Revision of the South American freshwater fish genus Laemolyta Cope, 1872 (Ostariophysi: Characiformes: Anostomidae)
Author
Mautari, Kelly Cristina
Author
Menezes, Naércio Aquino
text
Neotropical Ichthyology
2006
2006-03-31
4
1
27
44
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000100002&lng=en&tlng=en
journal article
10.1590/S1679-62252006000100002
1982-0224
5418442
22071950-40B5-4151-AB3C-D6AE6A2607E9
Laemolyta garmani
(
Borodin, 1931
)
Fig. 12
Anostomus
(
Schizodontopsis
)
garmani
Borodin, 1931: 47–48
[original description,
type
locality:
Jutahy
(
Jutaí
),
Içá
,
Lake Hyavary
(
Lago Javarí
)].
Laemolyta garmani
:
Myers, 1950: 197
[diagnosis,
type
locality];
Fowler, 1950: 208
[synonymy, distribution];
Géry, 1974: 152–153
, 159 [description and identification key]; Ortega & Vari 1986: 12 [catalogue]; Garavello & Britski, 2003: 73 [catalog].
Laemolyta taeniata garmani
:
Géry, 1964: 466
[identification key].
Laemolyta garmani macra
Géry, 1974: 153–154
, fig. (2), p. 154 [original description,
type
locality: rio Nacuray, identification key];
Weber, 1998: 8
[catalog of fishes];
Eschmeyer, 1998: 963
[catalog]; Garavello & Britski, 2003: 73 [catalog].
Anostomus
(
Laemolyta
)
garmani
:
Géry, 1977: 179
[identification key, distribution].
Anostomus garmani
: Vari & Howe, 1991:5
. [
Paratype
, catalog];
Eschmeyer, 1998: 631
[catalog].
Material examined
:
50 specimens
(
39.8–214.6 mm
SL).
Brazil
.
Amazonas
:
Silva
, lago
Saracá
(
Lake Saracá
at
Silves
),
02°53’S
,
58°21’W
,
December 1865
,
Thayer S.
V
.
R
,
MCZ
19370
,
holotype
,
160.6 mm
SL.
Rio Hyutahy
,
rio Jutahy
[
rio Jutaí
, tributary of
rio Solimões
),
02°43’S
,
66°57’W
,
September 1865
,
W. James
, S.
V
.
R
.
Thayer
& “Talismã”,
MCZ
19346
,
7
out of
14 paratypes
, 78.4– 95.0 mm SL.
Rio Içá
,
rio Putomajo
[rio Içá, tributary of rio Solimões, near Brazilian-Colombian border],
03°07’S
,
67°58’W
,
MCZ
19366
,
3
out of
5 paratypes
,
63.6–72.9 mm
SL.
Rio Hyavary
,
rio Javary
[rio Javarí, tributary of rio Solimões, at Peruvian Brazilian border],
04°21’S
,
70°02’W
,
19 October 1865
,
Bourget, D
,
MCZ
32099
,
1
out of
2 paratypes
,
116.7 mm
SL.
Silva
, lago
Saracá
[Lago Saracá at Silves], (
02°53’S
,
58°21’W
),
December 1865
,
Thayer, S.
V
.
R
MCZ
94491
,
1 paratype
,
163.7 mm
SL.
Lago do Castanho
,
INPA 10823
,
1, 126.2 mm
SL.
Janauacá
,
rio Solimões
,
INPA 15210
,
1
,
75.3 mm
SL.
Janauacá
,
rio Solimões
,
INPA 10876
,
1, 213 mm
SL.
Rio Tefé
,
Ressaca de Paula
,
Tefé
,
MZUSP 32402
,
14
,
159.9
–
214.6 mm
SL.
Igarapé Baré
, lago
Amaná
, mouth of
rio Japurá
,
MZUSP 36070
,
1, 151.8 mm
SL.
Igarapé Urumutum
, mouth of
rio Japurá
,
MZUSP 36072
,
1, 178.1 mm
SL.
Rio Tefé
, lago
Tefé
,
MZUSP 61643
,
1, 195 mm
SL.
Rio Tefé
, lago
Mucura
,
MZUSP 61814
,
1
,
78.6 mm
SL.
Lago Manacapuru
,
rio Solimões
,
MZUSP 63614
,
1, 188.3 mm
SL.
Barra
do
rio Negro
,
NMW
56988
:
2,
1, 164.7 mm
SL.
Pará
: lago
Maria Preta
,
rio Capim
,
MZUSP 63828
,
1
,
39.8 mm
SL.
Mato Grosso
:
rio Aripuanã
,
ilha do Castanhal
,
INPA 24727
,
1, 168.8 mm
SL.
Rondônia
:
Forte
Príncipe
da Beira
,
rio Madeira
,
MZUSP 21381
,
1
,
50.4 mm
SL.
Goiás
:
rio Araguaia
,
Xambioá
,
INPA 1601
,
1, 142.3 mm
SL.
Ecuador
.
Napo
:
río Yasuni
, laguna
Jatuncocha
FMNH 102132
,
1
,
77.9 mm
SL.
Peru
.
Concordia
:
río Marañon
, tributary of
río Nacuary
(open water),
MHNG 2197.38
,
1
,
71.1 mm
SL, 59 (type material of
Laemolyta garmani macra
).
Departamento
Loreto
,
Quebrada
de
río Yanayacu
W of Miraflores
(
río Marañon
),
ANSP 165049
,
1
,
67.9 mm
SL.
Departamento
Loreto
,
Provincia Maynas
,
Iquitos
,
Moronacocha
,
MZUSP 26333
,
5
,
44.5–82 mm
SL.
Loreto
,
río Nanay
, about
20 km
above mouth, main channel, lateral channels and lateral ponds,
USNM 383198
,
1
,
70.2 mm
SL.
Diagnosis
.
Laemolyta garmani
is the only species in the genus with 4 longitudinal scale rows above the lateral line. Its color pattern is very similar to that of
L
.
taeniata
and
L
.
orinocensis
,
but the dark longitudinal midlateral stripe and the narrow longitudinal light stripes above the lateral line are less conspicuous in
L
.
garmani
whereas
L
.
orinocensis
has more lateral line scales (40–44
vs.
47–52).
Fig. 12.
Laemolyta garmani
, holotype, MCZ 19370, 160.6 mm SL; Brazil, Amazonas, Silva, lago Saracá. Caudal fin entirely damaged and lacking in the holotype.
Description
. Morphometric and meristic data are presented in
Table 3
. Body moderately large (SL =
39.8-214.6 mm
). Dorsal profile of body straight, posterodorsally-aligned from tip of snout to end of supraoccipital spine, straight and rising from this point to dorsal-fin origin, straight and posteroventrally-aligned from that point to caudal peduncle. Ventral profile of body approximately straight and posteroventrally-aligned from tip of lower jaw to near isthmus, slightly convex from that point to anal-fin origin. Dorsal limb gill rakers on first gill arch 9-11, 12-14 on ventral limb.
Fig. 14.
Laemolyta garmani
named “
Laemolyta garmani macra
”, MHNG
2197.38, 71.1 mm SL; Peru, río Marañon, Concordia, tributary of río Nucuray. Caudal fin damaged.
Scales large, 40-44 (42*, usually 43,
Table 2
) perforated on all of lateral line. Longitudinal scale rows from lateral line to dorsal-fin origin 4; scales rows from lateral line to anal-fin origin 4. Predorsal scales 10-13 (10*, usually 11), scales regularly arranged in most specimens. Scales rows around caudal peduncle 15-16 (15*, usually 16).
Dorsal-fin rays i or ii,10-12 (10*, usually 11); distal margin of fin slightly rounded. Anal fin short and slightly falcate, with i-ii,8-9 (8*, usually 8) rays. Pectoral fin rays i,10-14 (12*, usually 14). Pelvic fin rays i,8; distal margin of fin truncate. Vertebrae 40 (N=3).
Color in alcohol
. Upper part of body dark with dark coloration extending ventrally to about 1.5 longitudinal scale rows above lateral line. Conspicuous dark, midlateral, longitudinal stripe covering 1 to 1.5 longitudinal scale rows and extending from tip of snout to rear of caudal peduncle; stripe sometimes wider in opercular region and narrower in snout region and near to caudal peduncle. Scales above lateral line with central posterior region lighter and forming narrow light stripes or linear pattern of light dots along body.
Dorsal, pectoral, pelvic and caudal fins hyaline. Anal and adipose fins with scattered dark chromatophores.
Distribution
. Amazon basin (
Fig. 13
).
Remarks
.
Borodin (1931)
described
Laemolyta garmani
and considered it to be very similar to
L. taeniata
, but distinguished his species by having larger and fewer scales and by the presence of a darker longitudinal stripe, fins, and scales. He also mentioned that the longitudinal dark stripe extends onto the middle caudal-fin rays and is clearly visible in preserved specimens even after 64 years. These characteristics and the presence of dark chromatophores on the fins and scales although less evident, are also present in
L. taeniata
, and, thus, are not useful to distinguish the two species. The two nominal species, however, can be separated primarily on the basis of scale size and consequently scale counts.
Laemolyta garmani
was originally considered by
Géry (1964)
to be a subspecies of
L. taeniata
but later that author (1974) raised it to the species level and at the same time described a new subspecies,
Laemolyta garmani macra
based on a small sample of young specimens that had a shallower body. The
holotype
of this subspecies was not examined but M. Toledo-Piza (DZ-IBUSP) made counts and measurements on the specimen and a photo (
Fig. 14
) was provided by C. Weber (MNHG).
Figure 15
demonstrates that the body depth of the
holotype
of
Laemolyta garmani macra
does not differ significantly when compared to all the examined specimens of
L. garmani
. Although body depth varies to a certain extent among the specimens, there is no statistical difference to justify recognition of a subspecies.
Fig. 13.
Geographic distribution of
Laemolyta proxima
(black dots; open circle = type-locality),
Laemolyta garmani
(black squares; open squares = type-locality), and
Laemolyta orinocensis
(black triangles; open triangle = type-locality). Some symbols might correspond to more than one locality.
Fig. 15.
Scatter plot of body depth on standard length for specimens and holotypes
Laemolyta garmani
.
Table 2.
Frequency distribution of lateral line scales in
Laemolyta
.
Lateral line scales |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
47 |
48 |
49 |
50 |
51 |
52 |
53 |
54 |
55 |
56 |
57 |
58 |
mean |
N |
Laemolyta fernandezi
|
3 |
5 |
12 |
10 |
22 |
15 |
15 |
6 |
3 |
1 |
53.2 |
92 |
Laemolyta garmani
|
1 |
2 |
9 |
27 |
10 |
42.9 |
49 |
Laemolyta orinocensis
|
1 |
2 |
3 |
1 |
1 |
1 |
49.2 |
9 |
Laemolyta proxima
|
1 |
35 |
111 |
87 |
9 |
45.3 |
243 |
Laemolyta taeniata
|
7 |
32 |
90 |
74 |
3 |
44.2 |
206 |
In his original description of
Laemolyta taeniata
,
Kner (1859)
mentioned that
two specimens
from Barra do rio Negro had thinner bodies, and some other divergent unspecified characters relative to the other examined specimens. One of these specimens, considered to be the
syntype
of
L. taeniata
(
NMW 56988
:2) was examined and proved to be identical to all the other specimens of
L. garmani
studied. This species was collected in sympatry with
Laemolyta proxima
and
L. taeniata
in
Peru
.