title: Habitat segregation and cryptic adaptation of species of Periophthalmus (Gobioidei: Gobiidae).
abstract: A study was conducted on the habitat distribution of four sympatric species of Periophthalmus (the silver-lined mudskipper Periophthalmus argentilineatus, the slender mudskipper Periophthalmus gracilis, the kalolo mudskipper Periophthalmus kalolo and the Malacca mudskipper Periophthalmus malaccensis) from northern Sulawesi. Molecular phylogenetic reconstructions based on one mtDNA marker (16S) were used to validate the morphological taxa, identifying five molecular clades. Periophthalmus argentilineatus includes two molecular species, which are named Periophthalmus argentilineatus clades F and K. Multivariate direct gradient analysis show that these species form three distinct ecological guilds, with the two molecular species occurring in different guilds. Periophthalmus clade F is ecologically eurytypic; Periophthalmus clade K and P. kalolo are prevalent in ecosystems isolated by strong oceanic currents and at shorter distances from the sea; P. gracilis plus P. malaccensis are prevalent in ecosystems connected by shallow coastal waters, in vegetated habitats at larger distances from the sea. This indicates for the first time that mudskipper species exhibit a range of adaptations to semiterrestrialism not only within genera, but even within morphospecies, delineating a much more complex adaptive scenario than previously assumed.
authors.affiliation: Environmental and Life Sciences Programme, Universiti Brunei Darussalam, BE1410 Bandar Seri Begawan, Brunei Darussalam.|Institute of Biological Sciences, Institute of Ocean and Earth Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
authors.forename: G
authors.initials: G
authors.lastname: Polgar
authors.affiliation: Department of Theoretical and Applied Sciences, University of Insubria, 21100, Varese, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Zaccara
authors.affiliation: Department of Comparative Biomedicine and Food Safety, University of Padova, 35020, Legnaro (PD), Italy.
authors.forename: M
authors.initials: M
authors.lastname: Babbucci
authors.affiliation: Department of Theoretical and Applied Sciences, University of Insubria, 21100, Varese, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Fonzi
authors.affiliation: Department of Theoretical and Applied Sciences, University of Insubria, 21100, Varese, Italy.
authors.forename: C M
authors.initials: CM
authors.lastname: Antognazza
authors.affiliation: Environmental and Life Sciences Programme, Universiti Brunei Darussalam, BE1410 Bandar Seri Begawan, Brunei Darussalam.
authors.forename: N
authors.initials: N
authors.lastname: Ishak
authors.affiliation: Environmental and Life Sciences Programme, Universiti Brunei Darussalam, BE1410 Bandar Seri Begawan, Brunei Darussalam.|Universiti Teknologi Brunei, Jalan Tungku, BE1410 Bandar Seri Begawan, Brunei Darussalam.
authors.forename: Z
authors.initials: Z
authors.lastname: Sulaiman
authors.affiliation: Department of Theoretical and Applied Sciences, University of Insubria, 21100, Varese, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Crosa
mesh_terms: D000064:Acclimatization; D000222:Adaptation, Physiological; D000818:Animals; D004272:DNA, Mitochondrial / Q000235:genetics; D017753:Ecosystem; D007214:Indonesia; D015999:Multivariate Analysis; D009792:Oceans and Seas; D010473:Perciformes / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D060047:Reproductive Isolation; D013045:Species Specificity; D014872:Water Movements
chemical_list: D004272:DNA, Mitochondrial
keywords: amphibious fishes; coastal wetlands; hidden variation; intertidal gradients; molecular taxonomy