Southwestern-us
Guides
Sphinx dollii
Doll's Sphinx, Doll's Sphinx Moth
Sphinx dollii is a medium-sized sphinx moth (Sphingidae) native to arid regions of the southwestern United States. Adults have a wingspan of 45–63 mm and are active from June to August. The species is univoltine, with larvae feeding exclusively on Juniperus species.
Stenaspis verticalis insignis
Red-headed Beauty
Stenaspis verticalis insignis is a subspecies of longhorn beetle in the family Cerambycidae, tribe Trachyderini. It occurs in the southwestern United States and Mexico. The species was collected during a 2018 Arizona collecting trip in the Santa Rita Mountains, where specimens were found on Baccharis sarothroides (desert broom). The subspecies is characterized by its distinctive coloration, which includes a red head in adults.
Stictomyia
Stictomyia is a small genus of picture-winged flies (family Ulidiidae) containing two described species. The genus is notable for its highly unusual morphology and ecology, particularly in Stictomyia longicornis, which exhibits beetle-like appearance and strong association with cacti. These flies are among the more aberrant members of the Ulidiidae, departing significantly from the typical wing-patterned, active-flying form of most picture-winged flies.
Stictomyia longicornis
Stictomyia longicornis is a small picture-winged fly in the family Ulidiidae. Adults measure approximately 4 millimeters in length and are found almost exclusively on prickly-pear cacti in the southwestern United States. The species has been reared from rotting cactus pads, indicating larval development in decaying cactus tissue. Adults are morphologically unusual among flies, with short wings plastered to the back and a beetle-like or true bug-like appearance.
Sympistis lachrymosa
A small noctuid moth described in 2008 by James T. Troubridge. It is known from a restricted range in the southwestern United States and has a brief adult flight period in autumn. The species epithet "lachrymosa" (tearful) may allude to markings or coloration on the wings.
Syssphinx hubbardi
Hubbard's Silk Moth, Hubbard's Silkmoth
Syssphinx hubbardi is a medium-sized giant silk moth in the family Saturniidae, with a wingspan of 56–76 mm. Adults are predominantly gray with bright pink hindwings that are exposed when the moth is startled. The species occurs in the southwestern United States and Mexico, with one generation per year in most of its range, though Texas populations may produce multiple generations. Adults are active from June through September, with peak activity in July and August.
Tanaocerus
desert long-horned grasshoppers
Tanaocerus is a genus of desert-dwelling grasshoppers in the family Tanaoceridae, containing at least two described species: T. koebelei and T. rugosus. These insects are restricted to arid regions of the southwestern United States and northwestern Mexico. The genus is notable for its elongated antennae, a distinctive trait that separates it from most other grasshopper groups.
Tarache geminocula
Tarache geminocula is a moth of the family Noctuidae, subfamily Acontiinae. It was first described by Clifford D. Ferris and J. Donald Lafontaine in 2009. The species occurs in the southwestern United States and northern Mexico, with adults active during the late summer months. Males have forewings measuring 10–11 mm, while females are slightly larger at 10–12 mm.
Tetraopes discoideus
Tetraopes discoideus is a small milkweed longhorn beetle in the family Cerambycidae, described by John Lawrence LeConte in 1847. Adults measure 7–9 mm in length, making this species notably smaller than congeners. The species is associated with milkweed plants (Asclepias spp.) throughout its range in the southwestern United States and Mexico. Adults have been observed resting, feeding, and mating on milkweed stems and flowers. Larvae develop by feeding on milkweed roots, either tunneling directly into large taproots or living in surrounding soil when roots are small.
Thaumatopsis crenulatella
Thaumatopsis crenulatella is a small moth in the family Crambidae, first described by William D. Kearfott in 1908. The species is known from a limited geographic range in the southwestern United States. It belongs to the subfamily Crambinae, which includes many grass-associated moths. Published records remain sparse, with few documented observations.
Thrincopyge
jewel beetles
Thrincopyge is a genus of jewel beetles (family Buprestidae) in the subfamily Polycestinae. The genus contains three described species: T. alacris, T. ambiens, and T. marginata. Adults are known for their striking metallic coloration, typically combining blue or green with vivid yellow. Larvae develop within the dried flowering stalks of sotol plants (Dasylirion spp.), while adults conceal themselves at the base of the plants among the long, strap-like leaves. The genus occurs in the southwestern United States and northern Mexico.
Tipula schizomera
Tipula schizomera is a large crane fly in the family Tipulidae, described by Charles Paul Alexander in 1940. It is distributed across the southwestern United States and Mexico, representing one of the Nearctic species in this diverse genus. As with other Tipula species, it belongs to a group commonly known as crane flies or daddy longlegs, characterized by elongated bodies and extremely long legs.
Trachelas pacificus
Bull-headed sac spider
Trachelas pacificus is a species of true spider in the family Trachelidae, distributed across the southwestern United States and northwestern Mexico. It is commonly found in houses and adults are present year-round. The species is part of a genus known for sac-like retreats and active hunting behavior rather than web-building.
Trichocnemis spiculatus neomexicanus
New Mexican ponderous borer
Trichocnemis spiculatus neomexicanus is a subspecies of the ponderous borer, a large prionine longhorn beetle native to western North America. The larvae are among the largest of any North American cerambycid, developing in dead or dying coniferous wood—particularly ponderosa pine. Adults are nocturnal and attracted to lights. This subspecies was described by Casey in 1890 and occurs in the southwestern United States and Mexico. The species has gained notoriety as the inspiration for modern chainsaw design, after Joe Cox observed the larva's opposable mandibles in action.
Trimerotropis arizonensis
Colorado River blue-wing grasshopper
Trimerotropis arizonensis is a band-winged grasshopper described by Tinkham in 1947. It belongs to the genus Trimerotropis within the subfamily Oedipodinae, a group characterized by colorful hind wings. The species is known from the southwestern United States, particularly Arizona. Very little detailed biological information has been published for this species specifically.
Trimerotropis latifasciata
broad-banded grasshopper
Trimerotropis latifasciata, the broad-banded grasshopper, is a band-winged grasshopper in the family Acrididae. It occurs in the southwestern United States and Mexico, with documented records from Arizona, Texas, Utah, and northeastern Mexico. The species is notable for its cryptic coloration that blends with lichen-encrusted clay substrates, making it exceptionally difficult to detect.
Tristyla alboplagiata
Tristyla alboplagiata is the sole species in the monotypic moth genus Tristyla, family Noctuidae. The species was described by John Bernhardt Smith in 1893. It is restricted to the southwestern United States.
Tylosis jimenezii
Tylosis jimenezii is a species of longhorn beetle in the family Cerambycidae, first described by Dugès in 1879. It belongs to the tribe Trachyderini, a group of often large and strikingly colored cerambycids. The species is currently considered a synonym of Tylosis jimenezi, with records from both the United States and Mexico. Limited field observations suggest it may be associated with Malvaceae host plants in arid regions of the southwestern United States.
Usingeriessa brunnildalis
Usingeriessa brunnildalis is a small crambid moth described by Harrison Gray Dyar Jr. in 1906. It is known from California and Texas in the southwestern United States. The species has a distinctive wing pattern with dark brown forewings that are lighter in the median area and at the anal angle, contrasting with gray hindwings. The larval stage is aquatic, inhabiting rocks in streams where it feeds on algae.
Vanduzea nolina
Vanduzea nolina is a treehopper species in the family Membracidae, described by Ball in 1932. The genus Vanduzea is characterized by species that are obligately associated with specific host plants, with adults and nymphs typically found on stems and in leaf axils. This species is named after its host plant genus Nolina (beargrass), indicating a specialized plant-insect relationship. Like other members of the tribe Amastrini, V. nolina likely exhibits ant-tended behavior, where honeydew-producing nymphs are protected by ants in exchange for nutritional rewards.
Virbia marginata
Virbia marginata is a moth in the family Erebidae, subfamily Arctiinae. It was described by Herbert Druce in 1885. The species is considered a synonym of Virbia rubicundaria in some taxonomic treatments, though this status appears unresolved across sources. Records indicate presence in parts of North America and Central America.
Vitula pinei
Vitula pinei is a small snout moth in the family Pyralidae, first described by Carl Heinrich in 1956. It occurs in the southwestern United States, where its larvae feed on pine cones. The species is distinguished by its small size and pale, finely dusted wing coloration.
Xanthonia dentata
Xanthonia dentata is a small leaf beetle in the family Chrysomelidae, described by Staines and Weisman in 2002. The species is known from the southwestern United States, where it has been collected in association with oak trees. Adults measure 2.8–3.4 mm in length and display distinctive coloration useful for identification.
Xyloryctes thestalus
Western Rhinoceros Beetle
Xyloryctes thestalus is a species of rhinoceros beetle in the family Scarabaeidae, commonly known as the Western Rhinoceros Beetle. Males possess prominent horns on the head and pronotum, a characteristic feature of the Dynastinae subfamily. The species is nocturnal and strongly attracted to lights, often appearing in large numbers at ultraviolet and mercury vapor light setups. It occurs across the southwestern United States and Mexico, with two recognized subspecies: X. t. thestalus and X. t. borealis.
Zadiprion rohweri
Pinyon Pine Sawfly
Zadiprion rohweri, commonly known as the Pinyon Pine Sawfly, is a species of conifer-feeding sawfly in the family Diprionidae. It is associated with pinyon pine (Pinus edulis and related species) in the southwestern United States and Mexico. The species was described by Middleton in 1931 and is one of several Zadiprion species specialized on pine hosts. Sawflies in this genus are known for gregarious larval feeding that can cause noticeable defoliation.
Zopherus granicollis granicollis
Zopherus granicollis granicollis is a subspecies of ironclad beetle in the family Zopheridae, a group known for their exceptionally hard exoskeletons that make them notoriously difficult for entomologists to pin. The genus Zopherus includes species frequently encountered on tree trunks at night, particularly in pine and juniper woodlands of the southwestern United States. This subspecies has been recorded from Middle America and North America.