Giant Mesquite Bug: Essential Facts and Insights

The Giant Mesquite Bug is an interesting and unique insect that deserves attention for its fascinating characteristics and behaviors. Native to the southwestern United States and Mexico, these large insects can be found on mesquite trees, where they feed on the tree’s sap.

Giant Mesquite Bugs belong to the family Coreidae and have a striking appearance, with vibrant colors and intricate patterns on their wings. They play an important role in their ecosystems, serving as both prey for larger animals and as pollinators of the mesquite trees. These eye-catching insects surely capture the curiosity of anyone who encounters them.

In this article, we will delve deeper into what makes the Giant Mesquite Bug such a fascinating creature. We will explore its physical attributes, life cycle, feeding habits, and the ecological role it plays. So, let’s embark on this journey to discover all there is to know about the Giant Mesquite Bug.

Giant Mesquite Bug Overview

Thasus Neocalifornicus

The Giant Mesquite Bug (Thasus neocalifornicus) is an insect in the family Coreidae, also known as leaf-footed bugs. This bug belongs to the class Insecta and phylum Arthropoda, and has a territorial reach in the southwestern United States and Mexico. It is part of the Pentatomomorpha infraorder and Coreinae subfamily.

Some key features of the Giant Mesquite Bug:

• Large size
• Vivid colors and patterns
• Long, sturdy antennae

Characteristics of this insect include:

• Univoltine life cycle: It has one generation per year
• Herbivorous diet: Mainly feeds on mesquite tree leaves and other vegetation
• Scientific name: Thasus neocalifornicus

The Giant Mesquite Bug can be compared to other bugs in its family. For example:

In conclusion, the Giant Mesquite Bug is an interesting and unique member of the Coreidae family, with distinctive characteristics and territorial reach.

Physical Features and Identifying Qualities

Size and Coloration

• Size: Giant Mesquite Bugs can reach a size of about 2 inches in length.
• Coloration: Their bodies feature various shades of red, brown, black, white, and yellow.

These bugs are known for their striking appearance, making them easy to identify in their natural habitat. They typically have dark bodies accented by colorful markings, such as red, white, and yellow. On their wings, you’ll find pale yellow veins that create a unique pattern.

Antennae and Wings

• Antennae: Giant Mesquite Bugs have long, segmented antennae.
• Wings: They are equipped with two pairs of wings, a larger set for flying and a smaller set for protection.

These insects possess long antennae, which play a crucial role in their sensory perception. Additionally, they have two pairs of wings: a larger set used for flying and a smaller set called hindwings that act as a protective layer.

Habitat and Distribution

Climates and Environments

Giant Mesquite Bugs are predominantly found in areas with a warm and arid climate. They thrive in regions where the mesquite tree grows abundantly. These trees are native to the southwestern United States, Mexico, and parts of Canada. For instance, they are commonly found in the Sonoran Desert, which spans across Arizona and Mexico¹.

• Examples of habitats: Tucson, Pima County, New Mexico, Texas, Baja California Sur, and Sinaloa.
• Features: Arid, warm climate with plenty of mesquite trees.

Territorial Map

The Giant Mesquite Bug can be found in the following areas:

• United States: Arizona, New Mexico, and Texas
• Mexico: Baja California Sur, Sonoran Desert, and Sinaloa
• Canada: Southern regions with mesquite tree presence

Mesquite trees thrive in arid environments, so the distribution of these bugs is heavily influenced by the tree’s habitat². The table below compares the distribution of mesquite trees and Giant Mesquite Bugs:

Life Cycle and Mating

Growth and Development

• The giant mesquite bug goes through five instars during its growth.
• Nymphs hatch in the spring from eggs laid by adult females.

Giant mesquite bug nymphs have a unique appearance:

• Bright colors, such as orange and black, for camouflage.
• Lack of wings, which they develop later in life.

For example, in the early stages, nymphs have a bright orange color that helps them blend in with the mesquite trees they live on.

During their development, giant mesquite bugs go through these changes:

• Growth of wings in later instars.
• Change of colors to blend with their environment.

Reproduction and Offspring

• Males have feathery antennae to detect pheromones emitted by females.
• Females lay eggs in clusters on mesquite trees.

Giant mesquite bug mating habits involve:

• Males searching for receptive females.
• Aerial courtship displays, including wing movements.

Comparison of Males and Females:

Offspring will inherit some characteristics from their parents:

• Camouflage patterns.
• Preference for mesquite trees as habitat.

In conclusion, the life cycle and mating habits of the giant mesquite bug involve growth through instars, development of wings and coloration, and the process of reproduction. These unique insects display fascinating behaviors and adaptations throughout their lives.

Feeding Habits and Prey

Diet and Sap Consumption

Giant Mesquite Bugs are primarily known for their sap-sucking diet. They mainly feed on mesquite tree sap. Some key features of their diet are:

• Preferring new leaves of mesquite trees
• Occasionally consuming seed pods

Their feeding habits can be compared to other sap-sucking insects, like aphids. Here’s a comparison table for your reference:

Economic Impact on Landscape Plants

These bugs can have both positive and negative effects on landscape plants. For instance:

• Giant Mesquite Bugs are mesquite twig girdlers, which can result in the death of mesquite branches
• Their feeding helps control mesquite growth, benefiting other plants that compete for space and resources

However, the economic impact is limited because:

• Mesquite wood and foliage aren’t considered valuable in commercial landscapes
• Giant Mesquite Bugs don’t typically reach pest levels, limiting their impact on overall tree health

There you go! The feeding habits of Giant Mesquite Bugs and their economic impacts are explained in short, easy-to-read paragraphs.

Predators and Defense Mechanisms

Common Threats

Giant Mesquite Bugs, sporting their red and black coloration, face various predators in their environment. The most common of these threats include:

• Birds
• Lizards
• Pallid Bats

Survival Techniques

To deter predators, Giant Mesquite Bugs rely on their vivid colors and unique defense mechanisms. For instance, they:

• Release a pungent odor when threatened
• Aggregate in large groups to visually overwhelm potential attackers

By employing these tactics, these bugs often succeed in withstanding common pests and predators in their environment while maintaining a fascinating and delicate balance within their eco-system.

Comparison of Predators and Defense Mechanisms:

More Information and Resources

Relative Size Comparison

The Giant Mesquite Bug (Thasus neocalifornicus) is part of the Heteroptera suborder in Animalia. It’s important to understand its size relative to other insects:

• Giant Mesquite Bug: Grows up to 1.5 inches in length
• Giant Water Bug: Can exceed 4.5 inches in length

Here’s a comparison table to understand the differences:

Forums

Join an insect forum to discuss, learn, and share information about Giant Mesquite Bugs.

ID Request and Guides

• Request identification help on the iNaturalist platform
• Refer to animal identification guides for more information on taxonomy and taxonomic hierarchy

Features and Characteristics

• Dark-colored with orange, white, or red accents
• Capable of flying, but mostly found on mesquite trees
• Individuals may vary in coloration and size

Territorial Map and Population

The Giant Mesquite Bug’s habitat is primarily within the Southwestern United States and Northern Mexico, wherever mesquite trees are prevalent. Their population fluctuates seasonally.

Common Pests and Solutions

Some common pests related to Giant Mesquite Bugs include:

• Mealybugs: Treat with neem oil or insecticidal soap
• Borers: Use a combination of cultural practices and targeted insecticide application
• Spiders: Maintain cleanliness and remove webs promptly to avoid infestation

Contact and Interaction

Although Giant Mesquite Bugs are not aggressive, it’s important to exercise caution when handling or observing them in their natural habitat to avoid disturbing their ecosystem.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Giant Mesquite Bug Nymphs from Mexico

A Strange and colourful beetle – What is it??
March 21, 2010
I found this cluster of beetles in Cancun Mexico this past week. I found them in the late morning, and I would have been scared by their size (about as long as my thumb) if they weren’t so beautiful! I’d love to know what they are and any extra information about them!
Bekki
Cancun, Mexico

Hi Bekki,
This is not a beetle, but rather a true bug in a different order.  These are immature Giant Mesquite Bug in the genus Thasus, but we are not certain if it is a different species, or a subspecies, or merely a color variation of Thasus neocalifornicus, a species found in Arizona and California that is represented on BugGuide.  We suspect it is either Thasus acutangulus or Thasus gigas, both of which are found in Mexico.  A Threatened Edible Insects in Hidalgo Mexico website indicates the following about Thasus gigas:  “Xamues (Thasus gigas Burm.) (Hemiptera-Coreidae)  Thasus gigas live in the “mezquite” tree (Prosopis juliflora (S) DC), their only host, and are also known as the “mezquite worm”. The species was very abundant in this area, but now that a larger number of adults and larvae are gathered for sale rather than for personal consumption, the abundance of this species has declined. This species is univoltine, and it is collected in the spring [14]. Elderly people in the study area who eat this species, say that they can currently only find few specimens at a time, allowing a one to two month supply, while in the past they could gather enough to feed on for six months. They refer to this species as the “meat we eat”. This insect is greatly appreciated because of its sweet taste, which is rare in the rural areas. After they are gathered, the insects are dried on a griddle, stored in plastic mesh bags, and hung in the kitchen where they provide a daily meal.”  Additional searching leads us to believe that this may be Thasus acutangulus, based on the photo of an immature specimen on the Alex Wild Photography website.  There is also a photo on Flickr.

Letter 2 – Giant Mesquite Bug: adult and nymphs (and it's edible!!!)

Giant Mesquite Bug in Southern Arizona
Hey Bugman!
I found these beautiful bugs at the campground of Sabino Canyon. They were the decorational highlight of a Mesquite tree. What kind of Giant Mesquite Bug might that be? Thanks for any information!
Daniel

Hi Daniel,
These really are called Giant Mesquite Bugs. The species is Thasus acutangulus. The winged specimen in the single photo is an adult, and the nymphs are the brightly colored non-winged individuals.

Hi Daniel,
The large bug Thasus is highly-thought-of in Mexico. I’ve read a good deal about how it’s used there, or at least once was. It’s called “Chamoes” as reported here [under the archaic genus-name Pachilis] and the details include both direct human consumption and as an element of egg-yolk coloration when fed to laying hens. Also mentioned is a crude protein content of 65.4% and fat content of 19.4% Of all the edible insects found in the US this is one of the most sought after — by me! If anyone would like to play the supplier role let’s talk. Thanks,
Dave
www.slshrimp.com

Letter 3 – Giant Mesquite Bugs

beetle in arizona
These beetles were found on a tree (mesquite or acacia) in Tucson AZ… Any idea what they are? Sorry for the poor resolution, they are taken with a cell phone.
Cathie Burgess

Hi Cathie,
Our theory is that a blurry photo is better than no photo. Your image shows one adult Giant Mesquite Bug, Thasus acutangulus, surrounded by a group of immature nymphs. It is the first photo we have received of the adult insect.

Letter 4 – Giant Mesquite Bugs

beetle pics
I’ll be glad if you can identify this guy for me – the more I looked at it as I selected shots to send, the more beautiful I realized it is – what rather Aztec coloring it has! The day I took the photos was the only day I’ve ever seen this kind of beetle down here although I’m sure they are around at other times. If you know of a good Internet link about them please send it to me as well. Thanks!!! Best regards,
Ridge (& Rick) Rickers,
Casa Chuparosa, Cabo Pulmo BCS Mx

Hi Ridge and Rick,
These are Giant Mesquite Bugs, Thasus acutangulus. These are immature specimens. The adults have wings. The wasp is a Paper Wasp

Letter 5 – Giant Mesquite Bug Nymph

Hi: Can you help me out in identifying this bug? Thank you.
Ana

Hi Ana,
This is an immature Giant Mesquite Bug. Adults have fully developed wings and can fly. If you are writing from Arizona, it is Thasus acutangulus. We also get images of this genus from Mexico, but the markings are a bit different. We are not sure if the Mexican population represents a local color variation, a subspecies, or a different species in the same genus.

Letter 6 – Immature Giant Mesquite Bugs

Strange Red & White Cricket (?)
Sun, Jun 21, 2009 at 9:07 AM
Hi –
I am visiting my mom in Rio Rico, AZ (about an hour south of Tucson, AZ) and we found these strange looking red, white and black crickets (?) on a bean plant this morning (06/21/09). I’ve never seen anything like them, especially their antennae. Towards the end of it there is a flattened almost circular area, and then the straight line antennae continues. They seem to be feeding on the beans in the plant, and there must be 30-40 on one plant.
Kristy
Rio Rico, AZ

Hi Kristy,
These are not crickets. Rather they are True Bugs, more specifically, Giant Mesquite Bugs, Thasus neocalifornicus, in the family Coreidae, the Leaf Footed Bugs. They are not feeding on beans, but rather the pods of Mesquite. These are colorful immature nymphs. Once they become winged adults, much of the bright coloration with distinctive markings is covered by the wings. You may read more about them on BugGuide.

Letter 7 – Immature Giant Mesquite Bug

What kind of bug is this?
July 12, 2009
It was quite large. It was found in mid July of 2009.
Joe
It was found in Tuscon, Arizona.

Hi Joe,
It is a Giant Mesquite Bug, Thasus neocalifornicus, and it is not yet mature.  Adults have wings.

Letter 8 – Giant Mesquite Bugs

Southern Arizona
August 5, 2009
My aunt and uncle live in Benson Az. and their trees are full of these beautiful critters
strube1369
Southern Arizona

Dear strube1369,
Your relative’s trees are mesquite trees and this is a Giant Mesquite Bug, Thasus neocalifornicus.  The immature nymphs are even more colorful.

Letter 9 – Giant Mesquite Bug Nymph

what is this?
Location: Southern Arizona
November 18, 2010 5:27 pm
I found this bug while working in Arizona this summer and want to know what it is.
Thanks!
Signature: michael

Dear Bugman,
I did some research on your site and found that I have found a Giant Mesquite bug nymph.
Thanks for such a great resource and maybe the photo can help to add to your amazing database.
Best,
Michael

Hi Michael,
We are very happy to hear you were able to self-identify your Giant Mesquite Bug Nymph.

Letter 10 – Giant Mesquite Bugs from Costa Rica

beetle found in costa rica
Location: Costa Rica
November 21, 2010 4:53 pm
Hello,
these beetles were seen in Costa Rica but we have been unable to identify them.
Pleeeeeese help as it is driving us mad.
Signature: Mrs G Dyer

Dear Mrs G Dyer,
These are not beetles, but rather, immature Leaf Footed Bugs in the genus Thasus.  The Giant Mesquite Bug, Thasus neocalifornicus, that is found in the Southwest portion of North America is very similar.  We posted a similar photo from Mexico recently, and that posting has much information.  According to BugGuide:  “Dr. James Hogue (Cal State Northridge) pointed out that this genus has been revised (please see references below; HW). T. acutangulus is present only in Mexico, Guatemala, Belize (formerly British Honduras), and Costa Rica. The records from the United States are misidentifications (per Brailovsky, Schaefer, et al. 1994; see reference below – HW)   T. neocalifornicus is the only species of this genus that occurs in the U.S.A.  It is close to T. gigas from Mexico, and T. acutangulus (see distribution notes above).”

Letter 11 – Immature Giant Mesquite Bug

colourful bug
Location: jalisco mexico – lake chapala north shore mountains
June 16, 2011 11:27 am
this bug was +/- 1.5” long and we saw him on a high dry trail above lake chapala in jaliso mexico. the rainy season has just arrived
Signature: jstanley

Dear jstanley,
We have to admit that your email was the very last one we opened this morning but we did not have the time to post it before cleaning up some matters at LACC where we work.  This Giant Mesquite Bug nymph is surely a colorful creature.  Here is a BugGuide page on a species found in the Southwestern States of the US, Thasus neocalifornicus, that is also found in Mexico.

Very cool! Thank-you so much for replying and so promptly.  I am sharing this information with our hiking pals and have turned him into my screen saver. It’s easy to see where some of the beautiful whimsical Mexican masks ideas find their inspiration!.

Letter 12 – Giant Mesquite Bug Nymph from Mexico

Subject: Colorful Beetle seen in Central Mexico
Location: Tepoztlan, Morelos, Mexico
September 22, 2012 7:55 pm
Hi there! In April, 2010, I was in Mexico, in Tepoztlan, in the state of Morelos, hiking up a hill to some ruins when I came across this very ornate and colorful bug. There were actually many of them along the trail of this hike. They looked like jewels! The weather at the time was super hot and dry…
Signature: What a great idea for a website!!

Your insect is a member of the Leaf Footed Bug family Coreidae rather than a beetle.  It resembles a species found in the southwest portions of the U.S. as well as in Mexico, the Giant Mesquite Bug, Thasus neocalifornicus, but the coloration is different.  We believe this is another member of the genus.  Here is a similar individual from our archives.  The Things Biological website has an identically colored specimen identified as a Giant Mesquite Bug, and the site goes on to state:  “These nymphs are enormous, each being roughly the size of my thumb. I have never encountered them before and was astounded by their size and abundance. Adults and nymphs can be found on mesquite trees during the summer. The nymphs congregate on the pods, drinking plant fluids, while the adults feed on fluids from both the pods and young twigs.  The young advertise their bad taste with their brilliant colors, which are further emphasized by their tendency to aggregate.”  We are inclined to believe that the genus is correct, but that the species may be misidentified.  The images on BugGuide support that belief.  Though we are confident the genus is correct, we cannot conclusively provide you with the species name. 

Letter 13 – Giant Mesquite Bug nymphs invade school in Belize

Subject: School infestation
Location: Northern Belize (tropical marine climate)
November 15, 2012 7:16 pm
We are suddenly have great numbers of the pictured bugs at the village school. No one seems sure what it is or if it is dangerous to the children.
Signature: Peter

Hi Peter,
You have nothing to fear from this proliferation of Giant Mesquite Bug nymphs.  They pose no danger to the school or the children.  They are edible and they are commonly eaten by the indigenous people of Mexico.

Thank you for your help.  Sound like we could have saved a bit on the lunch program. Peter

When we eat something, we like it to look good, and this is one good looking nymph.  Winged adults don’t look as tasty.  We will contact David Gracer to see if he can provide any information on how they taste.

Letter 14 – Giant Mesquite Bug nymph from Panama

Subject: bug in Panama garden
Location: Bqquete, Chiriqui province, Panama
December 29, 2012 10:42 pm
I watched this for ages in the garden in Boquete , there were 4 of the same on the one branch and did not seem interested in going anywhere even when I got really close. they were about the size of a thumbnail. I have never seen anything like this before and would love to know what it is, is it poisonous etc.
Signature: Thanks, Carol

Hi Carol,
This colorful individual is an immature Giant Mesquite Bug in the genus Thasus.  Not only is it not poisonous, it is actually edible.

Letter 15 – Giant Mesquite Bugs from Mexico

Subject: Mexican Mesquite Bug
Location: Tulum, Quintana Roo Mexico
March 17, 2013 7:56 am
You have a couple of picture of these identified as nymphs of Mexican and Costa Rican Mesquite Beetles. I am enclosing a picture taken at Tulum Mexico in March 4th in which there appear to be two stages of the bug – does this help to identify the species?
Signature: Gord Wakeling

Dear Gord,
These are Giant Mesquite Bugs in the genus Thasus, but we cannot say for certain which species it is.

Letter 16 – Giant Mesquite Bug nymph from Guatemala

Subject: Beautiful insect from Guatemala
Location: Guatemala
May 25, 2013 7:53 pm
My daughter took this photo in Guatemala of what I think must be the most beautiful insect in the world. I am curious to know more about this insect, and what function its beautiful markings might serve. I tried to find out more about it through Google images, and found a photo of another specimen, but with no useful information (https://contest.thesca.org/sites/default/files/imagecache/large/IMG_2098.JPG ) Can you tell me about this insect?
Signature: Ed Max

Hi Ed,
This is the nymph of a Leaf Footed Bug in the genus Thasus, and they are commonly called Giant Mesquite Bugs.  They are edible, which is interesting since the color would most likely be described as aposomatic or warning coloration.  We have not been successful in identifying this particular insect to the species level, but we are confident that the genus Thasus is correct.

Letter 17 – Giant Mesquite Bug Nymphs from Mexico

Subject: What kind?
Location: Mexico, Quintana Roo, Yucatán península
December 16, 2013 8:25 pm
Hi,
I found these in Mexico – in Quintana Roo on top of a 40 m pyramid and I would like to know what they are, as their colours are incredible.
Signature: jana

Hi jana,
These colorful guys are immature Giant Mesquite Bugs in the genus Thasus.  We have only one species north of the Mexican border, but Mexico and Central America are hosts to several other species in the genus.

Hi,
thank you very much for letting me know.
Jana

Letter 18 – Giant Mesquite Bugs from Panama

Subject: stages of the same beetle?
Location: Chiriqui province, Panama
December 26, 2013 5:55 pm
The first photo was taken on 12/17, the second on 12/25. Are all of these beetles the same kind, just in various stages of development or is the color difference related to sex?
Signature: Linda

Hi Linda,
Your assessment of the insects in these photos is partially correct and partially incorrect.  You are correct that they are various stages of development of the same species, however these are Big Legged Bugs or Leaf Footed Bugs in the family Coreidae, not beetles.  Beetles undergo complete metamorphosis, and they transform from grubs that bear no resemblance to the adults.  True Bugs undergo incomplete metamorphosis, and nymphs look similar in structure to adults, though they might have different colors and markings.  Your Big Legged Bugs are Giant Mesquite Bugs in the genus Thasus, most likely Thasus acutangulus.

Thank you once again. Fascinating. Very helpful.

Letter 19 – Immature Giant Mesquite Bug from Brazil

Subject: Insect identification
Location: Rio de janeiro, brazil
December 31, 2013 6:48 am
HI,
WOULD YOU HELP ME TO KNOW WHAT KIND OF BUG IS THIS?
IT HAS HALF OF AN INCH,
IT IS VERY BEAUTIFUL, AND I DON T KNOW IF IT BITES.
THANKS
Signature: ANTONIO

Dear Antonio,
This is an immature Giant Mesquite Bug in the genus Thasus, and they are much more colorful before they metamorphose into adults.

Letter 20 – Immature Giant Mesquite Bug

Subject: What is this bug?
Location: El Pueblito, Corregidora, Queretaro, Mexico.
April 17, 2014 1:56 pm
I found this little bug over my leg when I was sitting on a bench outside my house. Ive never seen this kind of insect befere so I decided to take it home to take a few shots of it. It almost look like somebody painted on it, its really beautiful. I hope its not poisonous because I threw it away very close from home.
Signature: Oscar Vazquez

Hi Oscar,
The bold colors and markings on this Giant Mesquite Bug nymph make it quite unforgettable. 

Letter 21 – Immature Giant Mesquite Bug

Subject: ID Bug
Location: Tucson Arizona
June 6, 2014 1:14 pm
This bug was found on a tree at a commercial office complex in Tucson, AZ during the month of June, 2014.
Thank you!
Signature: Matt from Sahuarita Arizona

Hi Matt,
This is an immature Giant Mesquite Bug.

Letter 22 – Giant Mesquite Bug Nymphs from Mexico

Subject: Colourful bugs from South Mexico
Location: South Mexico – jungle
September 23, 2014 5:09 am
Further to my previous email I wondered if you could identify this very colourful bug? I have tried but to no avail. Searching for Mexican insects almost always leads to sites about eating them. I imagine these are probably found in parts of the US as well but I have been unsuccessful none the less. This type of bug is completely beyond my normal range of knowledge… it kind of looks like a really fat leaf-footed/assassin hybrid!
Any ideas?
Signature: Long time avid WTB reader

Dear Long time avid WTB reader,
These colorful nymphs are immature Giant Mesquite Bugs in the genus Thasus.  Interestingly, this is an edible species and we are surprised you didn’t find it on the edible sites you searched.  There is a North American species of Giant Mesquite Bug that is found primarily in Arizona.

Letter 23 – Immature Giant Mesquite Bugs from Colombia

Subject: Strange Bug
Location: Bogotá, 2.600 mts above sea level
February 8, 2015 10:24 pm
Dear Mr. Bugman,
I found these strange bugs in my garden, lots of them in a tree (Alcaparro in spanish). Nobody can tell me what kind of bugs they are, if harmful or poisonous. I live in Bogotá, Colombia. S.A. Will
you please tell me about it?
Thank you,
Signature: Silvia Riaño

Dear Silvia,
Though your image is blurry, we are pretty confident these are Giant Mesquite Bugs in the genus Thasus.  They are not poisonous and we even received a report that they are edible.

Letter 24 – Giant Mesquite Bug Nymph from Guatemala

Subject: id this guy, please
Location: lago atitlan, solola, guatemala
April 21, 2016 8:28 am
hello – i saw this bug on my porch at lago atitlan, solola, guatemala please help me with the name. thanks!
Signature: dale

Dear Dale,
This colorful critter is a  Giant Mesquite Bug nymph,Thasus neocalifornicus.  Here is an image on BugGuide for verification.  Immature Giant Mesquite Bugs often form large aggregations on the food plant. 

Letter 25 – Giant Mesquite Bug nymphs

Subject: Beetle in Vail, AZ
Location: Vail, AZ
June 20, 2016 9:05 am
Can you help I’d this beetle?
Signature: Cindy

Dear Cindy,
These are NOT beetles.  They are immature Giant Mesquite Bugs, Thasus neocalifornicus, and according to BugGuide, they feed on:  “The green pods of Mesquite (Prosopis spp.), notably the non-native P. velutina (Chilean, Velvet Mesquite) and the native P. glandulosa (Honey Mesquite).”

Letter 26 – Giant Mesquite Bug Nymph from Mexico

Subject:  African Warrior Mask Bug?
Geographic location of the bug:  Guadalajara, Jalisco, Mexico
Date: 02/23/2018
Time: 02:56 PM EDT
Your letter to the bugman:  Hello Bugman, this is my 3rd bug I’ve submitted!
This one is from a friend that lives in Guadalajara.
She sent it to me to get more info.
Have at it!
Thanx!
How you want your letter signed:  Mike Coniglio

Dear Mike,
This is the nymph of a Giant Mesquite Bug in the genus Thasus.  Based on iNaturalist, we believe your individual is Thasus gigas, and iNaturalist indicates the Spanish name is Chinche gigante xamuis.

Letter 27 – Giant Mesquite Bugs from Mexico

Subject:  Insects
Geographic location of the bug:  Mexico, Yucatan peninsula,
Date: 03/28/2019
Time: 08:52 AM EDT
Your letter to the bugman:  I found this group of insects all huddled up together on a branch in early February this year while on vacation in Mexico.  I have no idea what they are but I was fascinated by them.  I also wondered why they were all together like this.
Thanks a lot.
How you want your letter signed:  Paul

Dear Paul,
These are Giant Mesquite Bug nymphs in the genus Thasus.

Letter 28 – Giant Mesquite Bug Nymph from Mexico

Subject:  Mexican beetle
Geographic location of the bug:  Cima de Tepozteco
Date: 04/19/2019
Time: 11:46 AM EDT
Your letter to the bugman:  Looking to identify this photographed by a friend. Apparently known as escarabajo but I’m guessing that’s a generic name for several beetles.
How you want your letter signed:  Cliff

Dear Cliff,
This is not a Beetle.  It is a Giant Mesquite Bug nymph, and they are frequently found feeding in groups.

Hi Daniel
Thank you very much for your prompt reply and identification. Please excuse my basic ignorance of what is a beetle or not.
A friend of mine took that photo, and from a British perspective, it looks very unusual. Several of us will be glad to know.
Best wishes
Cliff

No problem Cliff.  That is why we are still here after 17 years.