Umbonia
Burmeister, 1835
Thorn Treehoppers
Species Guides
1- Umbonia crassicornis(Thorn bug)
Umbonia is a of treehoppers in the Membracidae, characterized by pronounced pronotal modifications that form thorn-like or horn-like projections. The genus occurs primarily in the Neotropics, with distributed from the southern United States through Central America to South America. Members of this genus exhibit subsocial , with females providing extended parental care to nymphal offspring. Several species, particularly Umbonia crassicornis, have been studied intensively for their complex maternal care systems involving between mothers and offspring. The genus includes approximately 16 described species, with Umbonia crassicornis being the most commonly encountered and economically significant species.



Pronunciation
How to pronounce Umbonia: //ʌmˈboʊniə//
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Identification
in the Umbonia are distinguished from other membracid genera by their elongated, pointed pronotal processes that project posteriorly or dorsally, often resembling plant thorns. The pronotum is greatly expanded and modified, extending backward over the and wings. is pronounced in several species, with females typically bearing longer and more robust pronotal spines than males. The body is relatively large for membracids, with reaching 11–13 mm in length. Species-level identification requires examination of pronotal shape, spine length and curvature, and coloration patterns.
Images
Habitat
Tropical and subtropical forest environments, including secondary growth and urban ornamental plantings. occupy a range of plants, primarily woody trees and shrubs.
Distribution
Central America, South America, and southern Florida (United States). The reaches its northern distributional limit in Florida, where freezing temperatures limit range expansion.
Diet
Phloem-feeding on plant sap; specific host plant associations include leguminous trees, particularly Pithecellobium dulce.
Host Associations
- Pithecellobium dulce - primary favorite for Umbonia crassicornis in Puerto Rico and Florida
- Leguminosae - primarily attacks leguminous trees
Life Cycle
Females deposit a single mass and remain with the eggs. Prior to hatching, females create spiral bark slits with the ovipositor; first instar nymphs aggregate along these slits. Females guard nymphs until they reach adulthood, using front to retrieve wandering nymphs. Nymphal development occurs in ; aggregations fragment upon sexual maturity.
Behavior
Highly subsocial with extended maternal care. Nymphs produce substrate-borne vibrational signals in synchronized bursts that elicit maternal antipredator . Mothers respond to offspring signals with defensive behaviors including body rocking and alarm signaling. Females produce simple pulse-type vibrational alarm signals when disturbed, causing nymphs to move to sheltered positions on the underside of leaves. Males exhibit mate guarding behavior, remaining with females after copulation to prevent rival mating. Mating occurs at natal sites with sibling mating common in some .
Ecological Role
Human Relevance
Umbonia crassicornis is considered a pest of ornamental trees in Puerto Rico and Florida, causing twig and branch damage and reducing aesthetic value through honeydew secretion and associated . The female's pronotal spine can cause injury to barefoot individuals. Controlled using including diazinon, sevin, malathion, and endosulfan.
Similar Taxa
- other Membracidae generaUmbonia is distinguished by its elongated posteriorly-projecting pronotal spine and pronounced in spine length; other may have different pronotal modifications (e.g., globular, foliaceous, or -mimicking forms) or lack the distinctive thorn-like projection
- Cyphoniaboth have elaborate pronotal modifications, but Cyphonia typically exhibits -mimicking forms with paired globular processes rather than single spines
- Heteronotusalso -mimicking with bizarre pronotal shapes, but lacks the characteristic elongated thorn-like projection of Umbonia
Sources and further reading
- BugGuide
- Wikipedia
- GBIF taxonomy match
- iNaturalist taxon
- NCBI Taxonomy
- Catalogue of Life
- Bizarre, beautiful extremes | Beetles In The Bush
- Alarm Behavior of Brooding Female Umbonia crassicornis (Homoptera: Membracidae)
- Reproductive Behavior and Dispersal in Umbonia crassicornis (Homoptera: Membracidae)
- AGGREGATING BEHAVIOR OF UMBONIA CRASSICORNIS (HOMOPTERA: MEMBRACIDAE)
- OFFSPRING-PARENT COMMUNICATION IN A SUBSOCIAL TREEHOPPER (HEMIPTERA: MEMBRACIDAE: UMBONIA CRASSICORNIS)
- Age effects on reproductive behavior in the treehopper umbonia crassiscornis (Hemipera : membracidae)
- Umbonia crassicornis (Amyot & Serville, 1843) (Hemiptera: Membracidae) nymphal aggregation size and density affect host plant and treehopper growth
- Female‐biased Sex Ratios in the Neotropical TreehopperUmbonia ataliba(Homoptera: Membracidae)
- Influence of Freezing Temperatures on the Distribution ofUmbonia crassicornis(Hemiptera: Membracidae) in Florida
- Colonization and Abandonment of Host Trees in a Natural Setting on Key Largo, Florida by the Treehopper, Umbonia crassicornis (Amyot and Serville) (Hemiptera: Membracidae)
- Notes on the Accidental Introduction of Umbonia crassicornis (Amyot and Serville)— (Hemiptera: Membracidae) into Puerto Rico and its Control