Herpetofauna of the eastern African forests - Biogeography and Ecology of the Rain Forests of Eastern Africa - page 187

recently been discovered in forest near Chita
(Clarke, 1988a). The reefrog Phyliaimantis
keithae is known only from three localiies in the
Uzungwa Mountains. Cnemaspis uzungwae, a
gecko, has recently been described (Perret, 1986).
The chameleon Chamaeleo laterispinis, which
closely resembles the lichen Pannelia, is unique in
the structure and posiion of spines on the side of
its body and in its pattern of coloraion. A newly
described skink in the genus Leptosiaphos is known
only from leaf litter of the Mwanihana Forest
Reserve in the Uzungwas (Broadley, 1989).

Pattens of speciaion in the
amphibians and reples of the easten
forests of Africa

Sp eies ound in both the easten and Guineo-
Congolian oress of Africa

Three species of repiles have recognised subspe-
cies as listed in Table 9 . 2 . In the case of the lizard
Ho laspis guentheri, the easten populaions seem to
follow a roughly Easten Arc distribution pattern
south to central Mozambique with the westen
populations centred in the western forest block.
For the viper Bitis gabonica, a much more wide-
spread species, the subspecies found in eastern
Africa also extends west to Nigeria and to the
south, through to southen Africa, and the second
subspecies occurs far to the west, from Ghana
west to Guinea. Although in Tanzania B. gabonica
appears to be very much a orest-dependent spe-
cies, in southern Africa under certain condiions it
appears to be sympatric or nearly so with B..
arietans, a species of much more open country,
and in Tanzania, one which is not known to occur
in forest. Broadley & Parker (1976) reported a
case of B. gabonica x B. arietans hybridisaion fol-
lowing destrucion of forest, and Hughes (1983)
considers B. gabonica to be a forest form which
occurs only rarely in savanna.
The situaion with regard to Atheris nitschei is
somewhat different. Members of both subspecies
occur within Tanzania; those in the western for-
ests are members of one subspecies which
extends west into easten Zaire, while those south
of Kigoma and in southwesten Tanzania, north-
en Malawi and northeasten Zambia belong to a
second.

Taita Hils enemis

Only one forest form is known to be endemic to
the forests of the Taita Hills, the caecilian Af ro -
caeciia taitana. Unil recently the evidence sug-
gested that the Taita area was or had been
completely isolated from the Tanzanian Easten
Arc fauna, but the discovery of the microhylid
frog Ca/luina krfii indicates an affiniy with the
larger, more southen forests (Beentje, Ndiangui
& Mutangah, 1987; Beentje, 1988).

Coasal endemis

Two species of hyperoliid treefrogs, Hyperolius
ubrovenniculatus and Afixa/us sy/vaticus, are
endemic to Kenyan coastal forest. A new species
of Stphpaedes toad has been found on Mafia
Island in remnant forest (K.M.H., unpublished
data). Melanosps ronoensis is a limbless skink
known only from the Rondo Plateau. Recent
studies by Clarke (l988b) indicate that the dwarf
toad Bufo lindneri, formerly regarded as endemic
to the Dar es Salaam area and coastal forest in the
Pugu Hills, is in fact much more widespread and
not endemic to coastal forest. A diurnal gecko,
Lygoay/us howelli, has been ound only in
groundwater forest on Zanzibar (Pasteur &
Broadley, 1988), and on Mafia Island (K.M.H.,
unpublished data), and the lacerid lizard
Gastrpho/is vittata is known only from coastal for-
est in Tanzania and Mozambique.

Pattens of speiation in speies limited largey
to the Ta nganyika-Nyasa oress

A number of populations of amphibians and
repiles isolated on the various mountain block
forests have been designated as subspecies, but
not all of these are recognised today (see Table
9.3). Subspecific status has been assigned to
ewer species of amphibians than repiles. For the