Chapalichthys encaustus

Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Chapalichthys encaustus
Original Description: 

  JORDAN, D. S. & J. O. SNYDER (1900): Notes on a collection of fishes from the rivers of Mexico, with description of twenty new species. Bulletin of the United States Fish Commission. 1899: pp 115 - 147

Etymology: 

  The name "encaustus" (lat.) means “burnt in”, probably because of the lateral marks of the adult fish.

Holotype: 

  Collection-number: L.S.Jr.Univ.Mus. 6163. The Holotype is an adult female, the SL is not documented by the describer. The type has been collected by J. O. Snyder, 26.12.1898.

English Name: 
Barred Splitfin
Mexican Name: 
Pintito de Ocotlán
Synonyms: 

Characodon encaustus   Jordan & Snyder, 1900

Karyotype: 

  The Karyotype describes the number and appearance of chromosomes during the phase of condensation, classified by the position of the centromere (Levan et al., 1964).

The following abbreviations are employed:

 

M = large metacentric chromsome (a result of Robertsonian fusion)

m = small metacentric chromsome (centromere at medium position)

sm = submetacentric chromsome (centromere at submedian position)

smst = submetacentric-subtelocentric chromosome (continous series)

st = subtelocentric chromosome (centromere at subterminal region)

stt = subtelocentric-acrocentric chromosome (continous series)

t = acrocentric chromosome (centromere at terminal region)

 

The Karyotype of Chapalichthys encaustus, following Uyeno, Miller & Fitzsimons, 1983:

2n = 36    12M/ 4sm/ 16st/   

Size: 
The maximum known SL is 93mm (Miller et al, 2005).
Terra typica: 

  The Holotype had been caught in the Lago de Chapala, near Ocotlán in Jalisco.

Status after IUCN: 

  not mentioned

Status following other sources: 

  Vulnerable; Comment: Declining in Chapala-Lake

Distribution and ESU's: 

  This species is widely distributed on the Pacific Slope. It inhabits the basin of ríos Lerma-Grande de Santiago (above El Salto de Juanacatlán), in the states Jalisco and Michoacán.

Habitat: 

  This fish lives in quiet waters of lakes, ponds and river channels, where currents are usually slow to none, but may be moderate. Vegetation there is usually sparse to none. When there is vegetation, it is composed of green algae, water hyacinths and Scirpus. The substrates are made of silt, mud, clay, sand and rocks. The waterbodies are rarely deeper than 1.3m, commonly the depth is less than 1m. The water can be from turbid to muddy (after Miller).

  Brian Kabbes caught this species in a channel in Michoacán in December 1998. The water had been muddy with the sight below 10cm. The water temperature had been around 16°C in the morning. In the Lago de Chapala, near the village Chapala, he documented young fish, but few adults, probably because of th polluted waters near the village. Anyway, the Lago de Chapala belongs to the most endangered lakes in the world with a heavily decreasing watersurface and massive polluted water.

 

Estancia de Igartua IEstancia de Igartua II

 

Manantial La Luz IManantial La Luz II

 

Manantial La Luz IIIManantial La Luz IV

 

Lago de Chapala ILago de Chapala II

 

Los Negritos ILos Negritos II

Colouration: 

  Jordan & Snyder wrote about the colouration in their description: "Color in alcohol light yellowish-olive; 9 short and narrow dark vertical bands on median part of body; the first above base of pectoral; the ninth at base of caudal; scales on dorsal region of body edged with black dots; upper part of head dark; upper half of orbit black; opercles silvery; dorsal fin with a little dusky; other fins without dark color.”

 

  In life, the ground colour is somehow silvery shining. Adults get yellow fin margins, sometimes totally yellowish. Especially the pectoral fins appear often yellow to orange. Adult fish (females?) present a yellow to orange coloured venter.

Biology: 

  Young fish with 9.0mm SL taken from Lago de Chapala on 26 March and a 16mm fish taken on 23 May suggest that the reproduction occurs during spring. Meek (1904) stated that young were born in the latter part of May. He found 21 near-term embryos each 10mm long in a female 68mm long.

Diet: 

  The bifid teeth, the long convoluted gut and 20-28 slender gill rakers suggest it is herbivorous. Nevertheless, some observers documented this species jumping out of the water and catching flying insects in the Lago de Chapala.

Remarks: 

  The whole fish are dried in the sun for food around Lago de Chapala, where this abundant species is taken by commercial fishermen. Hieronimus (1995: pl.4, opposite p.90) recorded the species from the Atlantic Slope in the Río San Juan del Río in Queretaro. I judge this to be another interbasin transfer by human action. Earlier collections at this locality revealed two cyprinids and Goodea atripinnis (as Goodea gracilis Hubbs and Turner).

 

  In France have been selected some albinotic specimens and distributed in the Hobby. As far as we know, these are the only documented albinotic Goodeids.

Photos: 

Image 1: female from La Alberca

Copyright by Thue Grum-Schwensen

Image 2: male from the Lago de Chapala

Copyright by Omar Domínguez Domínguez

Image 3: female from the Lago de Chapala

Copyright by Omar Domínguez Domínguez

Image 4: male

Image 5: female

Images 6 and 7: pair

Image 8: male

Images 9 and 10: females

Images 11 and 12: females, albinotic

Images 13 - 16:male from the Lago de Chapala

Copyright: Anton Lamboj

Images 17 - 20: female from the Lago de Chapala

Copyright: Anton Lamboj

Image 21: male from the Lago de Chapala

Copyright by Wolfgang Gessl (www.pisces.at)

Image 22: female from the Lago de Chapala

Copyright by Wolfgang Gessl (www.pisces.at)

Locations