caterpillars may provide you with many virgin simple hairs (you need a hand lens to see this). females and the means to conduct an interest- Together with ants, bees and wasps form an ing census of male moths in your area. Place evolutionary lineage referred to by taxonomists female moths (usually distinguishable from as the aculeate, or “stinging,” Hymenoptera; males of the same species by having narrower, the stinger is called an aculeus. Among the less comb-like antennae and larger, swollen ab- aculeate hymenopterans, only females sting. domens) into small mesh or wire cages; posi- The stinger evolved from the ovipositor, or egg- tion the cages along a trail, near a forest clear- laying tube. Sonoran Desert bees range in size ing, or on your porch; then observe. If males from the world’s smallest bee, Perdita minima, of this species are about, they should find their which is less than 0.08 inches (2 mm) long, to way to the cages in short order. When do they carpenter bees (genus Xylocopa), gentle giants arrive? How abundant are they in suburban with body lengths of almost 1 ½ inches (40 areas, as compared with rural habitats? Do mm) long that can weigh almost 0.04 ounces (1 males from more than one species arrive at the g). Our native bees burrow into the ground, cre- cages? If you are interested in moth breeding, ate nests, or use abandoned tunnels inside hol- this is an excellent way to attract wild mates low, pithy, dried stems or abandoned tunnels and begin the life cycle anew. left by wood-boring beetles. A few leafcutter bees (a grouping called anthidiines) construct small pebble and resin nests attached to twigs Bees of creosotebushes and other plants. All bees are Stephen L. Buchmann herbivorous except for parasitic forms that prey 309-352 116269 4/25/00 3:45 PM Page 344 Page PM 3:45 4/25/00 116269 309-352 Order: Hymenoptera on other bees. Herbivorous bees feed on pollen, nectar, and oils offered as floral rewards by flow- Families: Andrenidae, Apidae (includes all ering plants. Bright metallic mason bees find members of the former family Anthophoridae), Colletidae, Halictidae, Megachilidae, unoccupied beetle burrows in dead trees and Melittidae, Oxaeidae bring back mud to form partitioning cell walls between their larvae. Some bees are cleptopara- Common Sonoran Desert genera: Agapostemon, sites on other bees; cuckoo bees, for instance, Andrena, Anthidium, Anthophora, Apis, region our in bees social Highly bees Desert Sonoran our of Most sneak into the nests of other bees to lay their Ashmeadiella, Bombus, Centris, Coelioxys,and bee honey introduced the include with year, per generation one but have Colletes, Diadasia, Epeolus, Exomalopsis, bumblebees yellow eggsand whenblack thenative nestingthe femalespring isthe away,with similaremerging usually adults Halictus, Heriades, Heteranthidium, Bumblebee . to a cowbirdBombus genus laying the in an egg in another Some bird’sblooms. nest wildflower summer or Hylaeus, Megachile, Melecta, Melissodes, estab- nature, in and lettingannual are the fostercolonies mom rear 3 hereven chick.or 2 Most have however, species, Nomadopsis, Nomia, Osmia, Panurginus,queen bees havealready-inseminated an solitaryby lished lifestyleslife in whichtypical a females In year. per generations Peponapis, Perdita, Psithyrus, Sphecodes,in retreat Stelis,winter her act alonefrom to constructemerges who and provisionmate females nests,and butmales adult history, Svastra, Tetraloniella, Triepeolus, Xenoglossa,nest mouse suitable there a arefinds alsoand semi-socialspring forms,natal suchtheir asfrom the fa- emergence after soon Xeromelecta, Xylocopa which in cavity miliar largeunderground blackother carpenteror beesprovision ( Xylocopaand vari-construct Females cells. Spanish names: abeja (bee), jicote, abejorroher than larger is queen The nest. to larvae the and eggs, lay and nests (bumble bee, carpenter bee) after eggs the all lays and daughters, under- rapidly develop Bees make up a highly diverse group small in a the initially, produced, has she cooler During ground. brood of workers. Males and Males workers. of brood usually larvae the months ­Sonoran Desert Region. Superficially, bees queens are produced late in late produced are queens resting a in stay (especially the parasitic bees known as the cuckoo in and season the dia- or condition, bees) resemble some wasps, except thatmate, bees They are cycle. colony the either at , pause usually hairier and fatter, and they possessthe and spedie, - males the adult pharate the or prepupal cialized structures for carrying pollenspend back toqueens inseminated just stage pupal (the stage © their nests. Bees also have branched (plumose“hiber- )winter and fall the Martin Jeff to molt final the to prior hairs on their bodies, which distinguishesthe until ground below nating” until proper) adult the them from wasps, which have unbranched spring. next bumble beeBumblebee spring following the Farther south in Sonora, in south Farther when summer or eio(erAao) extremely Alamos), (near Mexico metamorphoses their complete they 310 Animals many with colonies in live bees social adults. as emerge and thousands of individuals—the so- individuals—the of thousands called “stingless bees,” in the genera the in bees,” “stingless called EHAVIOR B OCIAL S . These queens are queens These . Trigona and Melipona desert our of number small relatively A full swollen abdomens with , physogastric indi- sociality Bee social. truly are bees UC_ASDM-S2--TEXT_PT3.indd 310 9/9/15 2:18 PM of eggs. They are not able to fly once fly to able not are They eggs. of evolutionary species’ these that cates they begin laying eggs, and never leave never and eggs, laying begin they their of those from diverged have paths the colony again. Thus, these social these Thus, again. colony the some of case the In ancestors. solitary bees represent a still greater caste caste greater still a represent bees Halictidae), family (the bees sweat differentiation between queens and queens between differentiation the in females other like looks queen a workers. Stingless bees store as much as store bees Stingless workers. having in differs she though colony, as several quarts (liters) of honey in honey of (liters) quarts several as or may She ovaries. developed highly waxen storage pots that look like like look that pots storage waxen elicit that pheromones secrete not may clusters of grapes. Indigenous peoples Indigenous grapes. of clusters her in behavior grooming and feeding who find these nests within hollow within nests these find who eggs the all lays queen The daughters. trees sometimes transport the hives the transport sometimes trees colonies bee Sweat colony. the within back to their villages, where they tend they where villages, their to back few a of consisting small, usually are the bees and routinely harvest their harvest routinely and bees the hundred few a most at or dozen honey and beeswax. and honey individuals.

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DISTRIBUTION flowers. Not only are we dependent There are at least 45 genera in 7 fami- upon these “forgotten pollinators” for lies, and perhaps as many as 1000 over a third of our food, but for other Africanized Bees species of bees distributed within the products as well. Cotton cloth is a SonoranThe infamous Desert Africanized bioregion. honey Unlike bee (sometimesproduct or thatpest eventuallycontrol company. results O fromften, a guard bee will mosterroneously other groups called “killerof organisms, bee”) closely bees resemblesbee pollination,bounce off and your so headare manywithout bever- stinging. This is a areother most N orthabundant American in numbers honey bees; of botheven expertsages andwarning medicines that more made bees from and otherstings may follow. Do specieshave to and examine individuals them carefully in deserts to tell and them apart.fruits andnot swatseeds. at the bees. Walk calmly out of the area. savannahs,Africanized rather honey than bees inare lowland about 10 rain- to 15 percent If you are attacked by numerous Africanized bees forests.smaller The than region other aroundsubspecies Tucson, and races of Apis and are being stung, pull your shirt or blouse over Arizonamellifera. is Tthoughthey are tocalled host “Africanized” more kinds because your face to protect your eyes. Hold your breath ofthey bees are than the hybridanywhere progeny else resultingin the from the re- Africanizedif you can and get out Beeof the area.s Unfortunately, world,lease withof pure the A. possible m. scutellata exception (the African of honey somebee) desertsinto the in forests Israel. near In the São United Paulo, Brazil, in The infamous States,1956. T therehey arrived are about in southern 5000 speciesArizona offrom MexAfricanized- honey © bees.ico in On the a earlyglobal 1990s scale, and there quickly are established feralbee closely resembles Jeff Martin approximatelycolonies in rock 25,000 outcrops, named tree species, hollows, andother sa- North butguaro it is boots. likely Inthat cities, as manyAfricanized as 40,000 bees preferenAmerican- honey differenttially nest species under exist.sheds and in streetside concretebees—even experts have to water-meter boxes. examine them closely to tell them Africanized or not, a few foraging honey bees ECOLOGY apart. Africanized or not, a few Bees,are usually a highly no successfulcause for alarm. group T hederived only true danforaging- Africanizedhoney bees are bees usually may continueno cause forto follow and try to ger is encountering an Africanized colony and from wasps, live in almost all terrestrial alarm. Thesting only you true for dangerup to ¼is mileencountering (0.4 km). Do not jump provoking it. Stimuli that alert and engage the into a swimming pool or lake to escape them. Get habitats within our region. Except for an Africanized colony. In such cases stay clear defensive guard bees are ground vibration, rapid indoors as quickly as possible; an automobile is a the parasitic cuckoo bees, all female of the colony and contact a beekeeper or pest movement, dark clothing, and the carbon dioxcontrol- company.safe retreat. Don’t worry about bringing in a few beeside makein exhaled their breath. living Ifby a colonyforaging is aptin to be pro- bees with you; they will soon disperse and fly to- searchvoked, of stay protein-rich clear of it pollenand contact and sug- a beekeeper ward a lighted window. ary nectar from flowering plants. By moving pollen around from flower to Without the pollination services flower and plant to plant, bees perform bees provide, many plants would not vital and often unappreciated roles as produce seed-laden fruits from which punctathe most) and important the truly groupsocial, of bright pollinat- yellow andthe nextthat generation another of5,000 plants or wouldmore or so still remain blacking animals Sonoran on bumble earth. Yetbees bees (Bombus are not pennsylvagrow.- Withoutundescribed bees, and there unnamed would be by taxonomists. nicusout )to of “help” lower desert flowers; elevations. they collect few or no fleshy berries or fruits to pollen and nectar in order to feed sustainEco birds,logy mammals, and other Dthemselvesistributio andn their larvae. wildlife.Bees The are tunneling a highly activity successful of group that evolved ThereOf are the at approximatelyleast 45 genera 640 in 7flower- families, andbees aeratesfrom thewasps; soil theyand allowslive in water almost all terrestrial likelying plant 700 taxato 800 growing species in theof bees, Tucson distributedfrom infrequenthabitats withinrains to ourquickly region. Except for the withinMountains the Sonoran near the Desert Desert Region. Museum, We do penetratenot parasitic and reach cuckoo plant bees roots; (including and Ericrocis, Xe- knowapproximately the exact number80 percent because of these many bee genbees’- nitrogen-richromelecta, and feces Triepeolus fertilize spp.),the all female bees eraspecies are in have need flowers of taxonomic adapted forrevision, and numersoil.- Themake bees their themselves living by often foraging in search of pro- pollinated by bees. Similarly, at least provide food for lizards, mammals, ous new species are being described, and bee tein-rich pollen and sugary nectar from flow- 30 percent of our agricultural crops birds, insects, spiders, and other surveysrequire inbees many to movecounties pollen and between for Sonora, Mexarachnids.- ering plants. By moving pollen from flower to ico, are incomplete. The region around Tucson, flower and plant to plant, bees perform vital and Arizona, is thought to host more kinds of bees often underappreciated roles as the most im- than342 anywhere Bees else in the world, with the pos- portant group of pollinating animals on Earth. sible exception of some deserts in Israel. The Bees are an excellent example of the evolution- state of Arizona has 1300 native bee species. In ary fine-tuning of insect-plant symbioses: they the United States, there are about 3500 species are not out to “help” flowers; they simply collect of bees. On a global scale, there are approxi- pollen and nectar to feed themselves and their mately 20,000 named species, but it is likely larvae and, in the process, facilitate pollination.

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UC_ASDM-S2--TEXT_PT3.indd 311 9/9/15 2:18 PM Of the approximately 640 flowering plant Leafcutter bees (Megachile spp.) remove circu- taxa growing in the Tucson Mountains near lar pieces of leaves to fashion into cell walls. the Desert Museum, approximately 80 percent Resin bees (Heriades and some Megachile spp.) have flowers adapted for bee pollination. Simi- collect resins from creosotebush and brittle- larly, at least 80 percent of agricultural crops, bush to seal their linear nests in former beetle globally, require bees to move pollen between tunnels in dead tree branches. flowers. Many table foods—​like those in the broccoli family, as well as carrots, squashes, on- ions, melons, cucumbers, peppers, eggplants, tomatoes, avocados, coffee, and many fruits and nuts, to name just a few—​are pollinated by bees. But we depend on these “forgotten pol- linators” not only for about a third of our global food crops (many are wind-pollinated), but for other products as well. Cotton cloth is one even- tual product of bee pollination, as are many beverages and medicines made from fruits and seeds. leafcutter bee Without the pollination services bees pro- vide, many plants would not produce seed- Life History bearing fruits from which the next genera- Almost 80 percent of our native Sonoran Desert tion of plants would grow. Without bees, there bees excavate burrows in the ground for their would be few or no fleshy berries or fruits to brood cells. Cells can be placed a few inches (5 sustain birds, mammals, and other wildlife. cm) deep or 6 feet (2 m) or more in sandy soils. The tunneling activity (bioturbation) of bees Many species line their burrows or cells with helps aerate the soil and allows water to quickly waxy secretions produced from the Dufour’s penetrate and reach plant roots. Larval bees’ ni- glands within their abdomens. This lining wa- trogen-rich feces fertilize the soil. The bees are terproofs the cells, maintains humidity, and themselves food for lizards, mammals, birds, keeps organisms like fungi from destroying the insects, spiders, and other arachnids. food and the developing larvae. Most bees are In their daily foraging, bees harvest food- solitary and do not help one another. The life stuffs from flowers for themselves and their history for social bees, such as bumble bees, is larvae. Pollen is a rich source of amino acids, very different. proteins, fatty acids, vitamins, minerals, and Each female of the solitary kinds selects carbohydrates. Nectar provides sugars for the a site for her nest, excavates the tunnels, and energy boost that bees need to fly. Some des- forms and provisions the rounded cells with ert bees (such as Centris spp.) have specialized pollen and nectar. Usually the pollen balls are scrapers on their legs for harvesting oils from shaped by the female, and she lays a small white glands on the undersides of specialized flowers egg on the provision mass. She can make about (such as Krameria spp. and Janusia spp.). These one cell every day of her life. Most ground-nest- energy-rich oils are mixed with pollen as larval ing bees seal their brood cells with a spiral mud food and are also used to help construct brood closure. This behavior is called mass provision- cells. Other bees collect small pebbles, plant ing, since the mother bee collects and prepares hairs, or floral resins for use as building ma- at one time all the pollen and nectar food each terials. Some bees, such as mason bees in the developing larva will need to complete its life genus Osmia, also require water and mud, with cycle from larval stages to newly emerged adult. which they construct their adobe-like nests. Not all bee larvae spin a silken cocoon, but

312 Animals

UC_ASDM-S2--TEXT_PT3.indd 312 9/9/15 2:18 PM some do. After laying an egg in each cell, the pheromones that elicit feeding and grooming solitary female has no further contact with her behavior in her daughters. The queen lays all progeny. She dies and will never see her brood. the eggs within the colony. Sweat bee colonies Although solitary, many of our Sonoran Desert are usually small, consisting of a few dozen or bees routinely nest with other females in very at most a few hundred individuals. large aggregated nest sites. Among them is our Highly social bees in our region include the common cactus bee (Diadasia rinconis), which introduced European honey bee (Apis mellifera) pollinates prickly pear, cholla, and saguaro and the native black and yellow bumble bees cacti. During the spring cactus bloom there in the genus Bombus. Bumble bee colonies are may be thousands to hundreds of thousands of annual, established by an inseminated queen aggregated nests over an area the size of a ten- that emerges from her winter retreat in spring nis court. and finds a suitable mouse nest or other under- Other native desert bees don’t go to the ground cavity in which to nest. The queen is bother of excavating their own nests. Instead, larger than her daughters and lays all the eggs they seek the abandoned exit holes and tun- after she has produced an initial small brood nels of wood-boring beetles (usually bupres- of workers. Males and queens are produced late tids and cerambycids) in dead limbs or stand- in the season. They mate, the males die, and ing dead trees. These bees are known by their the inseminated queens spend the fall and win- common names of leafcutter (Chalicodoma and ter “hibernating” below ground until the next Megachile) and mason bees (Osmia). Once a spring. beetle burrow is located, these females bring In Sonora, Mexico (near Alamos), and far- back cut pieces of leaves, resins, and pebbles or ther south, extremely social bees called “sting- mud balls with which to fashion cells and their less bees” (Melipona and Trigona spp.) live in thick, protective capping plugs. colonies with many thousands of individuals. Most of our Sonoran Desert bees have a (Although these bees do not sting, they can single generation per year, the adults typically bite, and will, if their nest is disturbed.) These emerging with the spring or summer wild- queens are physogastric, with abdomens swol- flower blooms. Some species, however, have len full of eggs. They are not able to fly once two or three generations per year. In a typical they begin laying eggs, and they will never life history, adult males and females mate soon leave the colony again. Thus, these social bees after emergence from their brood cells. Females represent a still greater caste differentiation construct and provision nests and lay eggs, and between queens and workers. Stingless bees the larvae develop rapidly underground. Dur- store as much as several quarts (liters) of honey ing cooler months the larvae usually stay in a in waxen storage pots that look like clusters of resting condition, or diapause, at either the pre- grapes. Indigenous peoples, including the Ma- pupal or the pharate adult stage (the pupal stage yans of the Yucatán Peninsula, find these nests just prior to the final molt and emergence as an in hollow trees and transport the log hives back active adult) until the following spring or sum- to their villages, where they tend the bees and mer, when they complete their metamorphoses periodically harvest their honey and beeswax. and emerge as adults. We can explore bee diversity by examining where bees live and which flowering plants they Social Behavior visit to collect food (pollen and nectar) and nest- A relatively small number of our desert bees ing materials (leaves, resins). are truly social. In the case of some sweat bees (Halictidae), a queen looks like other females in leafcutter and mason bees the colony, although she differs in having highly Leafcutter bees and mason bees (the common developed ovaries. She may or may not secrete names for many genera of bees in the family

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UC_ASDM-S2--TEXT_PT3.indd 313 9/9/15 2:18 PM Megachilidae) make up about 10 percent of our carpenter bees 1300 native Arizona bees species. Both groups Exceeded in size only by queen bumble bees, of bees typically nest in abandoned tunnels in these large, mostly black bees have massive dead trees and limbs left by emerging beetles, mandibles and excavate tunnels dime- to although a few are ground-nesting. Female leaf- nickel-sized in diameter in sound but dead cutter bees do not eat, but cut elliptical pieces wood. Our most common low-elevation carpen- from thin leaves, including those of rosebushes ter bee, Xylocopa californica arizonensis, nests in one- to two-year-old dead fruiting stalks of agave, sotol, and yucca. Females save some of the excavated sawdust from their linear gal- leries to form concave, spiral, “particleboard” cell partitions between their young. They lay a long egg on a pillow-like provision mass, and 309-352 116269 4/25/00 3:45the PM larva Page consumes 343 the entire mass before fi- nally defecating and becoming a pupa. The pupae wait in their cells until the next spring, although in some cases a generation matures faster and a second generation is produced in the same year. These bees cause little damage to structural timbers (although they will bur- green mason bee In their dailyrow quests into bees large harvest household nest,wood excavates structures). the tunnels, forms and foodstuffs from flowers for themselves provisions the rounded cells, and lays Females have short mouthparts and are often and their larvae. Pollen is a rich food an egg within each one. This behavior source of aminoseen acids, slitting proteins, the fattybases of isflowers, called “mass including provisioning,” since the and other garden plants. They carry these back acids, vitamins,those minerals, of Chilopsis and carbohy- and Tecomamother, to stealbee collects nectar and prepares at one to their tunnel nests to serve as adrates. protective Nectar provideswithout thepollinating energy these flowers.time all the The pollen larger and nectar food lining for their brood cells and helpboost maintain from sugarsXylocopa that bees varipuncta need to nestsfly. ineach dead developing logs of syca larva- will need to com- a constant humidity. Chemicals inSome the leavesdesert beesmore (Centris and) poplar,have special- along withplete chinaberry its life cycle trees from larval stages to help protect the eggs and developingized bee scrapers larvae onin their urban legs environments. for harvest- Its pupagolden and, males finally, estab through- complete from microbial attack. Leafcutter beesing areoils genfrom- glandslish leks on the(communal undersides matingmetamorphosis sites) on hilltops. into a newly emerged erally all black, often with faint whiteof stripes specialized on flowersThe males in the produce ratany rose-likeand adult. scents After that laying attract an egg in each cell, their abdomens. Species of the genusmalpighia Megachile families. females These for energy-rich mating. the solitary female has no further con- are the most common in our deserts,oils and are theyare mixed with pollen as larval tact with her progeny. Although solitary, can be found visiting mesquite andfood palo and verde are also used many of our Sonoran Desert trees. Females in the subgenus Chelostomoidesto help construct brood bees routinely nest with can be recognized by their massive cells.mandibles, Other bees collect other females in very large small pebbles, plant hairs, aggregated nest sites. Among with sharp cusps, which they use not only for or floral resins that they them is is our common cactus cutting leaves but also for collecting plant res- use as building materi- bee (Diadasia rinconis) which ins from brittlebush and creosotebush.als. Some The bees, such pollinates prickly pear, resins are used to top off their nestsas mason as a beesde- in the cholla, and saguaro terrent for marauding ants. In the Skygenus Islands, Osmia , also cacti. Its aggregations dur- shiny metallic green mason bees (e.g.,require Osmia water and ing the spring cactus bloom ribifloris, which pollinates manzanitamud flowers) with which to may number in the hun- nest in abandoned beetle burrows and,construct as their their dreds of thousands of Jeff Martin name suggests, use mud to constructadobe-like cell wall nests. © individual nests over an partitions. Leafcutter and mason beesLeafcutter gener bees- area the size of 2 to 3 ally have one or two generations per( yearMegachile in our) remove Carpenter bee tennis courts. carpenter bee area. circular pieces of Other native desert leaves to fashion into cell walls. bees don’t go to the bother of excavat- ing their own nests. Instead, they 314 Animals LIFE HISTORY actively search out the abandoned exit The vast majority of desert bees dig holes and tunnels of wood-boring burrows in the ground for their brood beetles (usually buprestids and ceram- cells. Cells can be just a few inches deep bycids) in dead limbs or standing dead or six feet or more down in sandy soils. trees. These bees are known by their UC_ASDM-S2--TEXT_PT3.indd 314 Many species line their burrows or cells common names of leafcutter9/9/15 2:18 (thePM with waxy secretions produced by genera Chalicodoma and Megachile) and glands within their abdomens. This mason bees (the genus Osmia). Once a lining waterproofs the cells, maintains beetle burrow is located, these females humidity, and keeps organisms like bring back cut pieces of leaves, resins fungi from destroying the food and the and pebbles or mud balls with which developing larvae. Most bees are solitary, to fashion cells and their thick, protec- that is each female selects a site for her tive capping plugs.

Bees 343 sweat bees Sweat bees (Halictidae) are some of our small- Honey Bee or Bumble Bee Stings est bees. These ground-nesting bees are black If you are stung by a honey bee or bumble bee, or bronze in color and visit a wide variety of remove the stinger immediately (with fingers flowering plants. Halictus and Dialictus are two or teeth, by scraping off with a fingernail, etc.) of our most common genera. Attracted by salts, to prevent more venom from being delivered. the tiny Dialictus species often land on the (Don’t take time to look for tweezers or other sweaty skin of hikers, drinking their perspi- instruments.) Be alert in the first several min- ration. (If you don’t notice them and flex your utes to an hour to any unusual symptoms that arm, you might be stung, but the stings are not may represent a life-threatening situation. Dif- ficulty breathing, dizziness, nausea, body rash, very painful.) Bright metallic green bees (Aga- or intense itching are warning signs of a po- postemon and Augochlorella spp.) are also com- tential systemic allergic reaction in your body mon desert bees. that, left untreated, could lead to anaphylactic shock and possible death. If you or someone you are with is stung and shows any of these symptoms, get yourself or them to an emer- gency room and medical treatment immedi- ately (but don’t drive recklessly). With ana- phylactic reactions, prompt action is crucial. If you know you are allergic, you may already be sweat bee carrying an Epipen auto injector (epinephrine) and know how to use it. It should only be used in an emergency based on some or all of the above warning symptoms. The vast majority of bumble bees people can easily withstand one or a few honey Arizona has far fewer native bumble bees than bee or other bee stings and only have minor California and states farther north into the discomfort. If, for example, you are stung on a finger or hand, you might experience pain Rocky Mountains. Our most common low- for the first few minutes and, over a period of elevation bumble bee, Bombus pennsylvanicus hours to days, intense itching, redness, and (formerly B. sonorus), is a large, brilliant black swelling (edema). You might even have swell- and yellow bee, with a broad black band across ing all the way up your arm. While uncomfort- a yellow thorax. It is often seen visiting thistle able, this swelling is not a life-threatening con- flowers. Bumble bees are truly social, with a dition. Most people see their doctor and just queen and a worker caste. They preferentially take some pain-killer and perhaps Benadryl nest underground in rodent burrows or mouse tablets for the itching. A simple home remedy for immediate sting pain is application of a nests. In urban areas, they often nest in aban- paste of moistened table salt. doned human articles, in upholstery, or under discarded boards or utility sheds. Colonies are found in the spring and are annual, living only until the first frosts of the fall.

digger bees are specialist pollinators of these gourd plants Bees known as digger bees are ground nest- (Cucurbitaceae). A large local bee, the gray ers, or kleptoparasites. Common genera are and black Centris pallida, is a common visitor the fast-flying, robust Anthophora and Centris. to palo verde flowers. Other members of the Squash and gourd bees (Peponapis and Xeno- genus Centris are specialists, harvesting floral glossa spp.) are commonly found nesting in oils (as brood food) from plants including Kra- pumpkin and gourd patches, and these bees meria and Janusia.

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UC_ASDM-S2--TEXT_PT3.indd 315 9/9/15 2:18 PM honey bees are large (about 1 in/20–​25 mm) social wasps Honey bees (Apis mellifera) are not native to the that build paper honeycomb-style nests. Paper Sonoran Desert but were purposely introduced wasps and other wasps in Arizona don’t pro- into the United States (from Europe) over 400 duce honey, but the honey wasp in Sonora years ago by the Plymouth colonists. These are (Brachygastra mellifica) does store some honey truly social bees, with large colonies of up to in the combs. Paper wasps are longer, thinner, 50,000 bees, headed by a single queen and smoother, and shinier than honey bees and with worker and drone castes. Honey bee colo- have longer, narrower waists (called petioles) nies are managed by beekeepers and are our than do bees. Common paper wasps include single most important pollinator of agricul- the yellow paper wasp (P. flavus), whose color tural crops. In the Sonoran Desert, since about is true to the name; the Navajo paper wasp (P. 1990, the Africanized race (hybrids of some comanchus navajoe), which is deep chocolate subspecies of European honeybees with the brown with the end of the abdomen yellowish; African honey bee Apis mellifera scutellata) has and the Arizona paper wasp (P. arizonensis), established large feral populations within cities which is slightly smaller and more spindle- and in rocky desert outcrops. Most of the honey shaped than the other two and is brownish-red bees you see on flowering plants are African- with thin yellow cross bands on the abdomen. ized honey bees. Some of the most impressive insects in the Sonoran Desert are the enormous taran- tula hawks (Pepsis spp.). These 1- to 1 ¾-inch Wasps (25–​45-mm) wasps sport brilliant gunmetal, blue-black bodies carried by fiery orange or jet Justin O. Schmidt black wings. The desert contains about a dozen Order: Hymenoptera species. Suborder: Apocrita Flightless female velvet “ants” (Dasymutilla spp.) are among the most colorful of all organ- Division: Aculeata isms in the desert. More than three dozen spe- Families: Pompilidae, Mutillidae, Crabronidae, cies live in the Sonoran Desert. They range in Sphecidae, Vespidae, Scoliidae size from tiny, ⅛-inch (4-mm) species to huge, Sonoran Desert genera: Pepsis, Dasymutilla, nearly 1-inch (25-mm) giants. Most are clothed Sphecius, Sceliphron, Polistes, Triscolia in red, orange, yellow, or silver coats of hair-like Spanish name: avispa setae (bristles) and look like moving fuzzy cot- Wasps comprise an enormous and diverse as- ton balls. Particularly large velvet ants include semblage of insects ranging from the smallest the black and red magnificent velvet ant D.( known insects—​tiny parasites of insect eggs—​ magnifica) and Satan’s velvet ant (D. satanus), to immense cicada killers and tarantula hawks. which is black with a yellowish-white furry ab- Most wasps are predators whose young feed on domen. The glorious velvet ant (D. gloriosa) is a other insects or arthropods, but a few groups long-haired, totally white velvet ant that looks have become vegetarians, similar to bees, and like a creosotebush seed on legs. collect pollen to feed to their larvae. Both sexes Cicada killers (Sphecius grandis) superfi- of wasps are typically strong fliers, but some cially resemble huge yellowjackets or hornets. species are flightless; in others, one sex, usually Yellow with tan patches, they are 1 to 1 ½ inches the male, is an excellent flier while the other (25–​40 mm) long. These powerful fliers have sex is flightless. large compound eyes. Perhaps the most conspicuous and com- Mud daubers (Sceliphron caementarium), monly seen wasps in the Sonoran Desert are sometimes called “dirt daubers” or “mud the paper wasps (Polistes spp.). Paper wasps wasps,” are thin, 1-inch-long (25-mm) black

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