Dasymutilla occidentalis

Last updated

Dasymutilla occidentalis
Dasymutilla occidentalis (female).jpg
Female
Dasymutilla occidentalis (male) 6184404.jpg
Male
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Mutillidae
Genus: Dasymutilla
Species:
D. occidentalis
Binomial name
Dasymutilla occidentalis
Synonyms [1]

Mutilla occidentalisLinnaeus, 1758

Dasymutilla occidentalis (red velvet ant, eastern velvet ant, cow ant or cow killer) [2] [3] [4] is a species of parasitoid wasp that ranges from Connecticut to Kansas in the north and Florida to Texas in the south. Adults are mostly seen in the summer months. [5]

Contents

The eastern velvet ant is the largest of the velvet ant species in the eastern United States, attaining an approximate length of 0.75 in (1.9 cm). Adults display aposematic coloration, consisting of black overall coloring with an orange-red pattern on the dorsal surface of the thorax and abdomen.

Characteristics and description

Commonly mistaken for an ant because of its appearance and its common name, it is a parasitoid wasp species in which the females are wingless, as is true for all females of Mutillidae. It can be recognized by its distinctive coloring, black with bright red on the upper side of the head, thorax, and abdomen. [4] They are quick-moving and often take a defensive posture when threatened. Unlike the females, males have dark, translucent wings and do not possess a stinger. [6] [2] [3]

Ecology

Dasymutilla occidentalis plays an ecological role as parasites, and prey. [7]

Defense

Dasymutilla species have multiple defensive strategies, but are best known for their extremely painful sting, ranked 3 out of 4 on the Schmidt's sting pain index, earning them the nickname of "cow killer". [6] [8] Cow killer defenses include a thickened exoskeleton, the ability to run fast and evasively, warning coloration, stridulatory warning sounds, a chemical secretion, and venom. [9] Both sexes make a squeaking noise (stridulation) to warn potential predators (another form of aposematism in females, and automimicry in males). [9] When stridulating, velvet ants rub their abdominal segments together in a rapid fashion. This is different than stridulation seen in insects such as crickets, in which the leg structures are rubbed against the abdomen. [10]

D. occidentalis and related species are well known for their Mullerian mimicry. Mullerian mimicry occurs when species with pre-existing defenses adopt similar colorations and patterns to increase the fitness of both all species involved. North American velvet ant species comprise one of the most intricate Mullerian mimicry rings in the natural world, being divided into eight separate rings of mimicry. [10] Their behavior and coloring has been used to study how aposematic coloration works in the wild. [11]

Reproduction and life cycle

Like most wasp species, velvet ants live solitary lives. Males take to the air to detect pheromones released by females. Males will fly towards female stridulation sounds as well. [12] Once a receptive female is located, the male will carry the female in his mandibles and move her to place he deems "safe" to mate. These mating spaces are often shaded and away from potential mating competitors. [12] Both males and females stridulate during the mating process. Once the mating process is finished, the female begins looking for eggs and larvae of host species. [12] Females are believed to mate only once in their lifetime. [12]

After mating, females seek out the brood cells of Eastern cicada killers and horse guard wasps as well as other large ground-nesting members of Crabronidae, where they sneak into the nest and deposit an egg onto a host larva. The egg quickly hatches into a white, legless grub, which consumes the host larva and goes through several larval stages prior to pupation. [8] Pupation typically takes 23 days. [12]

Related Research Articles

<span class="mw-page-title-main">Mimicry</span> Imitation of another species for selective advantage

In evolutionary biology, mimicry is an evolved resemblance between an organism and another object, often an organism of another species. Mimicry may evolve between different species, or between individuals of the same species. Often, mimicry functions to protect a species from predators, making it an anti-predator adaptation. Mimicry evolves if a receiver perceives the similarity between a mimic and a model and as a result changes its behaviour in a way that provides a selective advantage to the mimic. The resemblances that evolve in mimicry can be visual, acoustic, chemical, tactile, or electric, or combinations of these sensory modalities. Mimicry may be to the advantage of both organisms that share a resemblance, in which case it is a form of mutualism; or mimicry can be to the detriment of one, making it parasitic or competitive. The evolutionary convergence between groups is driven by the selective action of a signal-receiver or dupe. Birds, for example, use sight to identify palatable insects and butterflies, whilst avoiding the noxious ones. Over time, palatable insects may evolve to resemble noxious ones, making them mimics and the noxious ones models. In the case of mutualism, sometimes both groups are referred to as "co-mimics". It is often thought that models must be more abundant than mimics, but this is not so. Mimicry may involve numerous species; many harmless species such as hoverflies are Batesian mimics of strongly defended species such as wasps, while many such well-defended species form Müllerian mimicry rings, all resembling each other. Mimicry between prey species and their predators often involves three or more species.

<span class="mw-page-title-main">Mutillidae</span> Family of wasps

The Mutillidae are a family of more than 7,000 species of wasps whose wingless females resemble large, hairy ants. Their common name velvet ant refers to their resemblance to an ant, and their dense pile of hair, which most often is bright scarlet or orange, but may also be black, white, silver, or gold. Their bright colors serve as aposematic signals. They are known for their extremely painful stings,, and has resulted in the common name "cow killer" or "cow ant" being applied to the species Dasymutilla occidentalis. However, mutillids are not aggressive and sting only in defense. In addition, the actual toxicity of their venom is much lower than that of honey bees or harvester ants. Unlike true ants, they are solitary, and lack complex social systems.

<span class="mw-page-title-main">Yellowjacket</span> Common name for two genera of wasps

Yellowjacket or yellow jacket is the common name in North America for predatory social wasps of the genera Vespula and Dolichovespula. Members of these genera are known simply as "wasps" in other English-speaking countries. Most of these are black and yellow like the eastern yellowjacket and the aerial yellowjacket ; some are black and white like the bald-faced hornet. Some have an abdomen with a red background color instead of black. They can be identified by their distinctive markings, their occurrence only in colonies, and a characteristic, rapid, side-to-side flight pattern prior to landing. All females are capable of stinging. Yellowjackets are important predators of pest insects.

<span class="mw-page-title-main">Apocrita</span> Suborder of insects containing wasps, bees, and ants

Apocrita is a suborder of insects in the order Hymenoptera. It includes wasps, bees, and ants, and consists of many families. It contains the most advanced hymenopterans and is distinguished from Symphyta by the narrow "waist" (petiole) formed between the first two segments of the actual abdomen; the first abdominal segment is fused to the thorax, and is called the propodeum. Therefore, it is general practice, when discussing the body of an apocritan in a technical sense, to refer to the mesosoma and metasoma rather than the "thorax" and "abdomen", respectively. The evolution of a constricted waist was an important adaption for the parasitoid lifestyle of the ancestral apocritan, allowing more maneuverability of the female's ovipositor. The ovipositor either extends freely or is retracted, and may be developed into a stinger for both defense and paralyzing prey. Larvae are legless and blind, and either feed inside a host or in a nest cell provisioned by their mothers.

<span class="mw-page-title-main">Tarantula hawk</span> Common name for two genera of wasps

A tarantula hawk is a spider wasp (Pompilidae) that preys on tarantulas. Tarantula hawks belong to any of the many species in the genera Pepsis and Hemipepsis. They are one of the largest parasitoid wasps, using their sting to paralyze their prey before dragging it to a brood nest as living food; a single egg is laid on the prey, hatching to a larva which eats the still-living host. They are found on all continents other than Europe and Antarctica.

<i>Sphecius speciosus</i> Species of wasp

Sphecius speciosus, often simply referred to as the cicada killer or the cicada hawk, is a large, solitary digger wasp species in the family Crabronidae. The name may be applied to any species of crabronid that preys on cicadas, though in North America, it is typically applied to this species, also referred to as the eastern cicada killer in order to further differentiate it from the multiple other examples of related wasp species. Sometimes, they are called sand hornets, although they are not hornets, which belong to the family Vespidae. This species can be found in the Eastern and Midwest U.S. and southwards into Mexico and Central America. They are so named because they hunt cicadas and provision their nests with them. Cicada killers exert a measure of natural control on cicada populations, and as such, they may directly benefit the deciduous trees upon which the cicadas feed.

<span class="mw-page-title-main">Batesian mimicry</span> Bluffing imitation of a strongly defended species

Batesian mimicry is a form of mimicry where a harmless species has evolved to imitate the warning signals of a harmful species directed at a predator of them both. It is named after the English naturalist Henry Walter Bates, who worked on butterflies in the rainforests of Brazil.

<span class="mw-page-title-main">Müllerian mimicry</span> Mutually beneficial mimicry of strongly defended species

Müllerian mimicry is a natural phenomenon in which two or more well-defended species, often foul-tasting and sharing common predators, have come to mimic each other's honest warning signals, to their mutual benefit. The benefit to Müllerian mimics is that predators only need one unpleasant encounter with one member of a set of Müllerian mimics, and thereafter avoid all similar coloration, whether or not it belongs to the same species as the initial encounter. It is named after the German naturalist Fritz Müller, who first proposed the concept in 1878, supporting his theory with the first mathematical model of frequency-dependent selection, one of the first such models anywhere in biology.

<span class="mw-page-title-main">Aposematism</span> Honest signalling of an animals powerful defences

Aposematism is the advertising by an animal, whether terrestrial or marine, to potential predators that it is not worth attacking or eating. This unprofitability may consist of any defenses which make the prey difficult to kill and eat, such as toxicity, venom, foul taste or smell, sharp spines, or aggressive nature. These advertising signals may take the form of conspicuous coloration, sounds, odours, or other perceivable characteristics. Aposematic signals are beneficial for both predator and prey, since both avoid potential harm.

<i>Hyalophora cecropia</i> Species of moth

Hyalophora cecropia, the cecropia moth, is North America's largest native moth. It is a member of the family Saturniidae, or giant silk moths. Females have been documented with a wingspan of five to seven inches or more. These moths can be found all across North America as far west as Washington and north into the majority of Canadian provinces. Cecropia moth larvae are most commonly found on maple trees, but they have also been found on cherry and birch trees among many others. The species was first described by Carl Linnaeus in his 1758 10th edition of Systema Naturae.

<span class="mw-page-title-main">Parasitoid wasp</span> Group of wasps

Parasitoid wasps are a large group of hymenopteran superfamilies, with all but the wood wasps (Orussoidea) being in the wasp-waisted Apocrita. As parasitoids, they lay their eggs on or in the bodies of other arthropods, sooner or later causing the death of these hosts. Different species specialise in hosts from different insect orders, most often Lepidoptera, though some select beetles, flies, or bugs; the spider wasps (Pompilidae) exclusively attack spiders.

<i>Phidippus johnsoni</i> Species of spider

Phidippus johnsoni, the red-backed jumping spider or Johnson jumping spider, is one of the largest and most commonly encountered jumping spiders of western North America. It is not to be confused with the unrelated and highly venomous redback spider.

<i>Dasymutilla</i> Genus of wasps

Dasymutilla is a wasp genus belonging to the family Mutillidae. Their larvae are external parasites to various types of ground-nesting Hymenoptera. Members of this genus are highly variable in sting intensity, ranging from a 1 (D. thetis) to a 3 in the Schmidt sting pain index.

<i>Dasymutilla gloriosa</i> Species of wasp

Dasymutilla gloriosa, sometimes referred to as the thistledown velvet ant, is a member of the genus Dasymutilla. Only females are wingless, as in other mutillids. Compared to other mutillids, it is mid-sized, being larger than some of the smallest known species like Dasymutilla vesta but smaller than some of the largest known species like Dasymutilla klugii. It ranges from Utah, Nevada, California, Arizona, New Mexico, Texas and south into Mexico.

<i>Jalmenus evagoras</i> Species of butterfly

Jalmenus evagoras, the imperial hairstreak, imperial blue, or common imperial blue, is a small, metallic blue butterfly of the family Lycaenidae. It is commonly found in eastern coastal regions of Australia. This species is notable for its unique mutualism with ants of the genus Iridomyrmex. The ants provide protection for juveniles and cues for adult mating behavior. They are compensated with food secreted from J. evagoras larvae. The ants greatly enhance the survival and reproductive success of the butterflies. J. evagoras lives and feeds on Acacia plants, so butterfly populations are localized to areas with preferred species of both host plants and ants.

<span class="mw-page-title-main">Wasp</span> Group of insects

A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. The wasps do not constitute a clade, a complete natural group with a single ancestor, as bees and ants are deeply nested within the wasps, having evolved from wasp ancestors. Wasps that are members of the clade Aculeata can sting their prey.

<i>Mutilla europaea</i> Species of wasp

Mutilla europaea, the large velvet ant, is a species of parasitoid wasps belonging to the family Mutillidae. It is a parasitoid on various species of bumblebees and is found in Europe, Asia, and North Africa.

<i>Pepsis grossa</i> Species of wasp

Pepsis grossa is a very large species of pepsine spider wasp from the southern part of North America, south to northern South America. It preys on tarantula spiders, giving rise to the name tarantula hawk for the wasps in the genus Pepsis and the related Hemipepsis. Only the females hunt, so only they are capable of delivering a sting, which is considered the second most painful of any insect sting; scoring 4.0 on the Schmidt sting pain index compared to the bullet ant's 4.0+. It is the state insect of New Mexico. The colour morphs are the xanthic orange-winged form and the melanic black winged form. In northern South America, a third form, known as "lygamorphic", has a dark base to the wings which have dark amber median patches and a pale tip.

<i>Euspinolia militaris</i> Species of wasp

Euspinolia militaris is a species of wasp in the family Mutillidae. Though it is a wingless wasp, it has sometimes been referred to by the name panda ant.

<i>Dasymutilla eminentia</i> Species of wasp

Dasymutilla eminentia is a species of parasitoid wasp in the family Mutillidae. Members of this family of wasps are often mistaken for true ants, especially since females are wingless. Unlike ants, however, their bodies are covered by a dense pile of velvet-like hair, and they lack petiole nodes.

References

  1. "Dasymutilla occidentalis (Linnaeus)". Global Biodiversity Information Facility . Retrieved 11 May 2023.
  2. 1 2 "Species Dasymutilla occidentalis". Bugguide. Iowa State University. Retrieved September 12, 2011.
  3. 1 2 "Red Velvet Ant or "Cow Killer"". Texas AgriLife Extension Service: A Field Guide To Common Texas Insects. Texas A&M University. Archived from the original on September 2, 2011. Retrieved September 12, 2011.
  4. 1 2 "Red velvet ant; cow killer". Arthropod Museum. University of Arkansas: Division of Agriculture. Archived from the original on May 26, 2012. Retrieved September 12, 2011.
  5. Smith, Caleb. "Dasymutilla occidentalis". Animal Diversity Web. Retrieved 2024-04-20.
  6. 1 2 Jackman, John. "Venomous Terrestrial Animals of Texas" (PDF). Texas A&M University System.{{cite journal}}: Cite journal requires |journal= (help)
  7. Gall, B. G.; Spivey, K. L.; Chapman, T. L.; Delph, R. J.; Brodie Jr, E. D.; Wilson, J. S. (2018). "The indestructible insect: Velvet ants from across the United States avoid predation by representatives from all major tetrapod clades". Ecology and Evolution. 8 (11): 5852–5862. doi:10.1002/ece3.4123. PMC   6010712 . PMID   29938098.
  8. 1 2 "Velvet Ant (Cow Killer Ant) | Nebraska Extension in Lancaster County". lancaster.unl.edu. Retrieved 2023-09-27.
  9. 1 2 Schmidt, Justin O.; Blum, Murray S. (1977). "Adaptations and responses of Dasymutilla occidentalis (Hymenoptera: Mutillidae) to predators". Entomologia Experimentalis et Applicata. 21 (2): 99–111. doi:10.1111/j.1570-7458.1977.tb02663.x. ISSN   1570-7458. S2CID   83847876.
  10. 1 2 "Velvet ants: flamboyant and fuzzy with extreme PPE". www.nhm.ac.uk. Retrieved 2024-02-21.
  11. Wilson, Joseph S.; Williams, Kevin A.; Pitts, James P. (2010). "Preliminary Assessment of Velvet Ant (hymenoptera: Mutillidae) Diversity in the Deserts of Southern California". Western North American Naturalist. 70 (2): 224–232. doi:10.3398/064.070.0209. ISSN   1527-0904. JSTOR   41717897.
  12. 1 2 3 4 5 Smith, Caleb. "Dasymutilla occidentalis". Animal Diversity Web. Retrieved 2024-02-21.