Review of the genus Cobitis in the Middle East, with the description of eight new species (Teleostei: Cobitidae)
Author
Freyhof, Jörg
Author
Bayçelebi, Esra
Author
Geiger, Matthias
text
Zootaxa
2018
2018-12-21
4535
1
1
75
journal article
27727
10.11646/zootaxa.4535.1.1
a047bcd9-ab65-4e3f-b07a-c830c7af1072
1175-5326
2615773
ABE9DB1F-7378-4571-90C4-A3FDB66527F3
Cobitis fahireae
Erk'akan,
Atalay-Ekmekçi & Nalbant, 1998
(
Fig. 11–13
)
Cobitis fahireae
Erk'akan,
Atalay-Ekmekçi & Nalbant, 1998
: 10
, fig. 2 (
type
locality:
Turkey
: Küçük Menderes, Selçuk-
Aydin
).
Cobitis vardarensis kurui
Erk'akan,
Atalay-Ekmekçi & Nalbant, 1998
: 13
, fig. 6 (
type
locality:
Turkey
: Menderes River, Selçuk-Aydin, Saplik Bridge).
Cobitis damlae
Erkakan & Özmedir, 2014
: 276
, fig. 1 (type locality:
Turkey
: Gölhisar prov.: Dalaman stream, 37.148 29.661).
Material examined.
FSJF 1975, 2,
46–62 mm
SL;
Turkey
:
İzmir
prov.: Bakır River at Karadere about
2 km
northeast of Kınık, 39.100 27.400.—FSJF 2294, 16,
42–76 mm
SL;
Turkey
:
İzmir
prov.: stream Çiçekli, a tributary to stream Nif at Çiçekli, 38.505 27.272.—FSJF 2397, 11,
47–67 mm
SL;
Turkey
:
Balıkesir
prov.: stream Madra about
3 km
south of Altınova, 39.218 26.819.—HUIC uncat.,
paratypes
, 2, 44–
45 mm
SL;
Turkey
:
İzmir
prov.: stream Nif.—FSJF 3692, 4,
42–55 mm
SL;
Turkey
:
Burdur
prov.: stream Bayındır
3 km
west of Çavdır, 37.149 29.661.—FSJF 3703, 3,
33–57 mm
SL;
İzmir
prov.: stream Develi
1 km
south of Develi, 38.201 27.171.—HUIC uncat.,
holotype
of
C. kurui
,
44.5 mm
SL;
paratype
of
C. kurui
,
41 mm
SL;
Turkey
:
Aydın
prov.: Menderes River, Saplık bridge.—FSJF 3709, 1,
62 mm
SL;
Turkey
:
Aydın
prov.: Akçay River
10 km
south of Nazilli, 37.810 28.315.—ZMH 4752, 6,
42–59 mm
SL;
Turkey
: Golusar Gölü, SW
Anatolia
.
Material used in molecular genetic analysis.
FSJF DNA-308;
Turkey
:
Balıkesir
prov.: stream Madra about
3 km
south of Altınova, 39.218 26.819. (GenBank accession numbers:
KJ553185
,
KJ553276
).
—
FSJF DNA-2815;
Turkey
:
Burdur
prov.: stream Bayındır
3 km
west of Çavdır, 37.149 29.661. (BLOLD accession numbers: BOLD EUFWF2721- 18 to EUFWF2723-18).—FSJF DNA-2855;
Turkey
:
İzmir
prov.: stream Develi about
1 km
south of Develi, 38.201 27.171. (BOLD accession numbers: BOLD EUFWF2736-18 to EUFWF2738-18).—FSJF DNA-266
Turkey
:
İzmir
prov.: stream Çiçekli, a tributary to stream Nif at Çiçekli, 38.505 27.272. (BOLD accession number: EUFWF4326-18).
Diagnosis.
Cobitis fahireae
is distinguished from
C. elongatoides
,
C. pontica
and
C. tanaitica
by having a small or no black spot at the caudal-fin base (vs. roundish or ovoid, large, about size of pupil or eye) or if larger, then having one black spot at the upper and one black spot at the lower caudal-fin base (vs. always one spot only). It is distinguished from other
Cobitis
species in the eastern
Aegean
Sea basin by having one lamina circularis in the male (vs. two in
C. dorademiri
,
C. phrygica
and
C. strumicae
).
Distribution.
Cobitis fahireae
occurs in the eastern
Aegean
Sea basin where it is found from the upper Dalaman River drainage (around Gölhisar) in the south to the Madra River drainage in the north.
Remarks.
Erk'akan
et al
. (1998) described
C. fahireae
from "Küçük Menderes, Selçuk-Aydin" (= Küçük Menderes River at Selçuk in the
Aydın province
) and they described another species,
C. vardarensis kurui
, from the (Küçük) "Menderes River, Selçuk-Aydin, Saplik Bridge". Both species have been collected at the same day and probably from the same spot or close by. Despite several visits, we failed to find
Cobitis
in the remains of the Küçük Menderes River drainage. This might be related to the massive environmental changes in the area in the past 34 years. We examined one
paratype
of
C. fahireae
(from the Gediz River drainage) and the
holotype
and four
paratypes
of
C. v. kurui
from the type locality. Three
paratypes
of
C. v. kurui
are identified as
C. afifeae
(described below).
Erk'akan
et al
. (1998, 1999) report
C. fahireae
also from the lower Simav River (Marmara Sea basin; identified as
C. taenia
, see below) and from the Bakır and Gediz River drainages (
Aegean
Sea basin) and they report
C. v. kurui
from the Gediz and the Tahtalı (=Sasal) Rivers (all
Aegean
Sea basin). This suggests that both,
C. fahireae
and
C. v. kurui
should occur in sympatry in the Küçük Menderes and in the Gediz River drainages. We were not able to find more than one
Cobitis
species in the Gediz River drainage but
Güçlü & Küçük (2015)
report
C. fahireae
and
C. kurui
from the Gediz and distinguish both species by the colour of the spot at the upper caudal-fin base (black in
C. fahireae
vs. brown in
C. kurui
).
Erk'akan
et al
. (1998) described
Cobitis v. kurui
as a subspecies of
C. vardarensis
and distinguished both subspecies by the brown, very small or absent spot at the upper caudal-fin base in
C. v. kurui
(vs. large and black in
C. v. vardarensis
) and having more blotches along Z4 (no details given). Indeed, based on the description by Erk'akan
et al
. (1998) and the
types
examined, both subspecies can be immediately distinguished by the very small or absent upper caudal-fin base spot in
C. v. kurui
(vs. large in
C. v. vardarensis
) and the pigmentation in Z3 formed by one line or a narrow band of brown spots (vs. many small, brown spots the in Z3 giving it a "sandy" pattern).
Despite
Cobitis v. kurui
having been described from the same place as
C. fahireae
, Erk'akan
et al
. (1998) do not compare
C. kurui
with
C. fahireae
directly, but state that
C. kurui
is almost identical to
C. vardarensis
.
Erk'akan
et al
. (1998) distinguish
C. fahireae
from the "
Cobitis vardarensis
complex" by having a reduced pigmentation in Z3, the pigmentation in Z2 dotted and a rounded, small caudal spot. Indeed, in
C. v. vardarensis
there are many small, brown spots the in Z3 giving it a "sandy" pattern while in the types of
C. fahireae
and
C. kurui
, the pigmentation in Z3 is "reduced" as there is just one line or a narrow band of brown spots. Erk'akan
et al
. (1998) also state, that the pigmentation in Z2 is dotted in
C. fahireae
(vs. short stripes in
C. v. kurui
). However, in our own materials (e.g.
Fig. 9
) there is a great variation in this character and all intermediate character states are observed. In addition, the spot at the upper caudal-fin base was found to be small and black or brown or absent in individuals of one population and no difference in the size and the shape of the spot could be found between the
paratypes
of
C. fahireae
and
C. v. kurui
, while the
holotype
of
C. kurui
has no black spot. We found all characters distinguishing
C. fahireae
and
C. v. kurui
to be highly variable even within populations. As we fail to distinguish
C. v. kurui
from
C. fahireae
,
we have to treat both species as just one.
As
C. fahireae
and
C. v. kurui
were described in the same study, a First Reviser action is needed. The First Reviser action is the principle that in cases of conflicts between simultaneously published names, the first subsequent author can decide which name has precedence (
ICZN 1999: Article 24.2
). Here we act as the First Revisers and give precedence to
C. fahireae
over
C. v. kurui
.
Cobitis damlae
was described by Erk'akan &
Özdemir (2014)
based on one female individual from the stream Bayındır in the upper Dalaman River drainage. Erk'akan &
Özdemir (2014)
claim that
C. damlae
is a subterranean species but it has been collected from surface waters and not from an underground habitat. Erk'akan &
Özdemir (2014)
speculate that the sole individual was washed out from underground waters nearby. However, they provide no evidence for this speculation. Baran Yoğurtçuoğlu (
Ankara
) & JF visited the
type
locality of
C. damlae
in 2017 and found no spring or any subterranean waters adjacent to the
type
locality. The stream Bayındır flows down from a reservoir and we found no tributaries, which might originate from an underground source. Erk'akan &
Özdemir (2014)
mentioned the caves Keloğlan and Aslanini in the upper Dalaman River drainage about
30 km
from the
type
locality of
C. damlae
, but no troglomorphic fish have ever been reported from these caves. It remains unclear how these caves or other subterranean habitats might be connected to the stream Bayındır.
The
holotype
and single known individual of
Cobitis damlae
(
Fig. 13
) has no pigmentation and its eye is not reduced in size. Surprisingly, Erk'akan &
Özdemir (2014)
distinguished
C. damlae
by having vestigial eyes, a character state not seen from the picture. In subterranean fishes, the eye is usually reduced in size already in the very early phase of adaptation to an underground environment, while the pigmentation pattern is reduced later on, resulting in many subterranean fish with very small eyes but still having a colour patter (
Proudlove 2003
). Furthermore, many subterranean fish with eyes become grey or brown, if exposed to light for some days (own observation). The situation is the opposite in
C. damlae
. Here the pigmentation is absent, but the eye is fully developed. On the picture (
Fig. 13
), the eye-background is orange, suggesting, that the animal is albinotic. While it is impossible to exclude that the
holotype
of
C. damlae
originates from an underground habitat, there are strong indications that it is just an albinotic individual of a surface population.
Erk'akan &
Özdemir (2014)
identified the pigmented
Cobitis
from the stream Bayındır as
C. battalgilae
(see discussion above, identifying this population as
C. phrygica
) but we found
C. fahireae
to be common in the stream Bayındır. Indeed, the absence of pigmentation and the fact that the
holotype
of
C. damlae
is a female makes it difficult to identify it as one of the two
Cobitis
species present in the area (
C. fahireae
,
C. phrygica
). Other characters given by Erk'akan &
Özdemir (2014)
do not allow distinguishing these two
Cobitis
species. Erk'akan &
Özdemir (2014:278)
distinguish
C. damlae
from
C. battalgilae
(=
C. phrygica
) by having 6½ branched dorsal-fin rays (vs. 8) but the individual of
C. phrygica
shown by Erk'akan &
Özdemir (2014
:
Fig. 2
[a drawing by T. Nalbant already published by Erk'akan
et al
. 1999: Fig. 8]) has 6½ branched dorsal-fin rays (indeed it has 6 branched dorsal-fin rays as T. Nalbant always ignored the ½ ray on his drawings) and all
Cobitis
examined for this study have 6½ or 7½ branched dorsal-fin rays. Erk'akan &
Özdemir (2014:279)
further distinguish
C. damlae
from
C. battalgilae
(=
C. phrygica
) by having 8+8 branched caudal-fin rays (vs. 7+7) and 6½ branched pectoral-fin rays (vs. 7
–
8). A range of 7+7, 8+7 or 8+8 is common in populations of the
Cobitis
species examined for this study and
C. fahireae
caught by us at the type locality of
C. damlae
have 7+7 branched caudal-fin rays. No details are given how the pectoral-fin rays are counted. Erk'akan &
Özdemir (2014)
refer to
Economidis
et al
. (1996)
and Erk'akan
et al
. (1998) for methods of count. Neither
Economidis
et al
. (1996)
nor Erk'akan
et al
. (1998) count the pectoralfin rays as ½ and we can only suspect, that there are 7 branched pectoral-fin rays in the type of
C. damlae
(vs.
7
–
8 in
C. battalgilae
=
C. phrygica
). In the
C. fahireae
from the type locality of
C. damlae
as well as in
C. phrygica
, 6– 10 branched pectoral-fin rays are very common and a range of 2–3 rays is typical in all species. The only indication given is the shape of the external part of the suborbital spine, which is simple in
C. phrygica
and bifurcate in
C. fahireae
. In the type of
C. damlae
, the spine is bifurcate (Erk'akan &
Özdemir 2014
). Furthermore, the type of
C. damlae
is a fully ripe female individual of only
64 mm
SL. Females of
C. phrygica
grow much larger and reach up to
119 mm
SL. As the type of
C. damlae
has a bifurcate suborbital spine, is relatively small and as we found only
C. fahireae
at the type locality, we are unable to distinguish
C. damlae
from
C. fahireae
. Our molecular data also place
Cobitis
from the type locality of
C. damlae
close to
C. fahireae
and we found no morphological character to distinguish these fishes from
C. fahireae
based on our materials examined and details given in the description by Erk'akan &
Özdemir (2014)
. Therefore, we treat
C. damlae
as a synonym of
C. fahireae
.
FIGURE 11.
Cobitis fahireae
, FSJF 1975, male, 46 mm SL; female, 62 mm SL; Turkey: Bakır River; FSJF 3703, female, 57 mm SL; Turkey: stream Develi; FSJF 3692, female, 51 mm SL, male 40 mm SL; Turkey: Büyük Menderes River.
FIGURE 12.
Cobitis fahireae
, HUIC uncat., holotype of
C. kurui
, 44.5 mm SL; Turkey: Küçük Menderes River.
FIGURE 13.
Cobitis fahireae
, from the top: HUIC, uncat., holotype of
C. damlae
, female, 64 mm SL; Turkey: stream Bayındır. Photo: Füsun Erk'akan; FSJF 3692, female, 55 mm SL; Turkey: stream Bayındır.
Our molecular data suggest that there is substantial diversity within the species we call
C. fahireae
. We found a minimum COI K2P distance of 1.0% between
Cobitis
from the Dalaman / Gediz Rivers and the Şaşal River and 1.3% K2P distance between
Cobitis
from the Dalaman / Gediz Rivers and the Madra River.
Cobitis
from the Madra River are distinguished from those from the Şaşal River by 1.8%.
Perdices
et al
. (2018)
found very little molecular difference between
Cobitis
populations from the Gediz and Bakir Rivers. We found no differences between
Cobitis
populations from the Gediz and Dalaman Rivers. As the Küçük Menderes River is situated between the Gediz and the Dalaman Rivers, we could speculate, that this group is the one the
type
of
C. fahireae
was collected from. On the other hand, the Küçük Menderes River might have (had) an own fish fauna and its estuary is only
25 km
southwest of the Şaşal River estuary. Both rivers are very likely to have flown together during the last glaciation. Therefore, it is likely that
Cobitis
from the Şaşal River are identical with
C. fahireae
from the Küçük Menderes River. More fieldwork is urgently needed, especially in the Küçük Menderes River, to locate
C. fahireae
there.
Our own molecular data (
Fig. 1
) and
Perdices
et al
. (2018)
place
Cobitis fahireae
in the
C. taenia
species group (
C. avicennae
,
C. elongatoides
,
C. emrei
,
C. fahireae
,
C. faridpaki
,
C. pontica
,
C. puncticulata
,
C. satunini
,
C. saniae
,
C. splendens
,
C. tanaitica
,
C. taurica
and
C. vardarensis
). Based on DNA barcoding,
C. fahireae
is well separated from all other
Cobitis
included in this study and it is distinguished from its closest relative,
C. tanaitica
,
by a minimum K2P distance of 4.5%, also supported as single PTP entity. It is further distinguished from
C. elongatoides
and
C. pontica
by having one line or a narrow band of brown spots in Z3 (vs. many small, brown spots the in Z3 giving it a "sandy" pattern). See below for details to distinguish
C. fahireae
from other species in the
C. taenia
species group in
Anatolia
(
C. puncticulata
,
C. splendens
,
C. taenia
,
C. satunini
) and from other
Cobitis
species found in the eastern Aegean Sea basin.