FAUNA AND FLORA O F MANGROVE SWAMPS
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from a level close to the seaward fringe upwards almost to the level
reached by high water of ordinary spring tides. At Benut and other
FIG. 61. Periophthalmus ?kalolo. Twin turrets of nest burrow at Quissanga, July 1'367.
places near Singapore and in Malaya, in Borneo and in Queensland,
mud-skippers of the kalolo group occur mainly in the middle and
upper parts of this range, As the tide rises they skitter over the surface
of the water from refuge to refuge but rarely climb trees in the fashion
of P. chrysospilos, although they may perch, nightjar fashion, along a
branch just at or slightly above water level, or embrace a twig or root
using the pectoral fins as " arms ".
P. chrysospilos does not stray far from its " home " in the seaward
avicennia and sonneratia fringes. As the tide rises the fishes climb into
the trees and cling to the branches with the sucker formed by the fused
pelvic fins. They climb up just in front of the advancing water and
often keep the tail just under the surface. It is no doubt this habit