A morphometric and meristic investigation of Lusitanian toadfish Halobatrachus didactylus (Bloch and Schneider, 1801): evidence of population fragmentation on Portuguese coast*

摘要: SUMMARY: A total of 207 specimens Lusitanian toadfish Halobatrachus didactylus from six different localities were analysed in terms morphometric and meristic characters order to investigate the hypothesis population fragmentation on Portuguese coast. This study confirmed relative isolation between Algarve populations those western estuaries, which also showed a high degree discrimination among them. Morphometric characteristics much more adequate than for good separation these populations. The most relevant H. head width, interorbital width pelvic fin length. These three variables very useful seem play an important role species feeding activity. caudal peduncle development is mainly related specimen’ swimming ability was particularly northern southern estuarine adjacent marine populations, apparently due differences hydrodynamic conditions. Meristic variation mostly latitudinal nature (mainly nasal tentacles pores lower jaw) but some (principally rays counts) water temperature observed.