AW Insect Book: Sawflies, Wasps, Bees & Ants (Hymenoptera)

[Klipspringer]

Ponerine Trap-jaw Ant Odontomachus troglodytes
Subfamily: Vespoidea. Family: Formicidae. Subfamily: Ponerinae

© Richprins
Marloth Park

Ants of the ponerine genus Odontomachus are large and slender and have a bizarre head with strong jaw-muscles and large, elongate trap-jaws which are carried sideways when foraging, ready to snap shut as potential prey comes in touch with the long frontal trigger hairs.
They have a powerful stinger at the apex of the abdomen.
Mandibles are straight and narrow, articulating with the head medially, capable of being held open at 180°, and with a trio of large apical teeth. There is a pair of long trigger setae below the mandibles.The head is strangely shaped: much longer than wide, with a distinct constriction behind the eyes and the posterior margin of the head almost straight. The eyes are fairly large and located anterior of head midline on temporal prominences. Propodeum broadly rounded dorsally, as broad as mesonotum but narrower than pronotum. Petiole topped by a posteriorly-directed spine, notably bent posteriorly at base. Gaster without a girdling constriction between pre- and postsclerites of A4. Head and body shiny to lightly striate, with very sparse pilosity and pubescence.

Like other ponerines, they display a suite of characteristics that are often considered ancestral in ants, including small colony size, monomorphic workers, little differentiation between the workers and queen, and solitary foraging.

Odontomachus troglodytes is widespread across sub-Saharan Africa in forests and open habitats.

The trap-jaw mechanism allows them to instantaneously close their long, sturdy mandibles to catch prey or to defend themselves. Photoelectric scanning has revealed that these trap-jaws can be closed in less than 0.5 ms and that they decelerate before they collide with each other. The mandible strike is released in a reflex-like action when particular trigger hairs are touched. This reflex takes 4 to 10 ms and is probably the fastest reflex yet described for any animal. This speed is based on a catch mechanism in the mandible joint that keeps the extended mandibles open during contraction of the powerful closer muscle and allows the potential energy it produces to be stored within cuticular elements, apodemes, and the closer muscle itself. During a strike a relatively small specialized trigger muscle unlocks the catch, instantaneously releasing the stored energy to accelerate the mandible.

Like in most other insects, two muscles are primarily responsible for “normal” mandible movement in ants: the mandible opener (abductor) and the mandible closer (adductor) muscles. The mandible moves as a simple hinge, with the closer and opener muscle attaching, respectively, to the medial and lateral portion the mandible base.
Trap-jaw ants have modified the basic ant mandible plan by inserting specialized latch, spring and trigger structures that together enable a catapult mechanism. This mechanism allows muscles to build up power over the course of seconds and then release it in less than a millisecond. A latch keeps the mandibles open even when the mandible closer muscle contracts, allowing potential energy to slowly be stored in a spring until a specialized “trigger muscle” releases the latch and the mandibles shut nearly instantaneously.

The unique morphology and record-breaking speed of trap-jaw ant mandibles clearly mark these ants as specialized predators, and numerous studies have confirmed that trapjaws are fast enough to capture insects with rapid predator escape mechanisms or chemical defenses.
Foragers search for prey usually with their mandibles in an open position, presumably in anticipation of striking prey. After detecting prey with their antennae, foragers approach with speed, and use their trigger hairs to position their prey in striking range of the apical teeth of their mandibles. After striking, often multiple times, foragers may also sting struggling prey before carrying it back to the nest.
However, trap-jaw mandibles can also be used in defense or escape during interactions with competitors or predators for individual escape by striking the substrate and launching themselves away from potential predators. When disturbed, these ants use trap jaw propulsion to ‘‘jump’’ away.


Links:
https://www.antwiki.org/wiki/Odontomachus_troglodytes
https://youtu.be/MdExxcRrC9g

[Klipspringer]

Ponerine Ant Platythyrea schultzei
Subfamily Vespoidea. Family Formicidae. Subfamily Ponerinae. Tribe Platythyreini

© ExFmem
Kruger National Park

The ponerine genus Platythyrea is distributed in the tropics and contains 38 extant species, seven species are recorded from South Africa:
Platythyrea arnoldi, P. cooperi, P. cribrinodis, P. lamellosa, P. matopoensis, P. modesta and P. schultzei.
Their colonies’ reproductive structures vary greatly among species. Colonies of the African species, Platythyrea cribrinodis, P. schultzei, and P. lamellosa reproduce by mated workers without morphologically distinctive queens while the African P. arnoldi and Malaysian P. quadridenta show sexual reproduction by both workers and dealated queens. Platythyrea conradti is the only species in this genus with ergatoid (= permanently wingless) queens. Colonies lack gamergates (unlike other species in this genus), yet aggressive interactions among queen and workers define a hierarchy. A single fertile queen has the top rank and highranking workers do not lay eggs, except when the queen dies. Furthermore, the American species, P. punctata, shows thelytoky in which virgin workers lay diploid eggs that will become workers.
Thus, comparative studies of reproductive structure and ecology in Platythyrea are important for understanding the diversity of reproductive biology in ants.
Unusually among ponerines, many Platythyrea species are arboreal, nesting in hollow branches or other preformed cavities in live or fallen trees, and foraging on tree trunks or other vegetation. Some large African species (e.g. Platythyrea lamellosa) are terrestrial and nest at the base of termitaria or under rocks.
Platythyrea workers are very fast runners, and their speed combined with their potent venomous stings enable them to rapidly catch and subdue a wide range of prey. Some Platythyrea species are generalist predators (e.g. P. conradti and P. modesta), but many reportedly specialize on termites and at least one species (Platythyrea arnoldi) is apparently a specialist on adult beetles.
Platythyrea workers typically forage individually. Interestingly, workers of P. modesta sometimes carry larvae directly to their prey, rather than bringing the prey back to their nest; this behavior is otherwise unknown within the Ponerinae.
Diagnostic characters of Platythyrea workers and queens include (in combination) pruinose sculpturing, broad insertion of the clypeus between the frontal lobes and the consequently widely spaced frontal lobes and antennal insertions, laterally opening metapleural gland orifice, metatibiae with two pectinate spurs, toothed tarsal claws, and projection of the helcium from near midheight on the anterior face of A3. Antennal segment count 12. Sting present. Gaster with a moderate girdling constriction between pre- and postsclerites of A4. Eyes large to moderate in size, located anterior to head midline.

Description
Platythyrea schultzei is a medium-sized (8.5-9.5 mm), black ant with reddish legs and antennae.
Head width (eyes omitted) >1.0 mm; in full-face view, scapes overreach posterior margin of head slightly.
Second segment of antennal funiculus about the same length as third, and much shorter than eye.
Posterodorsal extremity of petiolar node between lateral teeth rounding downward into posterior face, without a sharp projecting margin
Mandible near base with a strong dorsolateral groove.
Sculpture opaque, with many conspicuous large punctures on petiole and other dorsal surfaces.

Distribution
Afrotropical Region: Angola, Democratic Republic of Congo, Kenya, Mozambique, Namibia, South Africa, Uganda, Zambia, Zimbabwe.

Biology
Colonies are small, containing 10-40 members, and are found up trees in dead, dry branches and in shallow, unstructured nests under stones, often occupying deserted termite galleries.
Workers forage alone. Recorded prey items are ants, termites, small beetles and bugs of several families, grasshopper nymphs.
Colonies of Platythyrea schultzei are obligately queenless, containing only morphologically and anatomically similar, monomorphic workers. The role of the queen is filled by a single inseminated worker in each colony. The ovaries of this worker are physiologically active, while oogenesis is repressed in its nestmates.
Colony labour is organised into five groups of tasks: care of eggs, care of larvae, care of cocoons, and general colony maintenance, including foraging. The mated worker monopolize the task of caring for the eggs. Organisation of the remaining ants to carry out the other tasks shows a clear pattern of age polyethism, through which all workers except the mated worker pass. There is no indication that division of labour is based on or biased by size differences amongst the workers.
The behavioural marker (carrying eggs) for the mated worker allows its experimental removal from each colony. In each case its role is taken over by a single, young, uninseminated worker that undergoes ovarial development and assumes the same behavioural characteristics and control over its nestmates' oogenesis as the previous mated worker. Thus insemination does not appear to be a prerequisite for the physiological differentiation of an individual to fill the role of reproductive.




Links:
https://www.antwiki.org/wiki/Platythyrea_schultzei
https://www.antwiki.org/wiki/Key_to_Afr ... ea_workers
https://www.tandfonline.com/doi/pdf/10. ... 1.10539472

[ExFmem]

Pollen Wasp Quartinia sp.
Family Vespidae Subfamily Masarinae Tribe Masarini




Kgalagadi TP by ExFmem

Subfamily Masarinae

Distribution
Masarinae (pollen wasps) are found principally in Mediterranean and temperate to hot, semi-arid to arid areas outside the tropics. The masarine wasps number around 350 known species, 78% occur in the Afrotropical and Palaearctic Regions combined, with 47% in the Afrotropical Region and 31% in the Palaearctic. The remaining 22% of the species are 10% Australian, 7% Neotropical and 5% Nearctic. Of the 151 species recorded from the Afrotropical Region, 144 are restricted to southern Africa. Most of these species are found in the west, where many are narrowly endemic.

Biology
Masarines differ from all other aculeate wasps in the nature of their provision, which, like that of the bees, is typically composed of pollen and nectar. Unlike most of the bees, none of the masarines is equipped with pollen carrying devices on the legs or abdomen. The pollen and nectar mixture is carried in the crop.
They are important flower visitors and pollinators. Aizoaceae (Mesembryanthema) and Asteraceae, both of which are similarly species diverse, are visited respectively by 45% and 49% of the pollen wasp species. In addition, and of particular interest, are the close associations of some species with other plants of which they are in many instances the sole or most dependable pollinators.
In all species oviposition precedes provisioning, the egg being laid at the inner end of the cell, lying loose or attached.

Genus Quartinia (Ed. André 1884)




There are 87 described species of Quartinia with more species described and awaiting publication.

Description
Quartinia species range in length from a little over 2 mm to 7 mm. In comparison with the great majority of species of other genera of Masarinae even the largest Quartinia are relatively small.
Like Celonites but unlike all the other Masarinae, their wings fold longitudinally and the antennal club is rounded.

Distribution
Quartinia is found throughout the distribution range of Masarinae in southern Africa.

Throughout the more arid areas, including the true desert, the Namib and southern extensions thereof, Quartinia is species diverse, can be considered one of the most common insects, and is often present on flowers in large numbers. This is in contrast with the other pollen wasp genera, which are either absent (Priscomasaris and Ceramius) or poorly represented (Jugurtia, Masarina and Celonites) in the most arid areas.

Biology
Aizoaceae and Asteraceae are of great importance as forage plants. Of the 51 species for which flower visiting records are available, 71% have been recorded from Aizoaceae and 53% from Asteraceae.



Nesting - Quartinia species excavate a burrow in friable soil. This they surmount with a turret and within each excavated cell construct another cell. They are unique amongst the Masarinae worldwide in that they have retained the larval ability to spin silk, which they use as a bonding agent in the stabilisation of the burrow and construction of the turret and cells. The silk used in nest construction is spun by the nest-builder. One individual was observed whilst constructing its nest. It was joining together sand grains with silk and whilst so doing was rotating its head, the silk was apparently issuing from its mouth.

https://www.sanbi.org/sites/default/fil ... ies-24.pdf

[ExFmem]

Sycamore Fig Wasp Ceratosolen arabicus (Mayr 1906)
Family: Agaonidae.


The fig wasp family, Agaonidae, belongs to a superfamily of wasps called Chalcidoidea that includes thousands of species of parasitic wasps.


Kruger NP, May by ExFmem (female)


Ceratosolen arabicus is the pollinator of the Sycamore fig, Ficus sycomorus sycomorus. It may be one of nature’s oddest couples: a tiny wasp that can barely be seen, and a giant fig tree, the sycamore, which shelters a remarkable menagerie of wildlife among its limbs. The wasp and the fig depend on each other for survival. Without the wasp, the tree could not pollinate its flowers and produce seeds. Without the fig, the wasp would have nowhere to lay its eggs.


Diagnosis (female):
*Gaster: Laterally compressed; distinct tail formed only by the ovipositor and its sheaths ; valves of the ovipositor extruding. Ovipositor sheath as long as the gaster.
*Fore wing not extremely densely pilose and marginal vein slender
*Head: dorso-ventrally flattened; usually with 3 ocelli.
*Face medially has a groove into which the antennal scapes fit, when folded back
*Antennae: Scape strongly broadened; the 3rd antennal segment apically produced into an appendage (which can be used as a crowbar in removing/lifting ostiolar bracts)
*Mouth parts: the mandibles are situated underneath the head, possess a posterior flat appendage provided with ventral lamellae or rows of teeth (which help to anchor the body in front and pull forward when entering the fig ostiole
*Thorax: Usually smooth and flat. Fore and hind legs short and strong; tibia with stout teeth (to push the body forward through the ostiole while entering the fig)
*Fore leg tibia with a dorso-apical comb of 4 teeth.

Distribution
Senegal, Guinea, Ivory Coast, Nigeria, Cameroon, Chad, Yemen, Ethiopia, Kenya, Uganda, Tanzania, Democratic Republic of Congo, Malawi, Zambia, Zimbabwe, Namibia, Botswana, South Africa, Madagascar, but likely to be present throughout the rest of the host fig distribution areas.

Biology
How then do these tiny wasps that only live for a few days manage to perform their amazing task of finding and pollinating flowers that are hidden inside the fig?



Female fig wasps leaving the fig they have bred in need to fly off in search of another fig tree to continue the reproductive cycle, often a long and arduous journey, which only a few individuals out of thousands manage successfully. This remarkable feat is achieved by homing in on host tree-specific volatiles, a chemical signal released by the fig when it is receptive for pollination. Completion of this journey is the first test of endurance, as once the pollinator has located a receptive fig, she needs to circumvent the next barrier. The only link the fig cavity has to the outside world is through a tiny bract-lined opening at the apex of the fig, called the ostiole, and it is by means of this passage that the pollinating fig wasp gains access to the florets. Negotiating the ostiole is no easy task, with the female wasp having to squeeze and labour her way between the tightly closed bracts. She is, however, remarkably adapted to do so. Her body, in particular her head and thorax, is extremely flattened and elongate. She also has rows upon rows of backward pointing teeth on her mandibular appendage, situated on the underside of her head, as well as a few strong teeth on her legs. These teeth assist her progress through the ostiole and also prevent her slipping backwards. Nevertheless, the process of gaining access to the fig cavity is so difficult that her wings and antennae usually break off in the ostiole, but this fortunately does not influence her pollinating or egg-laying ability.

The female wasp then proceeds to pollinate the stigmas and to lay eggs in the ovules of some of the florets. This she does by inserting her long ovipositor down the inside of the style. The florets that have styles longer than the wasp’s ovipositor are pollinated, but no eggs are laid in the ovule and hence these florets set seed. The wasp larvae feed on the endosperm tissue in the galled ovary and larval development correlates strongly with host fig development, encompassing anything from three to twenty weeks. Once the wasps have reached maturity they chew their way out from the galls and emerge into the fig cavity within a short period of each other. The wingless males mate with the females before chewing a hole through the fig wall to the exterior to allow the females to escape – the male’s only two functions in life, as he dies soon afterwards! The females either actively load up pollen from ripe anthers into special pollen pockets, or in some species passively become covered with pollen, before exiting the fig in search of young receptive figs to complete the cycle.


http://www.figweb.org/Interaction/How_d ... /index.htm

[Klipspringer]

Pollination of a Sycamore Fig by the Fig Wasp Ceratosolen arabicus

The wasps’ entry into the syconia is a fixed sequence of behavioral events. A female wasp arrives at and immediately begins antennating a syconium. The wasp assumes a characteristic pose during this "assessment behavior." The antennae are arched up and the distal portion of the antennae contact the syconium surface perpendicularly, with only the distal antennal segment actually touching the syconium. After assessment the wasp may walk off the syconium and search for other syconia on the same branch, fly away, or begin the next phase of entry.
If the wasp attempts entry, she lowers her antennae, and the distal five or six antennal segments are pressed flat against the syconium surface. The wasp is searching for the ostiole. When she finds the ostiole she loosens the topmost scale with one of the sharp, sclerotized horns on the third antennal segment. If the upper scale is stuck to the tissue layer below, as is often the case on syconia that have not yet been entered, she approaches at an angle, hooks one horn under the scale, and works the scale free by pushing up with her forelegs and head. When the scale is loosened, she is ready to begin entry. The legs are spread laterally from the body, and the ventral surface of the entire body is flattened against the syconium surface. The antennae are forward and also pressed against the syconium; the wings are raised perpendicularly to the thorax and pressed together; and the abdomen is compressed dorsoventrally. The wasp now pushes her antennae and head under the topmost scale of the ostiole. She slowly disappears, and as her thorax passes through the topmost scale her upraised wings detach. When several wasps enter a single syconium, a tuft of wings can be seen at the entrance to the ostiole. As the female passes under the top scale, she contacts and pushes her head under the lip of the second scale, and continues walking the helical ostiole. The antennae distal to the fourth or fifth segment detach during entry. Wasps are not always successful at passing through the ostiole, and are sometimes found dead within the scales of the ostiole.

After wasps arrive in the central cavity of the syconium they oviposit and pollinate during the day or two before they die.
The Female wasp enters the fig with her pollen sacks laden with unintentionally collected pollen and pollinates those female fig flowers with longish styles. These long styles prevent the wasp from reaching its Ovary and thus from laying eggs in it. The wasp targets the flowers with short styles and lays a single egg in each one.

Within these fig inflorescences there is polymorphism in style length among the pistillate florets. The fig wasp’s ovipositor is long enough to reach down shorter-styled florets and into the ovary, but is usually not long enough to reach down longer styles and into the ovary.
Thus the short-styled florets usually produce wasps, while the longstyled florets usually produce seeds.

Eggs are laid by extending the ovipositor down the style and into the ovary of a pistillate floret, where the larva will develop while feeding on the
tissues associated with the developing seed. These female flowers react to the egg, producing a gall, which nourishes the developing larvae. They eventually pupate and becomes adult wasps.

After females lay eggs, the wasps die in the central cavity of the syconium. The larvae and seeds develop.
The male progeny emerge from the ovaries of the pistillate florets in which they developed. The robust Male wasps develop first, fertilize the young Female wasps and then burrow through the wall of the fig, allowing oxygen in.

The males have reduced eyes and little pigmentation. Their legs are short and thick, and their abdomens curl under the ventral surface of the thorax and head. The males wander through the labyrinth-garden of swollen pistillate and now mature staminate florets, searching for females. These females are mature, but remain quiescent in the floral ovaries in which they developed. When a male finds an ovary containing a female, he chews a hole, inserts his telescoping abdomen, and mates with the female.

After a one to two day mating period, one or more males chew(s) an exit tunnel through the wall of the syconium. Following completion of the exit tunnel, the females widen the hole in the floret ovary created by the male during mating, and then struggle free into the central cavity of the syconium. Their wings are stuck to the abdomen and the pupal skin still covers their heads. They quickly groom their wings free by passing their rear legs between the wings and upper abdomen while simultaneously removing their pupal skin from their head with their forelegs.
After grooming, the female wasps now load pollen from the male fig flowers. After several loads have been collected, the wasps leave the syconium through the exit tunnel and quickly take to the air. Those wasps that successfully find receptive syconia begin the cycle again.
This is an excellent example of a mutualistic relationship between the fig tree and the wasp, where both benefit.

[Klipspringer]

Spider-hunting Wasp Homonotus ruficornis
Superfamily: Vespoidea. Family: Pompilidae. Subfamily: Pompilinae


© Richprins
Marloth Park, July 2020

Identification
Size: 6.5-10 mm. The species is identified by a red apex of the abdomen. Clypeus and antennae are red.
Female: Colour: Black with the following parts light red: clypeus, mandible, antenna including scape, tarsi, abdominal segments III-VI. Clypeus, parts of legs and declivity of propodeum with long white pubescence. Tibial spurs white, wings slightly infuscate.
Male: Colour: Black, red are: Apical clypeal margin, antenna (apically darker), tergites and sternites III-VII, tarsal segments partly. Wings infuscate, apical spurs of mid- and hindtibia whitish.

Distribution
Egypt, Israel, Central and Southern Africa

Females hunt spiders to provision their nest with. The paralysed spiders are carried or dragged to a pre-constructed nest, where they lay an egg on the spider. On hatching the larva feeds on the preserved prey item. Adult wasps feed on nectar for their energy requirements.


Links:
http://www.waspweb.org/Vespoidea/Pompil ... /index.htm
https://www.zobodat.at/pdf/LBB_0050_1_0809-0824.pdf

[Klipspringer]

Spider-hunting Digger Wasp Trypoxylon sp.
Superfamily Apoidea. Family Crabronidae. Subfamily Crabroninae. Tribe Trypoxylini

t1.jpg (112.21 KiB) Viewed 1074 times

Nelspruit © Richprins

Trypoxylon is a cosmopolitan genus, of the 631 species of Trypoxylon recognised occur around 75 occur in the Afrotropical Region, the largest number for any region in the Old World.
Trypoxyline wasps are solitary and predatory, provisioning nest with paralyzed spiders (Aranaea) that is either constructed in the ground, or constructed from mud within sheltered situations, or in pre-existing cavities such as hollow stems, or old abandoned nests, or key-holes. Trypoxylon is a familiar wasp around human habitations and due to the frequent use of keyholes for nesting by some species they are commonly known as ‘keyhole wasps’.

Links:
https://www.waspweb.org/Apoidea/Crabron ... /index.htm

[Klipspringer]

Paper Wasp Polistes cf. badius
Family: Vespidae. Subfamily: Polistinae

Polistes badius.jpg (93.16 KiB) Viewed 1070 times

Nelspruit © Richprins

Biology
Social, constructing communal paper nests comprising a single horizontally orientated comb with downward pointing cells. Larvae are fed on chewed-up, soft-bodied insects such as caterpillars.

Links:
https://www.waspweb.org/Vespoidea/Vespi ... badius.htm
https://www.galerie-insecte.org/galerie ... adius.html

[Klipspringer]

Paper Wasp Ropalidia distigma
Family: Vespidae. Subfamily: Polistinae. Tribe: Ropalidiini

Ropalidia distigma.jpg (58.74 KiB) Viewed 1058 times

On an euphorbia in Marloth in July 2020 © Richprins

Some history
This species was first collected by Wilhelm Peters. Wilhelm Peters (1815-1883) was the assistant of Johannes Müller, the great anatomist and was later appointed Professor of Zoology and director of the Zoological Museums at the Royal University of Berlin.
Early in his career, Peters began to plan what was to become the major event of his life, an exploration of Mozambique, which had the enthusiastic support of Müller and of Alexander von Humboldt, then also at Berlin. The expedition was funded by king Friedrich Wilhem IV. Peters departed in September 1842, travelling on a Portuguese convict ship first to Angola and finally (June 1843) to Mozambique. There he managed to explore the entire coastal region and also spent nearly a year up the Zambesi River deep in the interior. The collections he made were enormous and were written up during the next decades, mainly by himself. Some taxons however were examined and decribed by his co-workers. The chapter on Hymenoptera in Peter's 5th volume of his "Naturwissenschaftliche Reise nach Mossambique, auf Befehl Seiner Majestät des Königs Friedrich Wilhelm IV, in den Jahren 1842 bis 1848 ausgeführt, von Wilhelm C. H. Peters" (1862) was provided by the zoologist and entomologist Carl Eduard Adolph Gerstaecker who became in 1857 the curator at the Zoological Museum of Humboldt University.

To this day, there is no other scientific description available for this species, so here Gerstaecker's original description:

Gerstaecker Ropalidia distigma.jpg (83.2 KiB) Viewed 1058 times

https://www.biodiversitylibrary.org/ite ... 1/mode/1up

Diagnostic for the species is the narrow yellow apical band on second tergite. The second abdominal segment is enlarged and has a bell-shape appearance. The other segments can telescope into this and are retracted causing the characteristic shrunken appearance.
The hyaline forewings have a dark spot on the edge.
Body covered with dense appressed tomentum.

Biology
Social, constructing communal, vertically orientated paper nests with horizontally orientated cells. Larvae are fed on chewed-up, soft-bodied insects such as caterpillars.

Distribution
Kenya, Mozambique, South Africa, Tanzania, Zimbabwe.

Some museum specimens:

http://www.zsm.mwn.de/drawers/HYM/Vespi ... 1604_1610/

Links
https://www.waspweb.org/Vespoidea/Vespi ... stigma.htm

[Klipspringer]

Velvet Ant Tricholabiodes sp.
Superfamily Vespoidea. Family Mutillidae. Subfamily Dasylabrinae. Tribe Dasylabrini.

Kgalagadi Transfontier Park Nov 2017.jpg (168.42 KiB) Viewed 1050 times

Male, Kalahari Tented camp, Kgalagadi Transfrontier Park © nan


Mutillids, commonly called velvet ants, are well represented in southern Africa, several hundred species in about 30 genera are known. Females are most usually red and black with bands or spots of silvery white and are invariably wingless, whereas the males which may be similarly coloured or may be predominantly black, are with few exceptions winged, the wings of most species being dark.
Night flying mutillids, such as species of Tricholabiodes, are pale ginger in colour.

Mutillids are ‘parasites’. They develop in the cocoons or puparia of other insects, most commonly wasps and bees, but also flies, beetles and moths. The egg is introduced into the cocoon or puparium where the mutillid larva feeds on the mature larva or pupa of the host. As the host is at
that time in a non-active stage, it is not stung, the sting of mutillids being solely for self-defence. Mutillidae do not appear to demonstrate any great degree of host specificity - rather, they appear to be associated with a particular ecological niche and to attack suitable host species found
within that niche. Any species of mutillid is therefore not necessarily limited to a single species or genus of host.

There are several species recorded from the Kgalagadi Transfrontier Park: T. concavus, T. imbellis, T. lividus, T. testaceus

Tricholabiodes, like other mutillid wasps, shows pronounced sexual dimorphism with the males being winged while the females are wingless. The differences in morphology and coloration between the male and female are such that it is only possible to associate the two sexes of the same species if one is able to catch them in copulo. Thus, for a majority of the species only one sex has been identified. Most probably, the two sexes of the same species are described under different names.

Description Genus Tricholabiodes
Males: Mesosoma golden yellow to medium reddish-brown. Head wider than long. The entire body, particularly head and metasoma, covered in long, pallid setae. Forewings partially darkly infuscated posterior to marginal cell.

Distribution
Tricholabiodes, one of several genera of nocturnal mutillids, is restricted to the arid and semi-arid regions of Africa and the Palaearctic. Its distribution in southern Africa includes all four arid biomes: Nama Karoo, Succulent Karoo, Desert and arid parts of the savanna, covering the western coastal belt between 12°S and 33°S and extending into the Kalahari basin and central Karoo plateau as far as 33°E.

Biology
Ectoparasitoids of larvae or pupa of other insects. There is only one host record (Gess & Gess 1997); it is a single undescribed female reared from the cell of a Ouartinia sp.
Nocturnal.

Links:
https://www.waspweb.org/Vespoidea/Mutil ... pecies.htm
https://researchspace.ukzn.ac.za/xmlui/ ... 0413/10309