Esphex wasps . Genus of hymenoptera of the family of the Sphecidae , tribe of the sphegines.
Summary
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- 1 Biological characteristics
- 1 Playback
- 1.1 Nesting
- 2 Species of Sphex
- 1 Sphex Maxillosa
- 2 Spex Occitanica
- 3 Sphex Funerarius
- 4 Sphex pensylvanicos
- 5 Species in Cuba
- 3 Source
- 1 Playback
biological characteristics of Esphex wasps
Filamentous antennae, the jaws large, curved, with two teeth on their inner face, the propectum narrow, strangulated, the prenotum swollen and also strangulated, the abdomen with a single-segmented peduncle , cylindrical, smooth, the tibias with a spiny outer edge , the nails with teeth on the lower surface, and the forewings with three transverse ulnar veins, the second ulnar cell receiving the first recurrent vein, and the third the second.
Reproduction
Sphex in the mating process
Build a cave with the entrance on top of a mound. He lays the eggs inside it and goes hunting, a cricket , a grasshopper or a caterpillar , sticks its stinger into it to inject toxins that paralyze it but keep it alive.
It drags its prey to its nest , introduces the prey into the cave, depositing it next to the eggs , it will remain alive until they hatch and eat it. Then he closes the cave and flies away, never to return.
nesting
Sphex in the nesting phase
During the nesting phase, females of the genus Sphex build nests on the ground and stock them with orthoptera that will feed their offspring. The behavior of the wasps at this stage has attracted the attention of scholars, when comparing it in the species that make up the genus, through its wide distribution.
When in due time the eggs hatch into larvae , they feed on the paralyzed live prey left behind by their mother. For this reason, there are those who consider the Sphex wasp a “sadistic” insect .
This behavior makes sphex wasps seem intelligent, it is nothing more than a totally rigid, mechanical and routine sequence of actions. Only in appearance is “intelligent”.
When the wasp enters to check that everything is going well, it moves the cricket a few centimeters from the threshold of the cave, the wasp , when it finishes its inspection and leaves, will raise its prey to the top of the mound again, to put it on the threshold of the cave instead of inside it, and will go back in to check that everything is correct.
Sphex with a grasshopper to take him to the cave mound
If while this is happening the operation is repeated and the prey is moved a few centimeters again, the wasp will go back up the mound with the prey, deposit it on the threshold of the cave and go back in to check everything. The experiment has been repeated up to a hundred times and it never occurred to the Sphex to place its prey, once, inside the cave.
The wasp is doomed to follow its genetic algorithm and drag its prey over and over again up the mound to the threshold of the cave.
sphex species
This genus includes a hundred species, some of great size, distributed throughout the world, all nest on land.
sphex maxillosa
From 20 to 25 millimeters in length, it is black with beautiful silvery-white wool; the anterior part of the abdomen, the base of the jaws, the tarsi and in the females the anterior tibiae red; the wings yellow, smoky at the apex, and the median ulnar cell broad. It lives in southern Europe and North Africa .
Spex Occitanica
It measures about 20 millimeters in length, with the pendulum of the black abdomen, the first segment of it the color of rust with an almost triangular black dorsal spot, the second of the same color with a black back and the others entirely black, and the wings. hyaline with smoky apex. He lives in southern Europe .
Sphex Funerarius
Digger wasp of about 2 cm that is characterized by its long tubular waist, the general black color with parts of the abdomen in a mahogany-orange tone and by the wings that cross over the back at rest. He lives alone. It digs a shallow nest in the ground, where it will lay eggs and grow larvae.
Sphex funerarius is found in flowers where it forages for nectar and is both a fearsome predator. To feed its larvae, it captures locusts even larger than itself, which it immobilizes with a paralyzing injection of its stinger and transports to the nest.
sphex pensylvanicos
Sphex pensylvanicus was the subject of the first paper on an insect written by a New World native , when observations made by John Bartram on S. pensylvanicus were presented to the Royal Society in 1749 by Peter Collinson. Sphex pensylvanicus was described by Carl Linnaeus in his 1763 Centuria Insectorum, using material sent to him by Charles De Geer.
- pensylvanicus is an important pollinator of plants , including the milkweed Asclepias syriaca and A. incarnata. Daucus carota , Eryngium yuccifolium, and Melilotus albus have been reported . S. pensylvanicus is one of several species of Sphex to be parasitized by the strepsipteran Paraxenos westwoodi.
Species in Cuba
Four species of the genus Sphex live in Cuba, where Sphex jamaicensis ( Drury) is the most common. Aspects of the nesting behavior of S. jamaicensis, Sphex mandibularis Cresson, and Sphex cubensis (Fernald) were studied at various locations during 1986-1993 .
