Skiffia francesae

Colouration: 

  Males are bright gold with superimposed gray cast, especially intense in courting. Courting males show gray borders on the dorsal, anal and caudal fins and gray pelvic fins. There is a black crescent present at the base of the caudal peduncle. In non-courting males, the gold colouration is most evident in the dorsal, anal and caudal fins and faintly present along the caudal peduncle. Some scattered, small gray spots may occur at the base of the caudal fin and on the dorsal fin. Females and juveniles are gray-green with scattered small black flecks along the lateral scale row and the dorsal surface. The fins are clear. The base of the caudal peduncle has got a small black crescent.

  Looking on the original habitats of Skiffia francesae, they suggest the species may prefer partly dense vegetation and roots (in the aquarium even dense artificial staff) to hide, but also open water areas to display. In the wild, there was little or none current to observe in the former biotops, so it won't be necessary in the aquarium as well. In the aquarium, the fish sometimes hide deep in the shelter, but courting and impressing as well as fighting males can often be seen in the open water. Fry is usually not eaten, so it is easy to build up a flock breeding colony.

 

  The recommended tank size is at least 60 liters, bigger ones are better for sure. Dense vegetation combined with few roots, wood or stems of reed and free space areas for the males to impose and fight make sense. The current should be low.

 

  In the wild, this species fed from algae, aufwuchs and small invertebrates. Kingston observed Skiffia francesae  at the type location grazing on vertical stems of reed (1978). In the aquarium, the food could be composed of different small frozen or freeze dried invertebrates (DaphniaArtemia), small livefood (e.g. Nauplia, CyclopsDaphnia) and good flake food or tablets respectively tiny granulat food. However, the main source should be vegetarious, mainly algae. A good solution to produce algae-sticks is to place stems of reed in a vase of water in front of the window and add some pond water. After a few days, you will get vertical structures covered with aufwuchs and algae, which is perfect for Skiffia francesae. Fix it with one end on a heavy structure to place the vertical floating stems into the water. It is very nice looking on a group feeding from that source. Other components may be food tablets for Loricarids or Shrimps.

 

  This species never attacks other fish, but may be superimposed by others easily (like Platys did in the wild). On the other hand, a fertile group of Skiffia francesae could be a problem for other species to reach food, so this species does better in its own tank.

 

  Concerning water quality, this species is in need of greater water changes (60 - 80% every week), 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 burn themselves out. So, mainly 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 gets too warm (25°C?).

 

  This species does 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.

Etymology: 

   The species was named by Kingston for Frances H. Miller, in recognition of her help in furthering our understanding of Mexican fishes.

First Describer: 
Kingston, 1978
Mexican Name: 
Tiro dorado
Habitat: 

  The former habitat was a quiet, thermal and clear to murky water with only a slight current. Substrate is deep mud with a few rocks, silt and sand. A few species of aquatic plants were present, comprising EichhorniaPistia, Ceratophyllum and Potamogeton. The Golden Skiffia prefered depths of less than 0.5m. Miller and Fitzsimons measured watertemperatures between 24 and 26°C (February 1976). The water was heavily polluted. A survey in 2016 revealed, that the habitat hasn't altered significantly since the 1970's, for the only thing, that most of the fish species have gone since that time.

 

  The Molino spring near Cuyacapán possesses clear water, the rim structured with roots of different trees (mainly Ficus) and reed areas. The substrate is similar to the former habitat in Teuchitlán. A survey in 2016 revealed only young specimens of Lepomis and Micropterus, but no Goodeids.  

 

Cuyacapán spring ICuyacapán spring II

 

Cuyacapán spring IIICuyacapán spring IV

 

Río Teuchitlán IRío Teuchitlán II

 

Río Teuchitlán IIIRío Teuchitlán IV

 

Balneario El Rincón, Río Teuchitlán IBalneario El Rincón, Río Teuchitlán II

Distribution and ESU's: 

  This species was originally only known from the Río Ameca basin in Jalisco, but in 2006, a secound population in the El Molino spring near Cuyacapán in the valley of the endorheic (and nearly completely dry) Sayula lake was discovered, now also extinct in the wild.

 

  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.

 

  We recoginze two ESU's within Skiffia francesae: Skifr1 is in use for fish from the Río Ameca basin, in fact, for the only population in culture from the type location from the Río Teuchitlán. On the other hand, there is only one single population known from the Sayula valley. For this population, we have chosen Skifr2

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 Skiffia francesae, following Uyeno, Miller & Fitzsimons, 1983:

2n = 48    2m/ 6sm/ 40stt

Status following other sources: 

  Status: Extinct

  Comment: Captive populations exist

Images: 
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Remarks: 

  Skiffia francesae is very closely related to Skiffia multipunctata, and sometimes thought to belong to this species as there is genetically nearly no difference. However, there are little differences in the body-shape, the size and the colouration, so it is still treated as a separate species. 

 

  Kingston (in the original description 1978) designated Skiffia francesae as a dwarf-species, evolved from Skiffia multipunctata.


  This species lived in the Río Teuchitlán and disappeared from this river by competition through Xiphophorus maculatus, pollution and fragmentation and modification of the springs into a water recreation area. The Río Teuchitlán, former resembling a paradisiac river, is nearly completely altered and many former species have gone. This situation has been the driving force for Ivan Dibble (who loved that river) to start the Mexico Fish Ark Project to rescue endangered fish in Mexico.

 

  In 2006, a colourful Skiffia has been found in the Sayula-valley (El Molino spring at Cuyacapán). From size and colouration, it resembles very close francesae. Phylogenetically, it ranges between francesae and multipunctata, being definitely closer to francesae (however, even multipunctata is very close to francesae). It probably belongs indeed to Skiffa francesae, following Dominguez (pers. comm. 2011). In 2011, the spring dried out and so even this population is extinct in the wild. Now, it is filled up with water again, but contains only predators. A second spring close by revealed at least the also thought to be extincted Zoogoneticus purhepechus and Poeciliopsis infans, but none of the other native fish ("Xenotoca" cf. melanosoma, Skiffia francesae, Ameca splendens

Terra typica: 

  The Holotype was collected in the Río Teuchitlán, below and just E of Teuchitlán, near the road between HW 70 and Etzatlán in Jalisco.

Synonyms: 

  none

Size: 
The maximum known SL is 43mm
Status after IUCN: 

  Extinct in the wild

Diet: 

  The gut is about two to three times the length of the fish. Kingston documented the content, mainly pennate diatoms, some (probably Ulotrichales et al.) filamentous algae, one small snail and a few pollen grains. The teeth are mainly bifid in both rows. This species is a vegetarian and definitively grazing aufwuchs and algae on vertical structures. Another indication for this feeding behaviour are the upturned lips and the wedge-shaped head.

English Name: 
Golden Skiffia

Locations

Biology: 

  Kingston documented fourteen broods from a wild caught fish. The mean number of young per brood has been nine, with a range from five to fifteen. The size of the newborn ranged from 8.5 to 10.7mm SL (based on three broods).

Holotype: 

  Collection-number: University of Michigan Museum of Zoology, Cat. No. UMMZ-201177.

  The Holotype is an adult male of 29.5mm standard length, collected by R. R. Miller and J. M. Fitzsimons, 22.02.1970.

Original Description: 

  KINGSTON, D. I. (1978): Skiffia francesae, a new Species of Goodeid Fish from Western México. Copeia (3): pp 503 - 508