:''Common names: hognose pitvipers.
[Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere'' Ithaca and London: Comstock Publishing Associates. 870 pp., 1500 plates. .]''
''Porthidium'' is a
genus of
venomous pitvipers
The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . crotaline snakes (from grc, κρόταλον ''krotalon'' castanet), or pit adders, are a subfa ...
found in
Mexico and southward to northern
South America.
The name is derived from the
Greek word ''portheo'' and the suffix ''-idus'', which mean "destroy" and "having the nature of", apparently a reference to the venom.
As of August 2016 nine
species are recognized as being valid.
The snakes of the genus ''
Hypnale
:''Common names: hump-nosed vipers,Gloyd HK, Conant R. 1990. Snakes of the Agkistrodon Complex: A Monographic Review. Society for the Study of Amphibians and Reptiles. 614 pp. 52 plates. LCCN 89-50342. . hump-nosed pit vipers.Brown JH. 1973. Toxi ...
'' in southern
India and
Sri Lanka
Sri Lanka (, ; si, ශ්රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...
look quite similar to those of this genus, possibly an example of
convergent evolution.
Description
''Porthidium'' is a genus of small
species, adults ranging in total length (including tail) from (''
P. dunni'' and ''
P. yucatanicum'') to (''
P. lansbergii'' and ''
P. ophryomegas''). In addition, the body shape ranges from relatively slender (''P. ophryomegas'') to relatively stout (''
P. nasutum''). All have a sharply defined ''
canthus rostralis'' and a
rostral scale that is higher than it is broad. The tip of the snout may be slightly to moderately elevated (''
P. hespere'', ''P. lansbergii'', ''P. ophryomegas'' and ''
P. volcanicum''), strongly elevated (''P. dunni'' and ''P. yucatanicum''), or not elevated at all.
All species have a color pattern that usually consists of a brown or gray ground color, overlaid with a series of dark
paraventral blotches that are separated by a pale and narrow vertebral stripe. The blotches are square, rectangular, or triangular in shape. In some species, the color pattern is determined by the sex.
Geographic range
Found in
Mexico (
Colima,
Oaxaca and
Chiapas
Chiapas (; Tzotzil language, Tzotzil and Tzeltal language, Tzeltal: ''Chyapas'' ), officially the Free and Sovereign State of Chiapas ( es, Estado Libre y Soberano de Chiapas), is one of the states that make up the Political divisions of Mexico, ...
on the Pacific side, the
Yucatán Peninsula on the Atlantic side) southward through
Central America to northern
South America (
Ecuador in the Pacific lowlands, northern
Venezuela in the Atlantic lowlands).
Species
''*) Not including the
nominate subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
.''
T)
Type species.
''
Nota bene'': A
binomial authority
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
in parentheses indicates that the species was originally described in a genus other than ''Porthidium''.
References
Further reading
*
Cope ED (1871). "Ninth Contribution to the Herpetology of Tropical America". ''Proceedings of the Academy of Natural Sciences of Philadelphia'' 23 (2): 200-224. (''Porthidium'', new genus, p. 207).
External links
*
{{Taxonbar, from=Q1569946
Taxa named by Edward Drinker Cope