Surface activity in the mudskipper,<i>Periophthalmus waltoni</i>Koumans 1941 in relation to prey activity and environmental factors

The potential feeding advantages that are offered to the barred mudskipper Periophthalmus argentilineatus by its amphibious life-style were investigated. To this end the feeding ecology of these fish, the position they occupy in the mangrove food web and the importance of different morphological factors for their diet were studied. Analysis of gut contents showed that the major component of the barred mudskipper diet changes during growth from small crustaceans (e.g. copepods and amphipods) to polychaetes to mangrove crabs. This dietary shift was found to be facilitated through enlargement of the mouth, as well as elongation of the gut. The use of stable isotope analysis revealed that barred mudskippers had a similar trophic position as other zoobenthivore fish species, but that their diet did not appear to be affected by competition for food with other zoobenthivores. The amphibious habits of the barred mudskipper provide specific advantages to its feeding ecology, such as access to an abundant food source of mangrove crabs, which are mostly inaccessible for other fish species.

Section: Discussionmentioning

confidence: 79%

Influence of morphology and amphibious life‐style on the feeding ecology of the mudskipper Periophthalmus argentilineatus

Kruitwagen

Nagelkerken

Lugendo

et al. 2007

“…g . Periophthalmus waltoni Koumans 1941; Clayton & Snowden, ). It appears unlikely that the moderate seasonal changes in rainfall in the study area can significantly affect the observed interspecific habitat segregation, at the spatial scales of the measured environmental variables.…”

Section: Discussionmentioning

confidence: 99%

“…Species of Periophthalmus living in semi-arid climates are known to perform seasonal migrations to wetter areas during dry periods (e.g. Periophthalmus waltoni Koumans 1941;Clayton & Snowden, 2000). It appears unlikely that the moderate seasonal changes in rainfall in the study area can significantly affect the observed interspecific habitat segregation, at the spatial scales of the measured environmental variables.…”

Section: H a B I Tat S E G R E G At I O Nmentioning

confidence: 91%

Habitat segregation and cryptic adaptation of species ofPeriophthalmus(Gobioidei: Gobiidae)

Polgar

Zaccara

Babbucci

et al. 2017

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.

“…Observations were always made on the exposed substratum and under different tidal conditions: (1) ±2 h around predicted and observed low tide or, when visible, at a distance of >10 m from the water's edge (low tide): under these conditions, the fish distribution was assumed to be unaffected by water movement, and (2) near the water's edge, during flood and ebb tides. No data were collected when a plot was influenced by rain or wind (Clayton & Snowden, 2000).…”

Section: Methodsmentioning

confidence: 99%

Differentiation and adaptive radiation of amphibious gobies (Gobiidae: Oxudercinae) in semi‐terrestrial habitats

Polgar

Sacchetti

Galli

2010

During several surveys made in the region of the lower Fly River and delta, Papua New Guinea, nine species of oxudercine gobies (Gobiidae: Oxudercinae) were recorded: Boleophthalmus caeruleomaculatus, Oxuderces wirzi, Periophthalmodon freycineti, Periophthalmus darwini, Periophthalmus novaeguineaensis, Periophthalmus takita, Periophthalmus weberi, Scartelaos histophorus and Zappa confluentus. An exploratory multivariate analysis of their habitat conditions discriminated five guilds, differentially distributed in habitats with different quantities of environmental water and three guilds corresponding to different levels of salinity. A partial correspondence between phylogenetic and ecological categories suggested the presence of parallel adaptive radiations within different genera. In particular, the species found in the most terrestrial habitats (P. weberi) was also found in the widest range of conditions, suggesting that colonization of extreme semi-terrestrial and freshwater habitats by this species was facilitated by eurytypy. It is proposed that these findings provide insight into convergent adaptations for the vertebrate eco-evolutionary transition from sea to land.