Hymenochirus is a genus in the Family Pipidae
and contains two species and perhaps one subspecies. Members
of the Pipidae family have certain characteristics in common,
one of them being that they are tongueless. Another characteristic
is their tapered heads and circular lidless eyes. The two species
look very similar to each other. For example, this photo
is of H. boettgeri and this photo
is probably of H. curtipes. The major distinction between
the species is that H. curtipes reportedly has a distinctively
wartier skin than H. boettgeri. The best way to tell these
two species apart however is during the tadpole
stage. It seems that H. boettgeri is the most common
species in the pet trade.
Males and Females
In H. boettgeri the males are slim and when mature
they will develop a small gland behind each of their front legs.
This gland is called a post-axillary subdermal gland. It
looks like a small pimple. These glands apparently play some
part in mating, but their role is not well understood.
Listen to the Male's Mating
The females of the species tend to be a bit larger (about 20%)
than the males. They will become
almost pear-shaped when mature and their abdomen fills with eggs.
The females typically have a slightly longer tail than the males.
The males of the genus are the only ones who "sing"
or "hum." Like most frogs, the singing is designed
to attract a mate. The males will sing even if no females are
in the tank. If your dwarf frog sings, it's a male. In H.
boettgeri, sexual maturity begins at about nine months of
African dwarf frogs mate during what is called amplexus. In
amplexus, the male grasps the female around the abdomen just
in front of her hind legs. Amplexus usually occurs at night after
one or more nights of singing by the male. During amplexus, the
female does all the swimming. The female lays her eggs on the
surface of the water, one at a time while towing the male. She
will swim to the bottom of the between layings. The male is fertilising
the eggs during this time by releasing sperm into the water.
Amplexus can last for several hours. When the female has laid
all her eggs she signals the male to release her by going motionless.
The first time I saw this behavior I though that the female had
died. After several minutes of motionlessness the male will release
the female and she will return to her normal behavior.
A common misconception is that these aquatic
amphibians can be cared for as if they are goldfish. Though they
can thrive in a tropical fish aquarium special care must be taken
to prevent them from starving to death. These frogs are bottom
feeders. Their preferred diet consists of blood worms (live or
frozen), small (or chopped) earthworms, tubifex worms, etc. I
have observed them eating fish flakes only on rare occasions
and never in any quantity. I have heard from numerous owners
reporting that freeze-dried food has caused health problems in
their frogs. I suspect that the freeze-dried food causes intestinal
blockages that are usually fatal.
African dwarf frogs seem to be visual hunters, but it's likely
that they can also detect food by scent. Their nearly binocular
eyesight will detect movement once they are close to the food.
They feed by striking suddenly at their prey. They don't chew
their food, but gulp it down whole. These frogs will eat huge
amounts of food for their size. Care must be taken not to over
feed as they will search for any and all food in their tank and
eat until every morsel is gone. It's best to feed them every
other day. Adjust the amount of food so that their bellies are
just beginning to bulge when the food is gone.
H. boettgeri and H. curtipes are unusual for frogs
in that they do not ever need to leave the water. In fact they
will dehydrate very quickly if they do. Their water should be
filtered and temperature controlled. Frogs are not able to regulate
their body temperature internally the way other animals do. Frogs
rely on their environment being the proper temperature for them
to be comfortable. H. boettgeri will do well
at a temperature of 25 degrees C. (77 degrees F.). They do not
appear to be bothered by a few degrees of fluctuation overnight.
H. boettgeri and H. curtipes come from the Congo
region of Africa and are adapted to a higher pH than most aquariums.
H. boettgeri will do best in a tank with a pH of 7.6 to
7.8. Since most fish prefer a pH closer to 7.0 you might want
to consider putting H. boettgeri in their own tank, especially
if you want to do any breeding.
I was able to keep a Chinese algae-eater and a corry catfish
with my frogs at the higher pH with no problems. I recommend
these types of fish for your frog tank as they help keep the
tank clean and they don't harass the frogs. Gold fish and most
tropical fish can be very aggressive to the dwarf frogs and they
will compete with the frogs for their food.
I have written a detailed account of
my recent breeding events which includes my tank setup and water
I believe that live food should be supplied whenever possible.
Here are some resources:
Blue Spruce Biological
These folks can supply you with everything you need to raise
You'll be dealing with Jerry Tresser. He's quite a character.
He's also honest and very knowledgeable about Drosophila melanogaster
and Hydei sturdivant. His prices are very competitive
These folks sell Artemia which is a brine shrimp native to The
Great Salt Lake in Utah. Live brine shrimp
are an excellent food source for fish and H. boettgeri.
If you decide you want to raise tadpoles there
are several essentials.
It is extremely important to understand how
to establish and maintain a high level of water quality within
your aquarium. This is especially true if you are keeping fish,
but is also true if you are keeping aquatic frogs. Poor water
quality will shorten the life of any species by exposing it to
toxins and will make an aquatic animal more prone to disease
and infection. I have assembled some information that discusses
what water quality is and how best to maintain it.
The Biological Cycle is an excellent introduction from the
folks at Aqua Biotechnology.
For deeper reading I highly recommend this paper:
Biological Filtration and Aquarium
Health Maintenance. It's well
illustrated and very readable.
On the Lighter Side...
is the site that got me started on my breeding project. This
award winning site has been going since 1995 and is hopping with fantastic
frog facts and fun!