Allodontichthys tamazulae

Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Allodontichthys tamazulae
Original Description: 

  TURNER, C. L. (1946): A contribution to the Taxonomy and Zoogeography of the Goodeid Fishes. Occasional Papers of the Museum of Zoology University Michigan No. 495: pp 1-15

Etymology: 

  The species is named for the town of Tamazula de Giordano in the state of Jalisco.

Holotype: 

  Collection-number: University of Michigan Museum of Zoology, Cat. No. UMMZ-143022.

  The Holotype is an adult female of 27mm standard length, collected by C. L. Turner, 03.04.1939.

English Name: 
Peppered Splifin
Mexican Name: 
Mexclapique de Tamazula
Synonyms: 

  none

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 Allodontichthys tamazulae, following Uyeno, Miller & Fitzsimons, 1983:

2n = 48    2m/ 2sm/ 44stt  

Size: 
The maximum known standard length is 73mm (Miller et al, 2005).
Terra typica: 

  The Holotype was collected in the Río Tamazula, a tributary of the Río Tuxpán, just above the town of Tamazula de Giordano in Jalisco.

Status after IUCN: 

  not assessed

Status following other sources: 

  Status: Vulnerable

  Population development: Stable since 2000

Distribution and ESU's: 

  The Peppered Splitfin is endemic to the Río Tuxpán and its tributaries. All the rivers are part of the upper Río Coahuayana basin in Jalisco.

 

  ESU ist short for Evolutionarily Significant Unit. Each unit expresses an isolated population with different genetic characteristics within one species.  ESU's can be defined by Molecular genetics, Morphology and/or Zoogeography and help in indicating different phylogenetic lineages within a species. The abbreviation for an ESU is composed of the first 3 letters of the genus, followed by the first 2 letters of the species name and an ongoing number in each species.

 

  In Allodontichthys tamazulae, it is not possible to distinguish different ESU's, so there is only one recognized: Aldta1

Habitat: 

  The habitats are generally small, rocky streams and riffles over substrates of sand, rocks and boulders. The vegetation is typically green algae, sometimes sparse or none, especially in large rivers where the species is scarce. The currents are slight or moderate to swift, the water is turbid or clear. It can be found in depths of 1m, but usually it prefers depths of 0.5m or less. Like all known Allodontichthys - species, the Peppered Splitfin is a bottom - dwelling and riffle - inhabitating species. As expected from this behaviour, Miller & Uyeno found a considerably smaller swimbladder than in the genus Ilyodon. It extends only to between the fourth and fifth rib (to the first in Ilyodon). Its habitats are similar to those of the North American darters (Percidae, tribe Etheostomatini) living among and under rocks in shallow waters.

 

  On a survey in 2016, a group of members of the GWG found this species together with Allodontichthys hubbsi and Ilyodon whitei close to the bridge at Contla in the Río or Arroyo Contla in very shallow (about 20cm deep) water in swift current. Both Allodontichthys species were easy to catch by lifting rocks, were the fish hided and put a handnet over the place. The river had a width of about three to four meters in this dry season, the broad stony river bank sugested a width of about eight to ten meters in the rainy season. The survey revealed good stocks of this species with nearly the same number of individuals as of the Whitepatch Splitfin. We were able to find this fish additionally in the Río Tamazula at the east end of the town of Tamazula de Giordano, together with the same species of Goodeids and "Xenotoca" lyonsi in sligthly deeper water and swift current.

 

  The Peppered Splitfin shares habitats with its congener Allodontichthys hubbsi in the headwaters of the Río Tuxpán, but in the warmer and a bit slower running parts of the river, it may be the only representative of the genus.

Puente ContlaArroyo Contla

Río Tamazula I

Río Tamazula II

 

Río Tamazula III

Río Tamazula IV

Colouration: 

  Turner pictured to colouration of preserved specimens in the following way: "In general the colouration of A. tamazulae is much lighter than of A. zonistius, and the entire portion above the lateral line is more lightly mottled with dark brown. About 12 heavy, dark, vertical bars extend in the females of A. zonistius from well above the lateral line to well below the lateral line, and a black comma - shaped patch is present just back of the pectoral fin. In A. tamazulae there are 18 to 22 very short dark bars along the lateral line. Only in the part anterior to the dorsal fin and behind the head is there any considerable extension of the bars below the lateral line. In this area 7 to 10 irregular bars extend downward upon the belly. The comma - shaped patch behind the pectoral fin is present in A. tamazulae, but is much lighter than it is in zonistius. Three light vertical bars occur upon the caudal fin in A. tamazulae. There are none in A. zonistius. All males are more heavily marked than the females, particularly in the vertical bars below the lateral line upon the belly."

Biology: 

  Turner found no gravid females in April 1946. Miller took individuals of 14 – 18mm SL between 24. February and 24. April. This suggests a reproduction during the early winter.

Diet: 

  The conical and shouldered teeth and the short gut (two - thirds to three - fourths) indicate carnivorous feeding habits. Turner found some large (5mm) insect larvae in the gut.

Remarks: 

  In the 1980s, Miller & Uyeno postulated, that Allodontichthys hubbsi and tamazulae might be sister taxa, because they are distributed sympatric and are of similar shape. In contrary, the phylogenetic analyses of Shane Webb in 2002 supported that Allodontichthys hubbsi is the most primitive member of the genus and not a sister-species to the sympatric distributed Allodontichthys tamazulae. The closest relative to Allodontichthys tamazulae might be Allodontichthys zonistius. 

 

  Webb examined two populations of Allodontichthys tamazulae, one Aquarium strain from the Río Tamazula and one wild caught one from Puente Contla, also from the Río Tamazula. Surprisingly he found notably differences of the 2 samples (2.1% sequence divergence). That is nearly as much as he found between polylepis and the clade zonistius plus tamazulae (2.4%).

 

  The species is still quite abundant at the type locality just above the town of Tamazula, but can't be found downstream of the town, probably due to pollution. Allodontichthys tamazulae is more widespread and numerous in the Río Tamazula and Tuxpan than its congener hubbsi.

 

  De Jong reported about specimens of a length of 100mm. This may be in correlation with tank-raised conditions and a longer life in captivity.

Husbandry: 

  Looking on the biotopes of Allodontichthys tamazulae, they suggest the species may prefer a habitat with moderate to swift current, structured with gravel, rocks and boulders. It seems to be less aggressive than its congeners, nevertheless there is aggression between the adult fish, so the tank set up should prevent the fish from seeing each other most of the time. Fry is eaten in most of the cases, but it may depend on the quantity and quality of food and on the number of space to hide. When several different stages of juveniles occur, fry may be neglected, so it makes sense to add separate brought up fry to the group with a size of 1.5 or 2cm to provide these stages and get a flock breeding colony.  

 

  The recommended tank size is at least 150 liters, bigger ones with a generous base and little height (25cm are enough) are better for sure. With rocks well structured tanks combined with some roots and/ or wood seem to do best with this species. The current should be moderate or swift. 

 

  In the wild, the species seem to feed from small or middle - sized invertebrates like bloodworms or insect larvae, so feeding with similar food, Daphnia, Mysis and other food from animalistic sources will be best for this predatory fish.  

 

  Concerning water quality, this species is in need of greater water changes (60 - 80% every week) like most of the Goodeids, especially river inhabiting species, so an automatic water changing system can be helpful. Otherwise, in combination with constant temperatures higher than 24°C, fish may get sick, lose resistance against diseases and age too fast. So for keeping the strain healthy and strong, give the fish a rest during winter time with temperatures lower than 20°C for 2 or 3 months so they stop producing fry. In spring, when the temperature slowly increases, they will start spawning at 20 or 21°C and won't stop until it gets colder again or when it gets too warm (25°C?).

 

 This species is doing very well when is kept in the open from spring to fall, starting when the temperature exceeds 15°C water temperature and cold periods are no longer expected. During the warm summer, reproduction will stop and may occur again in fall. Bring the fish in before the temperature goes below 10°C water temperature and keep them cool for the first days, then slowly raise the temperature but try to stay below 20°C over the winter time.