A karyological study on four species of Mediterranean gobiid fishes.

Karyotypical studies on Dormitator maculatus Bloch and Gobiomorus dormitor Lacepede (Gobiidae: Perciformes)

“…In the case of D. maculatus, the chromosomal rearrangements involved must have been many more, at least one centric fusion and 21 pericentric inversions. Sexual chromosomal dimorphism has been reported for three gobiid species: for Mogrunda obscura by Nogusa (1955) in his pioneer work on gobiid cytogenetics , f or Gobiodon citrinus by Arai and Sawada (1974) and for Gobius paganellus and G. niger by Thode et al (1983). However, in this investigation no heterochromo -somes nor heteropicnotic bodies were detected.…”

“…So, while they have been found in Mogrunda obscura, they have not in Mogrunda mogrunda et al 1974). Similarly no sex-chromosomes were found in Gobius abei (Lieder 1964), G. cobitis nor G. falax (Thode et al 1983). The existence of sex-chromo somes represents a derived, exceptional condition in fishes and its appearance in different lineages seems to indicate a recurrent evolutionary trend worth further investigation, since the congeneric species of those with sex-chromosomes might have attained intermediate steps in evolutionary pathways leading to the differ entiation into sex-chromosomes.…”

Multiple Chromosome Polymorphism in Gobius paganellus (Teleostei, Perciformes)

“…The systematics of this group, based on conventional criteria, has been rather debatable and has given rise to a prolific synonymy especially noticeable in G. paganellus (Hureau and Monod, 1973). Moreover chromosome numbers given by other authors for this species (Cataudella et a!., 1973;Colombera and Rasotto, 1982) disagree with that previously reported by us (Thode et a!., 1983). These discrepancies have led us to undertake an extensive study in order to clarify the situation in this species.…”

“…46 specimens of both sexes of G. paganellus from a single population were collected in the south Mediterranean coast during 1982 and1983. Conventional mitotic and meiotic analyses were carried out on cells from spleen, kidney and testis using the technique of Capanna et a!. (1972), slightly modified by Alvarez et a!.…”

Karyotype ofCarapusacus(Brünnich, 1768) (Pisces, Carapidae)

“…It is currently held by numerous authors (OHNO et al 1969;EBEUNG and CHEN 1970;OHNO 1970;THODE et al 1983;VITTURI et al 1984) that 48 acrocentric chromosomes constitute the ancestral complement in teleostean fishes. The consequence is that chromosome sets which differ in the number and/or morphology from the primitive one, are to be considered as derived conditions.…”