Jump to content

Southern dwarf siren: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
m Materialscientist moved page Southern Dwarf Siren to Southern dwarf siren: MOS:LIFE
mNo edit summary
Line 1: Line 1:
{{Taxobox
{{Taxobox
| name = Southern Dwarf Siren
| name = Southern dwarf siren
| image = P axanthus USGS.jpg
| image = P axanthus USGS.jpg
| image_width = 240px
| image_width = 240px
Line 18: Line 18:
}}
}}


The '''Southern Dwarf Siren''' ('''''Pseudobranchus axanthus''''') is a perennibranch [[salamander]] lacking hind legs. Found exclusively in [[Florida]], it is one of two currently recognized species of dwarf sirens. Two [[subspecies]] are currently recognized; ''P. a. axanthus'', the narrow-striped dwarf siren, and ''P. a. belli'', the Everglades dwarf siren.
The '''southern dwarf siren''' ('''''Pseudobranchus axanthus''''') is a perennibranch [[salamander]] lacking hind legs. Found exclusively in [[Florida]], it is one of two currently recognized species of dwarf sirens. Two [[subspecies]] are currently recognized; ''P. a. axanthus'', the narrow-striped dwarf siren, and ''P. a. belli'', the Everglades dwarf siren.


==Physical description==
==Physical description==
Southern dwarf sirens are thin, slimy salamanders that are frequently mistaken for [[eels]]. Dwarf sirens have long bodies with bushy [[gill]]s and small, three-toed forelegs. Coloration is generally brown, black, or gray, with yellow or tan stripes on the back and sides. Adults reach a maximum length of 10–25 cm.
Southern dwarf sirens are thin, slimy salamanders that are frequently mistaken for [[eels]]. they have long bodies with bushy [[gill]]s and small, three-toed fore legs. Coloration is generally brown, black, or gray, with yellow or tan stripes on their backs and sides. Adults reach a length of 10–25 cm.


Southern dwarf sirens can easily be distinguished from [[amphiuma]]s by size and the presence of hind legs, and from ''Siren spp.'' salamanders by the presence of three toes on each foot. Distinguishing between ''Pseudobranchus axanthus'' and ''Pseudobranchus striatus'' is more difficult, requiring comparison of patterns with a field guide, known distribution, or a karyotype test. ''P. axanthus'' has 32 chromosomes while ''P. striatus'' has 24. A costal groove count may assist in differentiating ''P. a. axanthus'' and ''P. a. belli'', as the former has 34–37 costal grooves while the latter has 29–33 (Petranka, 1998).
Southern dwarf sirens can easily be distinguished from [[amphiuma]]s by size and the presence of hind legs, and from ''Siren'' spp. salamanders by the presence of three toes on each foot. Distinguishing between ''P. axanthus'' and ''P. striatus'' is more difficult, requiring comparison of patterns with a field guide, known distribution, or a karyotype test. ''P. axanthus'' has 32 chromosomes, while ''P. striatus'' has 24. A costal groove count may assist in differentiating ''P. a. axanthus'' and ''P. a. belli'', as the former has 34–37 costal grooves, while the latter has 29–33 (Petranka, 1998).


==Distribution==
==Distribution==
''P. axanthus'' is found throughout eastern Florida, with ''P. a. axanthus'' located in the northern two thirds of the range and ''P. a. belli'' located in the southern third. ''P. axanthus'' prefers cypress ponds, ditches, swamps and marshes, and other aquatic and semi-aquatic habitats (Petranka, 1998). ''P. axanthus'' are frequently associated with water hyacinth.
''P. axanthus'' is found throughout eastern Florida, with ''P. a. axanthus'' located in the northern two-thirds of the range and ''P. a. belli'' located in the southern third. ''P. axanthus'' prefers cypress ponds, ditches, swamps and marshes, and other aquatic and semiaquatic habitats.<ref>Petranka, 1998</ref> ''P. axanthus'' is frequently associated with water hyacinth.


==Reproduction==
==Reproduction==
Little is known about the reproduction of wild sirenid salamanders. Eggs of ''P. axanthus'' have been found from November through March and are usually attached singly to aquatic plants. Eggs average 3&nbsp;mm in diameter and have three jelly envelopes (Petranka, 1998).
Little is known about the reproduction of wild sirenid salamanders. Eggs of ''P. axanthus'' have been found from November through March, and are usually attached singly to aquatic plants. Eggs average 3&nbsp;mm in diameter and have three jelly envelopes.<ref>Petranka, 1998</ref>


In captivity, eggs were attached singly at night to floating vegetation in groups of two to five a day. Larvae hatch out at approximately 5&nbsp;mm after ~3 weeks.
In captivity, eggs were attached singly at night to floating vegetation in groups of two to five a day. Larvae hatch out at about 5&nbsp;mm after around three weeks.


==Diet==
==Diet==
Southern dwarf sirens eat a variety of food items, including small worms, chironomids, amphipods, and ostracods (Petranka, 1998). Dwarf sirens have surprisingly small mouths, but will likely eat any invertebrate that they can swallow. In captivity, adult ''[[Daphnia magna]]'', whiteworms, blackworms, and tubifex worms are readily taken.
Southern dwarf sirens eat a variety of food items, including small worms, chironomids, amphipods, and ostracods.<ref>Petranka, 1998</ref> Dwarf sirens have surprisingly small mouths, but will likely eat any invertebrate they can swallow. In captivity, adult ''[[Daphnia magna]]'', whiteworms, blackworms, and tubifex worms are readily taken.


==Ecology==
==Ecology==
During dry spells, ''P. axanthus'' is known to aestivate in muddy burrows during dry spells, and adults have been kept for periods longer than two months in dry soil with no ill effects in laboratory (Petranka, 1998).
During dry spells, ''P. axanthus'' is known to aestivate in muddy burrows, and adults have been kept for periods longer than two months in dry soil with no ill effects in the laboratory.<ref>Petranka, 1998</ref>


==References==
==References==

Revision as of 22:52, 19 March 2013

Southern dwarf siren
Scientific classification
Kingdom:
Phylum:
Subphylum:
Class:
Subclass:
Order:
Suborder:
Family:
Genus:
Species:
P. axanthus
Binomial name
Pseudobranchus axanthus
Netting & Goin, 1942[1]

The southern dwarf siren (Pseudobranchus axanthus) is a perennibranch salamander lacking hind legs. Found exclusively in Florida, it is one of two currently recognized species of dwarf sirens. Two subspecies are currently recognized; P. a. axanthus, the narrow-striped dwarf siren, and P. a. belli, the Everglades dwarf siren.

Physical description

Southern dwarf sirens are thin, slimy salamanders that are frequently mistaken for eels. they have long bodies with bushy gills and small, three-toed fore legs. Coloration is generally brown, black, or gray, with yellow or tan stripes on their backs and sides. Adults reach a length of 10–25 cm.

Southern dwarf sirens can easily be distinguished from amphiumas by size and the presence of hind legs, and from Siren spp. salamanders by the presence of three toes on each foot. Distinguishing between P. axanthus and P. striatus is more difficult, requiring comparison of patterns with a field guide, known distribution, or a karyotype test. P. axanthus has 32 chromosomes, while P. striatus has 24. A costal groove count may assist in differentiating P. a. axanthus and P. a. belli, as the former has 34–37 costal grooves, while the latter has 29–33 (Petranka, 1998).

Distribution

P. axanthus is found throughout eastern Florida, with P. a. axanthus located in the northern two-thirds of the range and P. a. belli located in the southern third. P. axanthus prefers cypress ponds, ditches, swamps and marshes, and other aquatic and semiaquatic habitats.[2] P. axanthus is frequently associated with water hyacinth.

Reproduction

Little is known about the reproduction of wild sirenid salamanders. Eggs of P. axanthus have been found from November through March, and are usually attached singly to aquatic plants. Eggs average 3 mm in diameter and have three jelly envelopes.[3]

In captivity, eggs were attached singly at night to floating vegetation in groups of two to five a day. Larvae hatch out at about 5 mm after around three weeks.

Diet

Southern dwarf sirens eat a variety of food items, including small worms, chironomids, amphipods, and ostracods.[4] Dwarf sirens have surprisingly small mouths, but will likely eat any invertebrate they can swallow. In captivity, adult Daphnia magna, whiteworms, blackworms, and tubifex worms are readily taken.

Ecology

During dry spells, P. axanthus is known to aestivate in muddy burrows, and adults have been kept for periods longer than two months in dry soil with no ill effects in the laboratory.[5]

References

  1. ^ Amphibian Species of the World 5.5. research.amnh.org/vz/herpetology/amphibia.
  2. ^ Petranka, 1998
  3. ^ Petranka, 1998
  4. ^ Petranka, 1998
  5. ^ Petranka, 1998

Petranka, James W.; 1998, Salamanders of the United States and Canada, Smithsonian Institution Press, Washington.