13 (usually 11–12),
A
7–9 (usually 8),
P
I 13–15 (usually I 14),
Spred
23–29 (usually 25–28),
Str
8–9½ (usually 8½),
Sp.br
21–25 (5–8 + 15–19), usually 22–24 (6–7 + 16–17),
Vert
40–42 (25–28 + 14–17), usually 41 (26–27 + 14–15). Snout short (
Figs. 23
,
25
), lower jaw shorter than upper or of equal size (rarely lower jaw slightly longer). Upper jaw not pointed anteriorly. Jaw teeth small to medium-sized (not visible or barely visible to the naked eye), mainly tricuspid and (or) with additional cusps (some specimens also have conical teeth). Juveniles <
80 mm
have mainly conical teeth. Teeth arranged in 2–5 rows, in juveniles in 1–3 rows. Palatine teeth always present, usually numerous (sparse in juveniles <
40 mm
SL).
Body elongate (
Figs. 23
,
25
), greatest body depth changing slightly with growth: in juveniles
33–100 mm
SL body depth
5.15–5.9 in
SL and in fish
110–160 mm
SL,
4.55–5.7 in
SL. Body width 0.97–1.40 and caudal peduncle depth
2.01–2.81 in
greatest body depth. Greatest head depth and head length not changing with growth, 5.1–6.0 and
3.8–4.4 in
SL, respectively. Head length
0.95–1.22 in
dorso-caudal distance. Eyes large, eye diameter decreasing strongly with growth (
Fig. 26a
): in juveniles
33–100 mm
SL eye diameter
8.55–11.8 in
SL,
2.05–2.9 in
head length,
0.95–1.4 in
interorbital width and
0.85–1.3 in
postorbital distance; in fish
110–160 mm
SL,
10.6–14.3 in
SL,
2.75–3.35 in
с
, 1.0–1.3 times in
io
and
1.15–1.5 in
po
.
Pectoral fins relatively long, their length increasing with growth to about
100 mm
SL, and afterwards nearly constant: in juveniles
33–100 mm
SL pectoral fin
1.50–1.85 in
SL; in fish
110–160 mm
SL,
1.4–1.6 in
SL. Tip of pectoral fin reaching from posterior half of dorsal-fin base to middle of caudal peduncle; in juveniles <
80 mm
SL from origin to middle of dorsal-fin base. First pectoral-fin ray unbranched, its length increasing with growth: in juveniles
33–100 mm
SL it fits
2.65–3.30 in
SL and
1.55–1.87 in
lP
; in fish
110–160 mm
SL,
2.3–2.9 in
SL and
1.53–1.85 in
lP
. Pelvic-fin base closer to posterior edge of head than to origin of caudal-fin lower lobe (
cV
/
pV
= 0.71–0.91); pelvic fins shifted slightly posteriorly as fish grows (
Fig. 26e
). Pelvic-fin length decreasing strongly from juveniles to adults (
Fig. 26c
): in juveniles
33–100 mm
SL pelvic fin
2.3–2.8 in
SL and
1.30–1.72 in
lP
; in fish
110–160 mm
SL,
2.7–3.5 in
SL and
1.74–2.21 in
lP
. Tip of pelvic fin of small juveniles
30–95 mm
SL reaching (nearly reaching) origin of caudal-fin lower lobe or slightly beyond; in juveniles
95–135 mm
SL reaching from end of anal-fin base to middle of caudal peduncle; in fish>
135 mm
SL reaching from 1
st
–3
rd
posterior anal-fin ray to slightly beyond anal-fin base.
Anal-fin origin far behind dorsal-fin origin, 1st anal-fin ray beneath 4
th
–7
th
dorsal-fin ray (usually beneath 5
th
–6
th
). Dorsal fin with 2–5 rays more than anal fin. Height of dorsal and anal fins decreasing with growth (
Fig. 26d
): in juveniles
33–100 mm
SL,
HD
8.1–8.2 and
HA
8.8–12.0 in SL; in fish
110–160 mm
SL,
HD
7.95–11.2 and
HA
11.2–14.9 in
SL. The 2
nd
or 3
rd
ray in dorsal and anal fins longest. Tip of last dorsal-fin ray reaching from middle of caudal peduncle to origin of caudal-fin upper lobe (rarely slightly further). Middle and posterior rays of dorsal fin not elongate, penultimate rays not protruding beyond tip of last ray (occasionally slightly protruding in juveniles).
FIGURE 25.
Cypselurus neglectus neglectus
: (A)—33.5 mm SL, IORAS 04024, 3°04’N 109°28’E; (B)—47.5 mm SL, IO- RAS 04029, Surabaya; (C)—65 mm SL, SIO 61-634, 12°04’N 101°59’E; (D)—83 mm SL, CAS 81190, 10°02’N 109°48’E; (E)—128 mm SL, IORAS 04012, Tonkin Bay; (F)—149 mm SL, SOSC Ref.No.190, 6°30’N 118°45’E.
FIGURE 26.
Size variation of morphometric characters (in % SL) in
Cypselurus neglectus neglectus
(+—Tonkin Bay, x—other areas) and
C. n. shcherbachevi
(□—Indonesia, ○—Andaman Sea, ∆—Bay of Bengal and Arabian Sea): (A)—eye diameter (
o
); (B)—snout length (
ao
), (C)—pelvic fin length (
lV
); (D)—dorsal fin height (
HD
); (E)—cephalo-ventral distance divided by postventral distance (index
cV/pV
); (F)—pelvic fin length divided by snout length (index
lV/ao
).
FIGURE 27.
Pectoral (A–C) and pelvic (D–F) fins in
Cypselurus neglectus neglectus
: (A)—37 mm SL, IORAS 04028, Kieta Harbour, Bougainville; (B)—65 mm SL, SIO 61-634, 12°04’N 101°59’E; (C)—133 mm SL, IORAS 04025, 1°58’N 105°53’E; (D)—37 mm SL, IORAS 04028, Kieta Harbour, Bougainville; (E)—83 mm SL, CAS 81190, 10°02’N 109°48’E; (F)—126 mm SL, SOSC Ref.No.190, 6°30’N 118°45’E.
Pigmentation.
Body of juveniles (
Fig. 25a–d
) pale brown to dark brown, the ventral side usually darker than dorsal. Body bands usually absent (juveniles occasionally with 1–2 indistinct dark bands posteriorly). Adults with typical “pelagic” pigmentation.
Lower surface of head in juveniles
33–55 mm
SL brown to dark brown with paler chin and distal parts of branchiostegal rays (in a single juvenile
39 mm
SL rather pale with wide dark band under eyes). In fish>
60 mm
SL, lower surface of head mainly pale; in juveniles
60–110 mm
SL usually with weak aggregation of melanophores under eyes (on bases of branchiostegal rays). Adults with a few small dark specks (
Fig. 25f
) on gill covers and (or) under eyes.
Pectoral fins in juveniles
24–80 mm
SL (
Fig. 27a–b
) brown or dark brown with pale tip (sometimes also with small pale spots near tips of 2
nd
and 3
rd
rays); without pale transverse band or a row of pale spots. In fish
80–115 mm
SL, pigmentation disappearing at lower edge of the fin (below 9–12
th
ray). In fish>
115 mm
SL (
Figs. 23a
,
27c
), pectoral fins dark gray to dark brown to 8
th
ray (rarely to 7
th
or 9
th
) with broad pale tip and very narrow posterior pale edging; distally pectoral-fin pigmentation usually spreading one ray lower than proximally.
Pelvic fins in juveniles
24–80 mm
SL (
Fig. 27d–e
) entirely brown or dark brown. In fish
80–100 mm
SL, pigmentation begins to disappear starting with proximal part of the fin, along 1
st
ray and between 5
th
–6
th
rays. In fish
100–120 mm
SL, pelvic fins pale with a large dark spot between 2
nd
–4
th
rays distally. In fish ≥
120 mm
SL, pelvic fins pale (
Figs. 23a
,
27f
), occasionally with few dots or a dark streak between some rays.
Dorsal fin in juveniles
33–80 mm
SL covered with melanophores, more densely near bases of anterior rays and along upper margin of fin; posterior edge devoid of pigmentation. In fish
80–115 mm
SL dorsal fin pale brownish with darker upper margin. In fish>
115 mm
SL, dorsal fin gray, sometimes with yellowish or brownish tinge near fin base.
Anal fin in juveniles
33–85 mm
SL covered with melanophores, mainly near fin base anteriorly and on posterior part of fin (sometimes aggregated there in a brown spot, see
Fig. 23b
). In fish
85–90 mm
SL
(
65 mm
SL from
Tonkin
Bay) anal fin pale with weak pigmentation near tips of posterior rays. In fish>
110 mm
SL, anal fin pale or translucent.
Caudal fin of fish
33–45 mm
SL (
Fig. 25a
) pale, with pale brown to brown base and dots along lower lobe rays (except uppermost rays). In fish
45–100 mm
SL (
Figs. 23b
,
25b–d
), caudal fin usually with 1–3 dark bands on lower lobe and, in some fish, also with 1–2 bands on upper lobe. In fish>
100 mm
SL, caudal fin gray to brown, usually with darker fin base and distal part of upper lobe (
Fig. 25e–f
).
Coloration in life
. No data.
Maximum size.
The maximum length of
C. n.
neglectus
in our material was
160.5 mm
SL (IORAS 04007,
Tonkin
Bay, female). The largest male was
157 mm
SL.
Intrasubspecies variation.
Fish from
Tonkin
Bay differ slightly from others in having more predorsal scales (usually 26–29 vs. usually 26–27), a smaller interorbital space (see
Table 9
) and paler pigmentation of anal fin in juveniles (the fin is mainly pale starting with
65 mm
SL vs.
85 mm
SL). We regard these differences to have no taxonomic significance.
Common names.
The name “common neglected flying fish” (Russian: “обыкновенный ПриЗрачный стрижехвост”) is proposed here.
Biology.
Males mature at
133 mm
SL, females at
141 mm
SL. Close to mature or mature fish were captured near
Singapore
in March (IORAS 04026) and June (IORAS 04025), in Gulf of
Thailand
in June (ZMUC uncat.), in
Tonkin
Bay in April (IORAS 04007) and August (IORAS 04015). The smallest juveniles,
24–35 mm
SL, were captured east of
Singapore
in June (IORAS 04024), at Surabaya in October (IORAS 04029), in
Tonkin
Bay in July (IORAS 04019), in Sek Harbour in September (AMS uncat.). These data suggest
C. n.
neglectus
spawns at least from March to August-September.
Distribution.
The subspecies is distributed (
Fig. 28
) from
Singapore
(IORAS 04021), Gulf of
Thailand
(ISH 5- 1993, off
Chumpon
) and
Tonkin
Bay (IORAS 04010,
20°20’N
108°46’E
), through
Indonesia
(southernmost occurrences at Surabaya (IORAS 04029) and
7°44’S
120°05’E
(IORAS 04030)),
Philippines
and New
Guinea
eastward to Melanesia (ZMUC uncat.,
4°25’S
160°00’E
).