Entomologists amazed by new insect order from Namaqualand
Helen Theron
The recent recognition of a new order of insects, Mantophasmatodea, has
been dubbed as "one of the most exciting" recent discoveries in
Zoology, boosting the total number of insect orders (e.g. the beetles, flies,
fleas, etc) to 30.
The formal description by entomologists of the fairly large, wingless
creatures, which to the untrained eye resembles a cross between a grasshopper
and a praying mantis, is the first description of an insect order since the
discovery of ice crawlers (Grylloblattodea) in 1914, almost a century
ago.
Small and bandy-legged, the wingless insects from the new order are
aggressive carnivores, leaping on their prey and subduing them with their spiny
legs. They walk on their heels, and are grey, brown or bright green in colour.
The female is bigger than the male and often eats him after a prolonged and
uninterrupted copulation of about three days. The female lays a series of up to
10 egg pods in the sand, each containing about 12 eggs, which hatch and develop
during the wet winter months: adults appear in spring and die after about one
month. The new order has no common name as yet.
Though scientists have found the insects embedded in Baltic amber, suggesting
that they existed around 40 to 50 million years ago in Europe, the new order
appears to be restricted to southern Africa in present times.
 German insect anatomist Dr Klaus Klass and researchers Oliver Zompro, Prof
Niels Kristensen and Prof Joachim Adis, described the new order in Science
magazine (24 May, 2002, Volume 296, pp 1456-1459), based, on just two museum
specimens from Tanzania and Namibia.
Dr Eugene Marais (Windhoek Museum, Namibia) then alerted these entomologists
to a similar specimen in his collection, and in February this year led an
expedition to Namibia's Brandberg, discovering one of the specimens described in
the Science paper, plus another spiny species (dubbed the
"gladiator").
The article caught the attention of University of Cape Town entomologist Dr
Mike Picker. Though it referred to the Namibian and Tanzanian specimens, Picker
realised he and his students had frequently encountered the insects in South
Africa.
Picker wrote to Science reporting that he and students Jonathan Colville,
Anthony Roberts and Mark Kirkman had previously noted the unusual orthopteriod
insects in the semi-arid regions of the succulent Karoo (Namaqualand). "It
emerged that we hadn't realised the evolutionary significance of the creatures
we'd photographed in Namaqualand!" he added. He recovered 29 additional
pinned specimens in South African museums, collected from 1890 to 1994.
"Specimens from museum and field collections are currently known from about
30 localities, some of which are 600 km apart; and appear to represent at least
four species," Picker reported.
After Picker's letter appeared, Klass contacted him, and they subsequently
established a collaboration, the South African Mantophasmatodea Project, which
brings together researchers from Japan, Germany, Denmark, the US and Namibia.
(The Project also involves collaboration with the Iziko Museums of South Africa
and the ARC-Plant Protection Research Institute in Pretoria.)
The team will study, among other aspects of the biology of the group, the
relationship between the South African species and the Namibian species. Only a
single family, Mantophasmatidae, is currently recognised. Three species
have so far been identified in Namibia and at least four in South Africa.
Set against a universal scenario of shrinking biodiversity coupled with the
increasing extinction rates, the find of a new group of animals so fundamentally
different from all other insects groups both surprised and excited biologists,
who had assumed that most major animal discoveries had already been made. The
apparent centre of distribution of the group in the Succulent Karoo of South
Africa adds yet another biological jewel to the already impressive concentration
of endemic plants and insects of this region.
In UCT's Zoology Department, the numerous cultures that daily consume vast
quantities of drozzies (small vinegar flies) will hopefully provide answers to
some fundamental questions, such as the evolutionary relationship of the Mantophasmatodea
to the existing insect orders.
Photos by Dr Mike Picker.
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