ECQIAOY, SYSTEMATICS AND EVOLUTION OF AUSTRALIAN FBWS 67
Other ccmmon food items are Diptera (Chlicidae, Simuliidae), Coleopbra, Ccllembola, snd snails of the two genera Bdhriembym and
LuidL+ms. Once again thew are the commoneat prey species in the
places whare the frogs are found. Lee (1967) found Hymenopbre and
Coleopters to be the commonest items in the diet of HeZewpma species.
Spiders have been found aa food items in Crinia georgiana, Olauertia
rwselli, Heleiopma species and Cyclorana cultripes. Items which are
infrequently found as food are: Grasshoppers, earwigs, Isopod Cruetacea
(AmnidiZZidacea) and mites (Acarina). In general frogs appear to be
unspecirtlised opportunistic predators (Main and Calaby, 1967; Lee,
1967). Myobatruchus remains in the vicinity of termitaria and feeds
when it burrows into the galleries. It is the only frog with specialid
feeding Habits found in Australia (Calaby, 1966, 1960).
G. SPECIES INTERSPERSION
1. Regional replacement
In a general way the distribution and interspersion of species can be
thought of as the most readily observed indication of ecological differences between species. Frequently, groups of species will be found
aesociated together in one region while other groups of species are
aasociatd in different regions. For example the association of species
of Heleioporus and a species of Crinia which is common in southern and
south-xwstern Australia is replaced to the east by an emciation of
Neobatrachua species and Pseudopkryne occidentalis and to the north
by Cycioram species, Lirnnodynastes spenceri and Qkuertia russelli.
Such regional replacements can be explained in terms of the type of
rainfall required for breeding; Heleioponca and Crinia require winter
rain, the others summer rain. However, the different ranges occupied
by the Neobdrachw and Pseudophryne on the one hand and Cyclurana,
Limnodgmtes and alauertia on the other, seem to be related to the
conditions of the physical environment which can be tolerated by the
two rtsscciations. What is thought to be the significant factor is illustrated by the following field example.
Travelling northward in the vicinity of Menzies, one pasees abruptly
from the range exclusively occupied by Neohtmhus species to that
occupied by Cyclorana platycepicalus and Limno&ynastes epenceri. Species of Neobatrachw are occaaionally found within the range of Cycloram sp. and L. spenceri, but are always rare and in very low numbers,
e.g. N . &or at Jigalong (Lindgren, 1960; Lindgren and Main, 1961).
A consistant observation in this case is that where Neobatrachus is the
only genus, the vegetation is halophytic. When Cychana pEatycepcalus,
C. cuztripea and Limnodynaetes spenceri are found, the vegetation ia
Other ccmmon food items are Diptera (Chlicidae, Simuliidae), Coleopbra, Ccllembola, snd snails of the two genera Bdhriembym and
LuidL+ms. Once again thew are the commoneat prey species in the
places whare the frogs are found. Lee (1967) found Hymenopbre and
Coleopters to be the commonest items in the diet of HeZewpma species.
Spiders have been found aa food items in Crinia georgiana, Olauertia
rwselli, Heleiopma species and Cyclorana cultripes. Items which are
infrequently found as food are: Grasshoppers, earwigs, Isopod Cruetacea
(AmnidiZZidacea) and mites (Acarina). In general frogs appear to be
unspecirtlised opportunistic predators (Main and Calaby, 1967; Lee,
1967). Myobatruchus remains in the vicinity of termitaria and feeds
when it burrows into the galleries. It is the only frog with specialid
feeding Habits found in Australia (Calaby, 1966, 1960).
G. SPECIES INTERSPERSION
1. Regional replacement
In a general way the distribution and interspersion of species can be
thought of as the most readily observed indication of ecological differences between species. Frequently, groups of species will be found
aesociated together in one region while other groups of species are
aasociatd in different regions. For example the association of species
of Heleioporus and a species of Crinia which is common in southern and
south-xwstern Australia is replaced to the east by an emciation of
Neobatrachua species and Pseudopkryne occidentalis and to the north
by Cycioram species, Lirnnodynastes spenceri and Qkuertia russelli.
Such regional replacements can be explained in terms of the type of
rainfall required for breeding; Heleioponca and Crinia require winter
rain, the others summer rain. However, the different ranges occupied
by the Neobdrachw and Pseudophryne on the one hand and Cyclurana,
Limnodgmtes and alauertia on the other, seem to be related to the
conditions of the physical environment which can be tolerated by the
two rtsscciations. What is thought to be the significant factor is illustrated by the following field example.
Travelling northward in the vicinity of Menzies, one pasees abruptly
from the range exclusively occupied by Neohtmhus species to that
occupied by Cyclorana platycepicalus and Limno&ynastes epenceri. Species of Neobatrachw are occaaionally found within the range of Cycloram sp. and L. spenceri, but are always rare and in very low numbers,
e.g. N . &or at Jigalong (Lindgren, 1960; Lindgren and Main, 1961).
A consistant observation in this case is that where Neobatrachus is the
only genus, the vegetation is halophytic. When Cychana pEatycepcalus,
C. cuztripea and Limnodynaetes spenceri are found, the vegetation ia