Skiffia lermae

Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
Skiffia lermae
English Name: 
Olive Skiffia
Mexican Name: 
Tiro olivo
Original Description: 

  MEEK, S. E. (1902): A contribution to the Ichthyology of Mexico. Publication. Field Columbian Museum. No 65, Zoological Series 3 (6): pp 63 - 128

Holotype: 

  Collection-number: Field Columbian Museum, Cat. No. FCM-3616.

  The Holotype has got 54.1mm standard length, collected by S. E. Meek and F. E. Lutz, from 19. to 21.05.1901.

Terra typica: 

  The Holotype comes from the Lago de Pátzcuaro in Michoacán.

Etymology: 

  The species is probably named for the basin of the Río Lerma, where the Lago de Pátzcuaro belongs to, the location, where this species has been discovered.

Synonyms: 

Skiffia variegata   Meek, 1902

Goodea lermae   Regan, 1907

Distribution and ESU's: 

  The Olive Skiffia is endemic to the Mexican federal states of Michoacán, Guanajuato and Querétaro. It was historically reported from the endorheic Río Grande de Morelia basin including the Lago Cuitzeo and the Presa Cointzio, from the Laguna Yuriría and several spring areas (La Mintzita, La Maiza, San Cristobal) draining into the Río Grande de Morelia respectively Lago Cuitzeo. It is furthermore known from the endorheic Laguna Zirahuén and Lago de Pátzcuaro basins, from the Río Angulo drainage including the Lago Zacapú and from habitats along the Middle Río Lerma, at least from a spring near San Francisco del Rincón, Río Turbio drainage and from the Río Laja system. There is one report from this species from the Presa El Centenario near Tequisquiapán, Río San Juán drainage (a Río Pánuco affluent), so it even reached the headwaters of this river. Distribution and abundance of Skiffia lermae have declined steadily over the last 50 years with continued losses through the 2000’s. The species has disappeared from the Laja River, Lake Yuriría, Lake Cuitzeo, and the entire Lake Zirahuén basin, and has become uncommon and limited to a few small springs in the Lake Pátzcuaro and Grande de Morelia River basins (Lyons et al., 1998; Soto-Galera et al., 1998, 1999; De la Vega-Salazar, 2003; Domínguez-Domínguez et al., 2005, 2008; Mercado-Silva et al., 2006). At present, only about six sites remain, the largest of which are in Lake Zacapú in the Lerma River basin, the Molino de Chapultepec Springs in the Lake Pátzcuaro basin, and the La Mintzita Springs in the Grande de Morelia River basin. (Lyons, 2011). According to different drainages, seven subpopulatios are distinguished: The Lago de Pátzcuaro subpopulation (type subpopulation), the Río Grande de Morelia subpopulation, the Río Angulo subpopulation, the Middle Río Lerma subpopulation, the Río San Juán subpopulation, the Laguna Yuriría subpopulation and the Laguna de Zirahuén subpopulation. The last four subpopulations are regarded Extinct. The underlined names are the ones officially used by the Instituto Nacional de Estadística y Geografía; nevertheless, other ones might be more often in use or better known and therefore prefered.

 

  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 Skiffia lermae, we have the possibility to distinguish three ESU's: The first unit Skile1 encompasses populations from the middle Río Lerma, including fish from the Lago de Zacapu, Río Turbio, Río Laja, Río San Juan, Lago de Yuriria and Río Angula. The second ESU - Skile2 - is used for fish from the endorheic Río Grande de Morelia basin, including the Lago de Cuitzeo and several springs like La Mintzita, La Maiza and San Cristobal. ESU number three, Skile3, is in use for the populations from the lakes Pátzcuaro, the type location of the species, and Zirahuén, the type location of the former Skiffia variegata, now a synonym of Skiffia lermae. As it looks like that the latter has to be treated extinct, it is hard to investigate if both really belong to one ESU, so this has to be seen critically.

 

  Maximum Extent of Occurence of Skiffia lermae:

Maximum EOO of Skiffia lermae

Status : 

   International Union for Conservation of Nature (IUCN): not assessed

 

  Conservation status and population trends of Mexican Goodeids (Lyons, 2011): endangered/declining – The historical range of this species encompassed many sites in central Mexico including Lake Zacapu, Lake Yuriria, and the Laja River in the middle Lerma River basin, and the endorheic Lake Pátzcuaro, Lake Zirahuén, and Lake Cuitzeo/Grande de Morelia River basins. Distribution and abundance of S. lermaehave declined steadily over the last 50years, with continued losses through the 2000’s. The species has disappeared from the Laja River, Lake Yuriria, Lake Cuitzeo, and the entire Lake Zirahuén basin, and has become uncommon and limited to a few small springs in the Lake Pátzcuaro and Grande de Morelia River basins (Lyons et al. 1998; Soto-Galera et al. 1998, 1999; de la Vega-Salazar 2003a; Domínguez-Domínguez et al. 2005b, 2008a; Mercado-Silva et al. 2006). At present, about six populations remain, the largest of which are in Lake Zacapu in the Lerma River basin, the Molino de Chapultepec Springs in the Lake Pátzcuaro basin, and the La Mintzita Springs in the Grande de Morelia River basin.

 

  NOM-059-SEMARNAT-2010: Categoría de riesgo (Category of risk): A - Amenazada (threatened)

Habitat: 

  The habitats are quiet waters of lakes, spring-fed ponds, canals and small creeks with clear to turbid water over mud, sand, gravel and decayed organic matter. The vegetation comprises green algae, Eichhornia, Lemna, Scirpus, Salvinia, Nasturtium and Potamogeton. The species prefers usually depths of less than 1m. The currents are none to slow. 

 

Rancho el Molino IRancho el Molino II

 

Rancho el Molino IIIRancho el Molino IV

 

Rancho el Molino VRancho el Molino VI

 

 Manantial La Mintzita II

 

Manantial La Mintzita IV

 

Laguna Zacapu ILaguna Zacapu II

 

Laguna Zacapu IIILaguna Zacapu IV

 

 

Biology: 

Following Miller, the reproductive period lasts from at least February to May, indicated by newborn young or pregnant females taken then. He also documented this species swimming just beneath the surface in full sunlight, the young often in groups of thre to fifteen. 

Diet: 

The gut is - following Pellegrin - long and often convoluted. It is about 3 times the length of the fish. The teeth are mainly bifid in both rows. This species is mainly grazing aufwuchs, for example from submerged Scirpus stems, and algae. It is also attracted by insects at the surface.

Size: 
The maximum known SL is 64mm (Miller et al, 2005).
Colouration: 

The Ground-colour of both sexes is olive. Darker on the dorsal side and brigther on the belly, becoming yellowish to yellow. Females have got several smaller and bigger spots and blotches, giving them a marbled appearance. Males are less marbled, but appear darker than females. A dark vertical stripe on the base of the caudal fin and the ventral part of the caudal peduncle black is often reported. Females may show a dusky lateral band. 

 

Kingston described the colour of males of Skiffia lermae more colourful, with bright orange caudal peduncles and caudal fins and blue-black heads.

 

The Skiffia lermae from Lago de Zacapu is coloured deep yellow without marbles.

 

The variabiliy in this species, like in its congener Skiffia multipunctata seems to be high.

Remarks: 

Meek described in 1902 not only Skiffia lermae from the Pátzcuaro lake, but also Skiffia variegata from the Lago de Zirahuén. Following Meek, it differs from lermae by being more slender and by differences in the colouration. It has been already synonymized by Regan (1906-08), established again by Hubbs & Turner (1939) but finally synonymized by Miller & Fitzsimons in 1971.

 

In the Zacapu-lake lives a yellow population of Skiffia, called Skiffia sp. "Sailfin" or Skiffia sp. "Zacapu". Following O. Domínguez, it differs from lermae not so much, that a separate species has to be described. It is therefore treated as a population of Skiffia lermae.

 

Skiffia lermae differs from multipunctata mainly by its "stretched" caudal peduncle, the smaller dorsal fin, the more slender bodyshape, the smaller size and the colouration, so lermae never shows big black blotches on the sides and is characterized by the typical colouration of the caudal-area in males.

 

In the wild, this species -  like all Skiffia-species, is very rare. Only 4 of the historical 7 reported sites of this species are populated, the biggest populations living in the Laguna Zacapu and the La Mintzita spring in the Lago de Cuitzeo basin.

Locations