A Description of a new Valvata (Mollusca: Valvatidae) from Armenia
Author
Walther, Frank
Zoological Museum, Centre of Natural History, University of Hamburg, Martin-Luther-King Platz 3, D- 20146 Hamburg, Germany, e-mail: fw. walther @ googlemail. com
Author
Glöer, Peter
Schulstr. 3, D- 25491 Hetlingen, Germany, email: gloeer @ malaco. de
text
Ecologica Montenegrina
2019
2019-10-31
24
1
5
journal article
56112
10.37828/em.2019.24.1
1a37c0b2-d394-46e2-af88-1cdffeef6629
2336-9744
8056212
urn:lsid:zoobank.org:pub:E2F78A29-584A-4B11-9DF0-7F9093964CBE
Valvata
(
Tropidina
)
armeniaca
n. sp.
(
Figs. 1-3
, 7-8)
Valvata pulchella
[not Studer, 1798] –
Akramowski 1968: 26
.
Valvata pulchella
[not Studer, 1798] –
Akramowski 1976: 90
, text-fig. 24, pl. 1 fig. 3.
Type material:
Holotype
: Shell height
1.5 mm
, width
2.5 mm
, from type locality
(
ZMH 59491
)
;
Paratypes
: from type locality (
ZMH 59492
,
3 specimens
in ethanol); from type locality (
FW 13603
; 1 dry shell);
Ararat Province
,
Jrahovit
, ditch S of the cemetery,
40.0450°N
44.4880°E
,
850 m
asl
.,
26 Aug. 2018
,
F. Walther
leg. (
FW 14008
,
1 specimen
in ethanol)
.
Type
locality
:
Armenia
,
Armavir Province
, bridge over
river Kasakh
,
1.6 km
W of Vagharshapat
,
40.1650°N
44.2558°E
,
870 m
asl
.,
27 Aug. 2018
,
F. Walther
leg.
Etymology
: The new species is named after
Armenia
, the country of its origin.
Figure 1
. The sampling sites of
Valvata
(
Tropidina
)
armeniaca
n.sp.
(red squares, 1: type locality, 2: Jharovit).
Description
: The corneous shell has 2.5 circular whorls with a low spire and a blunt apex. The surface has weak growth lines. Within the umbilicus, the penultimate whorl is covered to 75% of its width by the body whorl (measured at the aperture). Shell height
1.2-1.7 mm
, diameter
2.2-2.5 mm
. The umbilicus is
0.8 mm
wide (32-36 % of the shell diameter). The aperture is circular.
Anatomy
: The penis is long and cylindrical, tapered at the distal end, which corresponds to the drawing of
Akramowski (1976: 89)
, and as it is in
Valvata nowshahrenis
(
Glöer & Pešić 2012
, fig. 14) and all other
Valvata
spp.
The male and female sex tract in
Valvata
spp.
is very simple and not suitable for species identification.
Figure 2.
1-3:
Valvata
(
Tropidina
)
armeniaca
n.sp.
(holotype) and 4-6:
Valvata
(
Tropidina
)
nowshahrensis
, 7-8:
Valvata
(
Tropidina
)
kebapcii
(holotype), 9-10:
Valvata
(
Tropidina
)
armeniaca
n.sp.
(paratype) photographed under ethanol to show the characteristic mantle pigmentation.
Differentiating features
:
Valvata armeniaca
n. sp.
has a smaller shell with a narrower umbilicus than
V. nowsharensis
and
V. kebapcii
Odabaşi, Glöer & Yıldırım, 2015
. The exact differences between the species are displayed in
Table 1
.
Distribution
: In addition to the
type
locality,
V. armeniaca
n. sp, is also known from Jrahovit, from where
Akramowski (1976
: pl. 1 fig. 3) figured it as
V. pulchella
. Both localities are in the drainage area of river Aras making it likely that the new species is also distributed in other wetlands of the Aras drainage system. Records of
V. pulchella
from the lower part of river Aras in
Azerbaijan
(
Aliyev 2014
) could refer to the new species.
Table 1
. Distinguishing characters of
Valvata
(
Tropidina
)
armeniaca
n. sp.
and related species.
V. armeniaca
|
V. nowsharensis
|
V. kebapcii
|
n.sp.
|
Glöer & Pešić, 2012
|
Odabaşi et al., 2015
|
shell diameter |
2.2-2.5 mm |
3.2-3.3 mm |
3.5-4.0 mm |
shell height |
1.2-1.7 mm |
2.3 mm |
<2.6 mm |
umbilicus in % of shell diameter |
32-36 % |
45-48 % |
40 % |
part of penultimate whorl covered by the body whorl (umbilical view) |
75% |
<25% |
50% |
number of whorls |
2.5 |
3 |
3.5 |
Habitat
(
Fig. 3
): Living specimens were collected in dense submerged vegetation. At the
type
locality river Kasakh has a relatively weak current and carries less water than further upstream due to water withdrawal for the intense agriculture of the surrounding areas. At Jrahovit it was found among partly submersed
Nasturtium
at a small open spot in the dense reed vegetation of a ditch.
Akramowski (1976)
mentions the species from weakly flowing water of summer-dry marshes around springs and in drainage canals.
Figure 3.
River Kasakh at the type locality of
Valvata
(
Tropidina
)
armeniaca
n.sp.
Associated species
:
Hippeuthis complanatus
(Linnaeus, 1758);
Lymnaea
spec.
;
Pisidium
spec.
,
Shadinia terpoghassiani
(
Zhadin, 1952
)
and an unidentified bithyniid.
Discussion
: When describing a new
Valvata
from
Armenia
it is necessary to discuss the identity of
Valvata brandti
Westerlund, 1897
, the only
Valvata
species
described from that country before. Although we had no access to the type material we feel entitled to correct some inaccuracies in
Haszprunar (2014)
concerning the origin and the synonymy of the taxon. The original description of
V. brandti
is based on two lots. One was collected by A. Brandt in Lake Sevan, while the other was found by L. Młokosiewicz near Lagodekhi in
Georgia
. Between both localities is a distance of more than
150 km
. The Lagodekhi record belongs to
Caspicyclotus sieversi
, the only Caucasian member of the terrestrial prosobranch family
Cyclophoridae
and indeed very similar to some
Valvata
species.
The other lot, however, seems to belong to
Valvata piscinalis
, which is known to occur in Lake Sevan (e.g.
Mashkova et al. 2018
). The name
V. brandti
could therefore also be a synonym of
V. piscinalis
according to a later definition of the taxon by a
lectotype
. In any case,
V. brandti
is very different from the species described above.