|
Stygichthys typhlops
Brittan & Böhlke, 1965 |
|
Brazilian blind characid |
Common Name: Brazilian blind
characid (E); piabinha cega (P).
Etymology: stygos (Gr) from the
underworld in the Greek mythology; ichthyos (Gr) fish; typhlos (Gr) blind;
ops (Gr) eye.
Major Synonyms: None.
History: The species was described based on only one specimen captured on 16 May 1962
by Joseph A. Tosi, Jr., an ecologist with the Instituto de Agricultura of
the Organization of American States. The fish was captured in water
brought up from a depth of 30 m during a well-drilling operation.
Early in 2004 researchers of the Instituto de Biociências
and the Museum of Zoology of the University of Sâo Paulo, Brazil, captured
25 new specimens. |
|
Picture at:
http://www.ciencia-shop.com.br/shop/especial/mat135.asp |
|
Morphological Characteristics:
Troglomorphic Characters:
It may reach 50
mm SL. There is no
distinct lateral-line system.
Eye Condition: No externally visible eyes.
Pigmentation: Totally depigmented.
Scales:
Swim (gas) bladder: |
|
|
|
Distribution:
Brazil: Minas Gerais state: in one well location at Jaiba. The
precise location is unknown. Jaiba may refer to an area (Serra de Jaíba)
or to a town, near to which the well could be situated. It is the
area between Januaria and Janaúba, in northern Minas Gerais State,
central-eastern Brazil (Trajano, personal communication) (ca.16o15' N,
44o00' W). |
|
|
|
Habitat and
Ecology: Groundwater, obtained from a well drilled at 30 m. |
|
Food and Feeding: Although the
tooth structure seems to indicate a mostly vegetarian diet, it is unlikely
that they maintain such a diet in the underground environment. This
may be a relictual morphological feature. Cannibalism has been
reported (Quinto, 2004). |
|
Reproduction and Development: |
|
Other Behaviors: |
|
Conservation
Status: Data deficient.
Major Threats:
Lowering of the water table. |
|
Conservation Plans: |
Phylogenetic Relationships:
Unlike the Mexican cave tetra, the ancestral form of
this fish has yet to be determined. The Brazilian blind characid has
a number of features typical of the Tetragonopterinae. More
specifically, it may be related to the Hyphessobrycon-Hasemania
complex, because of this group’s reduction in the circumorbital bones;
however that just may be a coincidence given that the reduction of those
bones is a convergent
feature among cave fishes. They also differ from other
Tetragonopterinae in the large number of inner premaxillary and maxillary
teeth, as well as the small number of anal rays which are unusual for this
group of characids (Romero & McLeran 2000). |
|
|
| |
|
|
| |
|
|