Valencia hispanica (Valenciennes 1846)
Synonims:
Fundulus hispanicus, Hydrargira hispanica (Valenciennes, 1846).
Common and Vernacular names:
Samarugo
(es), Samaruch (val), Samaruc (lev), Spanish Tooth Carp (eng), Valenciakärpfling
(al).
Description: Oblong body,
proportionally thin, somewhat depressed in cephalic region and laterally
compressed the rest, fins with rounded border, supraterminal mouth with one-apex
teeth, irregularly disposed in several rows. Relatively big scales. Brown
greenish colour on top becoming lighter towards the lower part of the body.
Males have green blue glints, and show a dark spot behind the operculus and some
brownish narrow vertical bars. Odd fins have small
yellow-orange colour and have spots on the rays. Females are tender in colour
and their dorsal and anal fins are shorter than in males. Longitudinal lie with
28 to 30 scales and transversal line with only 8 or 9.
Meristic formula:
D. 10-11; A. 12-14; P. 15; V. 6; C. 18.
Size: They may reach more
than eight centimetres, being females usually larger than males of their same
age. Usual size in males varies between four and seven cm.
Habitat: Inside their distribution
range, they live in slow flowing or stagnant waters, which must be clean,
transparent and with abundant aquatic vegetation. Nowadays it is only found in a
few springs "ullals" and in the influence zone of these. It
used to live in irrigation channels, near the shores of littoral lagoons and
even in the middle zone of some Mediterranean rivers (Serpis, Verde, Júcar...).
In laboratory conditions it can endure highly saline water (Sanz, 1985) it is
rarely found in these conditions in nature, being a characteristic fish of sweet
water and not form marshes and brackish waters as the other Iberian
cyprinodontids.
You can see a habitat photo selection in our
"Imágenes / Images".
Geographical distribution: Very
restricted in present time. Although there is a very dubious quotation in
Colliure (Arnoult, 1957), in historical time it used to live along the
Mediterranean coast, form Northern Catalonia, Aiguamolls de l´Empordá (San
Miguel, 1979) to the North of Alicante. Nowadays there are only three
populations that still survive: Near Peñíscola (Castellón), around the Albufera
in Valencia and in Pego-Oliva (Valencia-Alicante). Quotes of samaruc in the
Southeast of the Iberian Peninsula and in the Balkans correspond to other
species (Fundulus heteroclitus and Valencia letournexi). The origin of some
individuals labelled as coming from Mar Menor (Murcia) is
also very dubious, they are kept in the National Museum of Nature Sciences (see
Doadrio, I. 1989).
Habits and Feeding:
Little is known about biological characteristics of this species in the wild,
what is known comes from captive research. Adults may swim in small groups, that
are not too coherent, males are territorial during the mating season. Young fish
live next to the surface, hiding among vegetation. They have a very
characteristic way of moving, alternating between quick and short displacements
and sudden stops. Their basic diet is composed of small aquatic invertebrates,
mainly insects and their larvae, although they also catch terrestrial insects
that fall on the water.
Breeding: It usually happens from
April till October. It seems that there are two peaks in their sexual activity,
the first of them at the beginning of Spring and the second one at the end of
the Summer. As usual, the main factors that trigger reproductive behaviour are
temperature (over 17 ºC) and day length (over 11 hours). During this time of the
year males show a more colourful pattern, and defend small territories from
other rival males. Their ritual fights include a full extension of extension of
all fins and a dilation of the branchiostegal membrane. When a mature female is
ready and makes contact with one of these territorial males, there is a nuptial
dance that consists of semicircular displacements of the male and spasmodic
lateral movements of his head. Eggs are laid when both fish approach an adequate
substrate such as feather-like leaves of aquatic plants,
filamentous algae, etc. They approach their anus and shivering lay a few
relatively big eggs (2-2,5 mm in diameter) that stick to the substrate by way of
filaments. From laying till hatching there is little more than one week at
normal water temperature this season.
Other comments: This species may
hybridise with others from the same Genus (Gómez, F. 1995) coming from Albania
and occidental Greece, Valencia letournexi, although it seems that the resultant
individuals are not fertile. Theoretical calculations indicate that the gap
between these two species is around 18 million years (Perdices, A. et al. 1996).
Interest: It is a very
endangered Iberian endemism, that figures in a list published by the IUCN as one
of the 24 most endangered vertebrate species in the World. All the factors that
affect this specie's nowadays conservation have a human origin, such as aquatic
pollution of different sources (agricultural, urban and industrial), habitat
destruction (waterland desiccation, case hardening of irrigation channels and
other physical alterations), introduction of exotic species either predators
(black bass, Pike-perch, sun fish) or competitors (Gambusia). There is also
another factor, their distribution area is in one of
Europe's most populated areas, with big demand on hydric resources during the
whole year, which is even bigger during the summer due to the enormous tourists
affluence.
Protection and present status:
Directive 92/43/CE 21st May 1992, about conservation of natural habitats and
wild flora and fauna: Annex II (fauna of special interest) and IV (requires
strict protection)and "prioritary" in both of them. National Catalogue of
Endangered Species (R.D. 439/1990. BOE 5/4/90) "in danger of extinction". D.
21/7/86 of the Valencian Community "protected species". D. 265/1994 which
creates and regulates the Valencian Catalogue of fauna endangered species:
"endangered of extinction". Protected in Catalonia in the DOGC nº 493
12/12/1984: "protected species".
(*) "La Pletera": Lagunas en L'Estartit (Girona)
