F. L. de Castelnau’s Norman River fishes housed in the Macleay Museum, University of Sydney
Author
Gill, Anthony C.
Author
Russell, Barry C.
Author
Nelson, Gary
text
Zootaxa
2018
2018-08-16
4459
3
565
574
journal article
29008
10.11646/zootaxa.4459.3.9
ad9c1f20-5e3c-400f-9ca8-7a8c46347063
1175-5326
1458925
79B91BA4-C861-4EA1-85D9-7AE039D950B4
Engraulis nasutus
Castelnau 1878
[=
Thryssa nasuta
]
Figures 6–7
Engraulis nasutus
Castelnau 1878b
: 51
(
type
locality,
Norman River
).
Castelnau (1878b)
described
Engraulis nasutus
on the basis of an unspecified number of specimens from the Norman River. He noted that “I have seen only one adult specimen seven inches long, but I have a small specimen preserved in spirits, which is silvery with the upper parts of a light brown, fins yellow”. This suggests he had at least two specimens.
Identification of the species has been problematic. Macleay (1879) considered it to be a valid species of
Engraulis
, stating (p. 367): “This species is described by Count Castelnau […] from one adult specimen,
7 inches
long, sent to him from the Norman River, Gulf of Carpentaria. Its special distinguishing character seems to be a strong longitudinal ridge along the top of the head.” Macleay’s mention of a single specimen is curious, given that there are two specimens in
MAMU
(see below).
Ogilby (1910)
considered
E. nasutus
to be a valid species of
Anchovia
Jordan
& Evermann in
Jordan
(1895)
, and compared it with his new species
A. aesturia
. It is unlikely that Ogilby saw
type
material of
E. nasutus
, as all of his comparative data for the species is identical to that in Castelnau’s original description.
McCulloch (1929a)
regarded
E. nasutus
as a valid species of
Anchoviella
Fowler (1911)
, but did not indicate whether he had examined the
syntypes
. Whitley (1964) considered both
E. nasutus
and
A. aestuaria
to be valid species of
Thrissina
Jordan
& Seale (1925)
. Whitehead
et al.
(1988) tentatively placed
E. nasutus
in the synonymy of
Thryssa hamiltoni
(
Gray 1835
)
, which was followed also by Wongratana
et al.
(1999). Paxton
et al.
(2006) listed it as
incertae sedis
in the
Engraulidae
, and as a possible synonym of
Thryssa hamiltoni
.
They noted (p. 317): “
syntypes
whereabouts unknown.”
There are two specimens in the Macleay Museum (
MAMU
F.1194;
Figures 6–7
), measuring 99.5 and
104.5 mm
SL (TL not determinable owing to caudal-fin damage). They correspond to an index card stating “
Engraulis nasutus
, Cast.
[…]
2 sp.
6″ Norman R., N.
Australia
”. The specimens have the following characters (where two counts are presented, the first is from the
99.5 mm
SL specimen): predorsal scutes 1; abdominal scutes sharply keeled, 14 prepelvic + 9 postpelvic = 23 total; maxilla relatively short, reaching to posterior border of preopercle; anal-fin rays 34 (iv,30; anterior ray tips damaged in
104.5 mm
SL specimen); total dorsal-fin rays 13; uppermost pectoral-fin ray not filamentous; teeth in jaws fine and conical, not canine-like; lower gill rakers 25 (checked in
104.5 mm
SL specimen only). This combination of characters is unique among engraulids to the species currently called
Thryssa aestuaria
(
Ogilby 1910
)
. According to Paxton
et al.
(2006), there are three other species of
Thryssa
known from the Gulf of Carpentaria:
T. hamiltoni
,
T. scratchleyi
(
Ramsay & Ogilby 1886
)
and
T. setirostris
(
Broussonet 1782
)
. The
MAMU
specimens differ from
T. hamiltoni
in having fewer prepelvic scutes (14 vs 15–20) and more lower gill rakers (25 vs 11–15); from
T. scratchleyi
in having fewer abdominal scutes (14 prepelvic + 9 postpelvic vs 19 + 12) and more lower gill rakers (
18–23 in
T. scratchleyi
); and from
T. setirostris
in having a much shorter maxilla (reaching to preopercle edge vs to at least tip of pectoral fins), fewer abdominal scutes (16–18 + 9– 10 =
25–28 in
T. setirostris
) and more lower gill rakers (
10–12 in
T. setirostris
).
We regard the specimens in MAMU F.1194 as syntypes of
Engraulis nasutus
Castelnau, 1878
, and identical to
Anchovia aestuaria
Ogilby, 1910
.
Engraulis nasutus
thus is a subjective senior synonym of
A. aestuaria
. We here follow Eschmeyer
et al.
(2018, and references therein) in recognising
Thryssa
Cuvier (1829)
rather than
Thrissina
Jordan & Seale (1925)
(
Kottelat 2013
) as the correct generic name for
Thryssa nasutus
.
Pusey
et al.
(2017)
recorded only a single engraulid from freshwaters of northern Australia,
Thryssa scratchleyi
.
Thryssa nasuta
is known only from estuarine and marine areas (Whitehead
et al.
1988, Wongratana
et al.
1999); presumably the syntypes of
E. nasutus
were collected from the lower, estuarine reaches of the Norman River.