Category: Insects

Painted Lady Butterfly (Vanessa cardui)

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The Painted Lady Butterfly (Vanessa cardui) is one of the most widespread and fascinating species of butterfly, often called the “cosmopolitan” butterfly due to its exceptional global distribution.

Painted Lady Butterfly (Vanessa cardui)
Painted Lady Butterfly (Vanessa cardui)

Scientific Taxonomy

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Lepidoptera
  • Family: Nymphalidae (brush-footed butterflies)
  • Genus: Vanessa
  • Species: cardui (Linnaeus, 1758)

It belongs to the tribe Nymphalini within the subfamily Nymphalinae.

Description

The adult Painted Lady is a medium-sized butterfly with a wingspan of approximately 2–3.5 inches (5–9 cm), typically around 5.1–7.3 cm from wing tip to wing tip.

The upperside of the wings is predominantly orange-brown to pinkish-orange, with darker bases. The forewings feature a prominent black apical (tip) area adorned with prominent white spots and a white subapical bar along the leading edge. The hindwings display a submarginal row of five small black spots, sometimes with blue scales. The wing edges are distinctly scalloped.

The underside is more subdued and mottled with patterns of black, brown, gray, and some red-orange, featuring four small submarginal eyespots on the hindwing (a key distinguishing feature from similar species like the American Lady, Vanessa virginiensis, which has two larger eyespots).

Larvae (caterpillars) are grayish-brown with darker ends, a yellow dorsal stripe, and branched spines along the back and sides. Eggs are pale green with vertical ribs.

Behavior

Painted Ladies are highly migratory and fast-flying, capable of speeds up to 25–30 mph (40–50 km/h). They are strong, directional fliers that often use favorable winds.

Males defend territories against other males. In warmer climates, mating can occur year-round, though it ceases during colder periods. Adults are avid nectar feeders, visiting a wide variety of flowers (especially taller perennials), while larvae are polyphagous herbivores feeding on over 100 plant species, with favorites including thistles (Cirsium and Carduus), mallows, and other composites.

Their most remarkable behavior is long-distance migration, which is multi-generational (no single individual completes the full round trip). In North America, they overwinter in warmer southern regions (such as Mexico or the southwestern U.S. deserts) and move northward in spring, often triggered by rainfall and host plant availability, reaching as far as Canada and occasionally Alaska. In Europe and Africa, they undertake even longer journeys, including a documented 9,000-mile (≈14,500 km) round trip from tropical Africa to northern Europe (near the Arctic Circle) and back, spanning up to six generations. Southward return migrations often occur at high altitudes (over 500 meters), making them less visible. Migration appears driven primarily by environmental cues (e.g., weather, resource availability) rather than strict genetics.

Range

Vanessa cardui is the most widely distributed butterfly species in the world, found on every continent except Antarctica and Australia (though a related species, the Australian Painted Lady, V. kershawi, occurs there).

Its range spans:

  • North America (from subarctic Canada and southeastern Alaska south through the continental U.S. and Mexico)
  • Central America
  • Europe
  • Asia
  • Africa
  • Various oceanic islands

It inhabits diverse open habitats including fields, meadows, prairies, gardens, deserts, and disturbed areas, up to elevations of around 3,900 meters in some regions. Populations fluctuate dramatically with outbreaks occurring in some years due to favorable conditions for breeding and migration.

This adaptable, highly mobile species exemplifies resilience in the face of varying climates and habitats.

Sagebrush Checkerspot (Chlosyne acastus)

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The Sagebrush Checkerspot (Chlosyne acastus) is a medium-sized butterfly belonging to the brush-footed family, well-adapted to arid environments in western North America.

Sagebrush Checkerspot (Chlosyne acastus)
Sagebrush Checkerspot (Chlosyne acastus)

Scientific Taxonomy

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Lepidoptera
  • Family: Nymphalidae
  • Subfamily: Nymphalinae
  • Genus: Chlosyne
  • Species: Chlosyne acastus (W.H. Edwards, 1874)

Several subspecies are recognized, such as C. a. neumoegeni in parts of the southwestern range. The species is sometimes referred to as the Acastus Checkerspot in certain sources.

Description

The Sagebrush Checkerspot has a wingspan of approximately 1.5–2 inches (3.9–5.1 cm), with forewing lengths around 1.8–2.4 cm in some populations.

The upperside features a distinctive checkered pattern of black, orange-brown, and orange (paler in males, often brighter in females). The wings show black lines, smudges, and checks separating bands of pale to yellow-orange; the hindwing base may appear darker (sometimes largely black with limited orange in males). Postmedian bands can show red-orange tones in some individuals.

The underside is more contrasting, with the hindwing displaying bands of chalk-white (or pearly white spots) and brick red, outlined by black veins and edges. This ventral pattern, with more extensive white compared to similar species, aids identification.

It resembles other checkerspots (e.g., Northern Checkerspot or Rockslide Checkerspot) but is distinguished by habitat preference, lighter ventral banding, and specific wing markings.

(Images: Examples of Sagebrush Checkerspot upperside and underside views from various western U.S. locations.)

Behavior

Adults feed primarily on flower nectar from various plants in their arid habitats. Males perch in strategic locations (such as gulches or along washes) and sometimes actively patrol these areas to locate and court females. Flight is typically rapid and direct when disturbed, typical of many checkerspot species.

The flight period varies by region but generally occurs in spring to early summer (e.g., late April to late June in parts of the range like Oregon). Larvae feed on host plants in the Asteraceae family, including species such as green rabbitbrush (Chrysothamnus viscidiflorus), gray rabbitbrush (Ericameria nauseosa), desert yellow fleabane (Erigeron linearis), Mojave aster, and various asters in the genus Dieteria. The species is univoltine (one generation per year) in most areas, with adults timed to coincide with host plant and nectar availability.

Range and Habitat

The Sagebrush Checkerspot occurs across the western United States, from eastern North Dakota westward to eastern Washington, and southward to New Mexico, southern Arizona, and eastern California. It is found in states including Montana, Idaho, Oregon, Wyoming, Nevada, Utah, Colorado, and parts of the Great Basin and Southwest. Populations extend into shrub-steppe regions of southern British Columbia in some accounts, though primarily a U.S. species.

It inhabits dry, arid lowlands, typically below 5,000 feet in many areas (e.g., below 3,000 feet in parts of the Columbia and Snake River basins). Preferred habitats include sagebrush scrub, pinyon-juniper woodlands, dry gulches, washes, canyons, brushy flats, sage deserts, and hilly short-grass prairies. It thrives in shrub-steppe and semi-arid environments dominated by sagebrush and associated plants.

Overall conservation status is secure (G5 globally in many assessments), though local populations may face threats from habitat alteration in arid regions. It is not generally considered rare or imperiled across its broad range.

White-lined sphinx moth (Hyles lineata)

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The white-lined sphinx moth (Hyles lineata), also commonly known as the hummingbird moth or hawk moth due to its rapid, hovering flight and nectar-feeding behavior, is a member of the family Sphingidae. It is one of the most widespread and abundant sphinx moths in the Americas.

White-lined sphinx moth (Hyles lineata)
White-lined sphinx moth (Hyles lineata)

Description of the Adult

Adult white-lined sphinx moths are large and robust, with a wingspan of 2.5–3.5 inches (6–9 cm). The forewings are predominantly dark olive-brown to gray-brown, featuring a prominent broad pale tan or white band running diagonally from the base to the tip, along with narrower white streaks along the veins (the source of the “white-lined” name). The hindwings are darker, often blackish with a bright pink or rose central band and black spots. The thorax is “furry” and robust, the abdomen conical and extending beyond the wings at rest, and the proboscis is long for reaching deep into flowers. They are strong fliers, often mistaken for hummingbirds, and are primarily crepuscular (active at dawn and dusk) but can be diurnal in some conditions.

Life Cycle Stages

Like all Lepidoptera, H. lineata undergoes complete metamorphosis with four distinct stages: egg, larva (caterpillar), pupa, and adult.

  • Egg: Females lay small, spherical, pale green to yellowish eggs singly or in small groups on the leaves or stems of host plants. Each female can produce hundreds of eggs. Incubation typically lasts about 1 week, depending on temperature.
  • Larva (Caterpillar): The caterpillars are highly variable in color and pattern (polymorphic), ranging from bright yellow-green to dark green, black, or yellowish forms, often with complex markings including black, yellow, orange, or red spots, lines, or stripes along the body. All forms feature a prominent flexible horn (caudal horn) at the rear end, typical of sphingid larvae. They grow up to 3–3.5 inches (7–9 cm) long through five instars, feeding voraciously on foliage. This stage lasts about 3–4 weeks. In high-density years, caterpillars can form mass migrations across landscapes after defoliating host plants.
  • Pupa: Mature larvae burrow 1–4 inches into the soil to form a shallow chamber and pupate. The pupa is shiny dark brown to reddish-brown, spindle-shaped, about 1.5–2 inches long, with a prominent cremaster (hook-like structure) at the rear for anchoring. The pupal stage lasts 2–3 weeks in summer or longer if overwintering (in cooler regions, pupae may diapause through winter). Emergence is triggered by temperature and moisture cues.
  • Adult: Adults emerge from the pupa, live 1–2 weeks, and focus on reproduction and nectaring. They are important pollinators of tubular flowers.

The species typically completes 2 generations per year in most of its range, with multiple generations in warmer southern areas and potentially one in cooler northern zones. In some regions, it is migratory, with populations moving northward in spring and sometimes failing to overwinter in colder areas.

Host Plants and Ecology

Larvae are extremely polyphagous, feeding on a wide variety of plants across families such as Onagraceae (e.g., evening primrose Oenothera spp.), Portulacaceae (purslane), Vitaceae (grape), Rosaceae (apple, rose), and many others including willowherb, four o’clock, elm, tomato, fuchsia, and more. Adults nectar from long-tubed flowers like honeysuckle, columbine, larkspur, salvia, and evening primrose.

Geographic Range and Habitat

Hyles lineata has one of the broadest distributions among North American sphinx moths, ranging from Central America (including parts of South America in some records) through Mexico, the entire contiguous United States, and into southern Canada. It is occasionally reported in the West Indies, and vagrants have appeared in Eurasia and Africa. It prefers open habitats such as deserts, fields, gardens, prairies, woodlands edges, suburbs, and disturbed areas, thriving in diverse climates from arid to temperate. In areas like Nevada (including Las Vegas vicinity), it is common, especially during irruption years when populations boom due to abundant wildflowers or host plants.

This species plays a key ecological role as a pollinator and herbivore, with occasional outbreaks benefiting certain cultural groups historically (e.g., as a food source). It is not considered a major pest in most contexts, though larvae can defoliate garden plants during population spikes.

Desert Tarantula (Aphonopelma iodius)

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Aphonopelma iodius, commonly known as the Desert Tarantula (also called Great Basin blonde, Mojave Desert tarantula, northern blonde, or similar regional names in the pet trade), is a medium to large-bodied tarantula. Adults typically have a diagonal leg span of 3–5 inches (7.6–12.7 cm), with a body length (carapace to abdomen) of about 1.5–2.5 inches. Females are generally stockier and larger overall than males, while males have longer, more slender legs and a slimmer abdomen.

Desert Tarantula (Aphonopelma iodius)
Desert Tarantula (Aphonopelma iodius)

The coloration is usually dark brown to blackish or grayish-brown, with a covering of lighter (blondish, reddish-brown, or golden) hairs, giving it a somewhat “blonde” appearance in many individuals—especially noticeable on the carapace and legs. Like other New World tarantulas, it possesses urticating hairs on the abdomen, which it can kick off as a defensive mechanism to irritate predators’ skin, eyes, or respiratory system. The spider has small eyes clustered on a raised tubercle, powerful chelicerae (fangs), and a robust, hairy build typical of theraphosids. Its venom is mild and not medically significant to humans, causing pain similar to a bee sting at most.

Scientific Taxonomy

Kingdom:Animalia
Phylum:Arthropoda
Subphylum:Chelicerata
Class:Arachnida
Order:Araneae
Infraorder:Mygalomorphae
Family:Theraphosidae
Genus:Aphonopelma
Species:A. iodius

The taxonomy of the genus Aphonopelma has been complex and subject to multiple revisions due to morphological similarities among species. A major 2016 integrative taxonomic revision (using phylogenomic, morphological, and geospatial data) consolidated several previously described species or synonyms (such as A. brunnius, A. chamberlini, A. icenoglei in some contexts, A. melanium, A. nevadanum, A. zionis, among others) into A. iodius, resulting in a broader species concept. This species is now recognized as valid in current classifications, including the World Spider Catalog.

Behavior

A. iodius is a reclusive, nocturnal ambush predator that spends the majority of its life in a silk-lined burrow dug into the soil, often under rocks, logs, or in desert flats. The burrow entrance may have a webbed mat or silken collar. It emerges primarily at night to hunt, ambushing passing prey such as insects (crickets, beetles, grasshoppers), other arthropods, and occasionally small vertebrates like lizards.

This species is generally docile and avoids confrontation. When threatened, it may rear up to display its fangs, kick urticating hairs, or flee rather than bite. Bites are rare and not dangerous to humans. A notable behavioral trait is the seasonal activity of mature males: during late summer through fall (typically August–October, depending on region), males leave their burrows and wander openly during daylight or twilight hours in search of receptive females. This leads to frequent sightings of males crossing roads or open ground during this mating period. Females remain in or near their burrows. Lifespan varies significantly by sex—males live around 3–7 years (often dying shortly after mating), while females can live 15–20+ years or longer in captivity.

Range and Habitat

Aphonopelma iodius is native to the arid southwestern United States, primarily inhabiting desert and semi-arid environments. Its range includes:

  • Southern California (including parts of the Mojave Desert, Central Valley fringes, and areas as far north as the Bay Area and Diablo Range in some populations)
  • Nevada (especially the Mojave Desert region)
  • Western Arizona
  • Southwestern Utah

It is particularly common in the Mojave Desert west of the Colorado River, extending into parts of the Great Basin and adjacent arid zones. Habitats consist of dry, open areas with sandy or rocky soils suitable for burrowing, including desert scrub, grasslands, and rocky hillsides. It avoids extremely hot, low-elevation Sonoran Desert cores (where the related A. chalcodes, the Desert Blonde Tarantula, predominates). Populations are often localized but can be abundant in suitable microhabitats.

This species is well-adapted to desert conditions, remaining in burrows during extreme heat or cold to conserve moisture and avoid predators such as tarantula hawks (Pepsis wasps), birds, and mammals.