ECOLOGY, SYSTEMATICS A N D EVOLUTION OF AUSTRALIAN FROGS 67
been rwognised. Furthermore in these genera there are clear a f i i t i e s
between some Eastern and Western Australian speciee. These affinities
have led to the construction of an hypothesis to amount for the observed
speciation pattern (see Evolution section).
BecauRe of these considerations the evidence for the species etaflu,
within the respective genera is reviewed in mme detail.
Analysis in the genera Heleiopotu9, Neobatrachw and Crinia waa
besed on: wason, time and temperature, and site of breeding; recording
and analysis of male calls (Littlejohn, 1957, 1958; Littlejohn and Main,
1959) mid later female discrimination trials (Straughan and Main, 1966);
and finally results of in vitro crosses were used as guides for making a
judgement aa to whether populations beinq compared shared a single
gene pool or not. If they shared the common gene pool they were
deemed to belong to one biological species; if they did not share the
gene pod then they belonged to two biological species. In some case8
these biological species were morphologioally distinguishable, in other
caws morphological distinctions were relatively minor (the so-called
sibling epecies). Whether a species waa morphologically distinguishable
or not was considered unimportant. What was important waa whether
there was one or more populati~ms, exploiting the different habitats
available in any locality.
A. Heleioporw,
The genuR Heleioporms is c o m p o d of moderate to large-sized burrowing frogs. Lee (1965,1967) recognises 6 species in the genus. One species,
H. aw6,diacu8, waa formerly regarded as having a disjunct distribution
in Eaetorn and Western Australia. However Lee (0;~. cit.) regards the
western population aa a morphologically distinct species (H. burycragw, Lae).
Each species tends to favour one soil type aa follows: H . barycmgw,
heavy clays and fast flowing streams which are dry during the summer;
H. inornatwr, sandy peat bogs; H . a l b ~ u W u a ,
sandy stream beds of
the winter rainfall area of the Western Australian plateau; H. eyrei,
ponds and marshes of the Perth coastal plain; H . psammophilus,
angular fine-grained humus-free sands.
The breeding biology of this genus is unique. The male excavates a
long burrow in early autumn a t sites which, at that time, are quite dry
but w5ich will fill with water aa soon aa winter rain falls. Having
excavated the burrow the male remains at the entrance and calls,
Females, when gravid, move to these sites and mate within the burrow
where the large unpigmented eggs are laid in a frothy mass. The egg
maas is sealed within the burrow by a small wad of earth after which
the burrow is abandoned. The eggs cleave and develop to tadpole stage
been rwognised. Furthermore in these genera there are clear a f i i t i e s
between some Eastern and Western Australian speciee. These affinities
have led to the construction of an hypothesis to amount for the observed
speciation pattern (see Evolution section).
BecauRe of these considerations the evidence for the species etaflu,
within the respective genera is reviewed in mme detail.
Analysis in the genera Heleiopotu9, Neobatrachw and Crinia waa
besed on: wason, time and temperature, and site of breeding; recording
and analysis of male calls (Littlejohn, 1957, 1958; Littlejohn and Main,
1959) mid later female discrimination trials (Straughan and Main, 1966);
and finally results of in vitro crosses were used as guides for making a
judgement aa to whether populations beinq compared shared a single
gene pool or not. If they shared the common gene pool they were
deemed to belong to one biological species; if they did not share the
gene pod then they belonged to two biological species. In some case8
these biological species were morphologioally distinguishable, in other
caws morphological distinctions were relatively minor (the so-called
sibling epecies). Whether a species waa morphologically distinguishable
or not was considered unimportant. What was important waa whether
there was one or more populati~ms, exploiting the different habitats
available in any locality.
A. Heleioporw,
The genuR Heleioporms is c o m p o d of moderate to large-sized burrowing frogs. Lee (1965,1967) recognises 6 species in the genus. One species,
H. aw6,diacu8, waa formerly regarded as having a disjunct distribution
in Eaetorn and Western Australia. However Lee (0;~. cit.) regards the
western population aa a morphologically distinct species (H. burycragw, Lae).
Each species tends to favour one soil type aa follows: H . barycmgw,
heavy clays and fast flowing streams which are dry during the summer;
H. inornatwr, sandy peat bogs; H . a l b ~ u W u a ,
sandy stream beds of
the winter rainfall area of the Western Australian plateau; H. eyrei,
ponds and marshes of the Perth coastal plain; H . psammophilus,
angular fine-grained humus-free sands.
The breeding biology of this genus is unique. The male excavates a
long burrow in early autumn a t sites which, at that time, are quite dry
but w5ich will fill with water aa soon aa winter rain falls. Having
excavated the burrow the male remains at the entrance and calls,
Females, when gravid, move to these sites and mate within the burrow
where the large unpigmented eggs are laid in a frothy mass. The egg
maas is sealed within the burrow by a small wad of earth after which
the burrow is abandoned. The eggs cleave and develop to tadpole stage