Recently, the Manchester Museum has acquired specimens of two interesting species of subterranean fishes from our Honorary Academic Curator, Dr Graham Proudlove. Specimens of both species originated from captive-bred populations that are kept in research labs in Germany in order to study their biology and genetics. Graham kindly shared some information about both fish species with the readers of our blog, see below.
Garra andruzzii (Vinciguerra, 1924)
They are entirely subterranean and live, not in caves as such, but in a groundwater aquifer which is accessed only via wells. This species is one of the most cave adapted in the world (the technical term is troglomorphic) and has is entirely without eyes or body pigment (Fig. 1). It has been studies extensively and there is at least one breeding captive population, possibly two. The fishes donated to the Manchester Museum were originally destined for a research group in the Department of Zoology at Oxford University. This group work on the behaviour of fishes and so obtained permission to start a breeding population in Oxford. Clearly living fishes were required for this and so someone was dispatched by plane to Germany to obtain the necessary animals. Unfortunately this particular migration was not terribly successful (like many other of course) and all fourteen fishes were dead on arrival in Oxford. Graham Proudlove happened to visit at around this time and once he had heard this asked if they wanted the specimens. As dead specimens were of no use for behavioural biologists, Graham was presented with the lot of them.
Fourteen of these specimens are now in the Manchester Museum (accession numbers: D1293.1-2), and are available for examination and research upon request from the Curator of Zoology.
A full account on this interesting fish species can be found in the illustrated World Catalogue of Subterranean Fishes compiled by G. Proudlove.
Shortfin Molly, Poecilia mexicana Steindachner, 1863
This species is a very common surface (epigean) fish throughout Central America (Fig. 2). At two sites in the State of Tabasco, Mexico, the Cueva del Azufre and Luna Azufre (17o27’N, 92o46’W) there are permanent cave populations which exhibit signs of cave adaptations. The caves are very unusual in having high concentrations of toxic hydrogen sulphide gas and the habitat is considered to be extreme. The fishes are thus known as extremophiles and have been extensively and intensively studied over many years by a research group which originated at the University of Hamburg. The numerous members of this group have migrated to many parts of the world over the years but continued to spend much time researching with this species. The cave is home to other remarkable animals including a very large homopteran bug which make many a meal of these small fishes.
A full account on this interesting fish species can be found in the illustrated World Catalogue of Subterranean Fishes compiled by G. Proudlove. More information about Shortfin Molly can be found here and here.
The Manchester Museum has 15 males and 18 females of Shortfin Molly (Poecilia mexicana) in its collection (accession numbers: D1293.3-8), which are available for examination and research upon request from the Curator of Zoology.
The Manchester Museum cordially thanks Dr Graham Prodlove for his valuable donation our zoology collections and for providing accounts on both fish species.