Species of snake
The
viperine water snake
or
viperine snake
(
Natrix maura
) is a semiaquatic, fish-eating
natricine
water snake. Despite its common names, it is not a member of the subfamily
Viperinae
. It was given its common names due to exhibiting a dorsal colour pattern that superficially resembles that of sympatric
adder
species. In comparison to other
Natrix
species its head is also somewhat wider and more distinct from the neck. Like most members of the Natricinae it possesses a venom gland on each side of the upper jaw (
Duvernoy's gland
) that produces a mild venom that may play a role in swallowing or digestion. The gland is not associated with an enlarged specialized tooth and the venom has to be applied by chewing. The species usually does not bite as a means of defense, and the effect of a bite would be harmless to humans.
Behaviour
[
edit
]
The viperine snake looks like an adder and occasionally behaves like one. It is known to strike like an adder, but not to bite. It spends most of its time in water hunting fish, frogs and other aquatic animals. The species is
diurnal
.
[2]
Geographic range
[
edit
]
The viperine snake is found in southwestern Europe and northwestern Africa. Specifically,
N. maura
is found in the European countries of
Portugal
,
Spain
,
Andorra
,
France
, northwestern
Italy
, and
Switzerland
. It has spread to areas of
England
, as well
[
citation needed
]
. It is found in African countries of
Morocco
, northern
Algeria
, northwestern
Libya
, and northern to central
Tunisia
. It was introduced to
Mallorca
in the Baleares (not indicated on the distribution map).
[2]
Description
[
edit
]
N. maura
is grey, brown, or reddish dorsally, with a black zigzag vertebral stripe, and lateral series of black ocelli with yellow centers. The labials are yellow with black sutures. It has a diagonal dark band on each temple, and another behind it on each side of the neck. Ventrally, it is yellow or red, checkered with black, or all black.
The strongly keeled dorsal scales are arranged in 21 rows. The ventrals are 147?160; the anal plate is divided; and the paired subcaudals number 47?72.
Adults may attain a total length of 85 cm (33 inches), with a tail 17 cm (7 inches) long.
[3]
Habitat
[
edit
]
The viperine snake is found in
rivers
and
lakes
, and has also been recorded from areas of brackish water.
Invasion
[
edit
]
The species is invasive on Mallorca.
[4]
N. maura
predates on
Pelophylax perezi
among other prey on Mallorca. Research by Moore et al. 2004 suggests
trophic subsidy
provided by
P. perezi
is maintaining higher numbers of the invader than would otherwise occur.
[4]
N. maura
has altered the behavior of Mallorcan prey. Moore et al. 2004 found that the higher numbers mentioned above are allowing the invader to exert such high pressure that prey species such as the
Majorcan midwife toad
(
Alytes muletensis
) have retreated entirely to habitats too steep for
N. maura
.
[4]
See also
[
edit
]
References
[
edit
]
- ^
Jose Antonio Mateo Miras, Marc Cheylan, M. Said Nouira, Ulrich Joger, Paulo Sa-Sousa, Valentin Perez-Mellado, Benedikt Schmidt, Andreas Meyer, Roberto Sindaco, Antonio Romano, Inigo Martinez-Solano (2009).
"
Natrix maura
"
.
IUCN Red List of Threatened Species
.
2009
: e.T61538A12510365.
doi
:
10.2305/IUCN.UK.2009.RLTS.T61538A12510365.en
. Retrieved
20 November
2021
.
{{
cite journal
}}
: CS1 maint: multiple names: authors list (
link
)
- ^
a
b
UIcnmed.org
- ^
Boulenger GA
. 1893.
Catalogue of the Snakes in the British Museum (Natural History). Volume I., Containing the Families ... Colubridæ Aglyphæ, part.
London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I-XXVIII. (
Tropidonotus viperinus
, pp. 235?237).
- ^
a
b
c
Kraus, Fred (2015-12-04). "Impacts from Invasive Reptiles and Amphibians".
Annual Review of Ecology, Evolution, and Systematics
.
46
(1).
Annual Reviews
: 75?97.
doi
:
10.1146/annurev-ecolsys-112414-054450
.
ISSN
1543-592X
.
External links
[
edit
]
Further reading
[
edit
]
- Arnold EN
, Burton JA. 1978.
A Field Guide to the Reptiles and Amphibians of Britain and Europe
. London: Collins. 272 pp.
ISBN
0-00-219318-3
. (
Natrix maura
, pp. 202?204 + Plate 37 + Map 115).
- Linnaeus C
. 1758.
Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, locis. Tomus I. Editio Decima, Reformata.
Stockholm: L. Salvius. 824 pp. (
Coluber maurus
, new species, p. 219). (in Latin).
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