Bruchine
Guides
Acanthoscelides macrophthalmus
leucaena bruchine beetle, leucaena seed beetle
Acanthoscelides macrophthalmus is a seed-feeding beetle in the subfamily Bruchinae, native to the Neotropics and now widely distributed through human-mediated dispersal. The species is a specialist seed predator of Leucaena species, particularly the invasive weed Leucaena leucocephala, and has been introduced as a biological control agent in multiple regions. Adults are small beetles that oviposit on or near host seeds; larvae develop endophagously within seeds, passing through four distinct instars before emerging by cutting a circular exit window.
Acanthoscelides quadridentatus
Acanthoscelides quadridentatus is a seed beetle (Bruchinae) native to the Americas with introduced populations in Australia and southern Asia. In its native Brazilian Cerrado range, it exhibits phenotypic plasticity with two distinct morphs: melanic individuals that are approximately 1.1-fold larger, and lighter, smaller individuals. The species is a specialist seed predator of Mimosa setosa, attacking both M. setosa var. paludosa and M. setosa var. setosa. Attacked seeds fail to germinate, making this beetle a significant mortality factor for its host plant.
Algarobius
Algarobius is a genus of seed beetles in the family Chrysomelidae, subfamily Bruchinae, comprising approximately six described species. The genus is notable for its association with leguminous plants, particularly Prosopis species (mesquites). Algarobius prosopis has been widely used as a biological control agent against invasive mesquite weeds in South Africa. These beetles are specialized seed-feeders whose larvae develop within seeds.
Bruchidius terrenus
Bruchidius terrenus is a seed beetle (Chrysomelidae: Bruchinae) first described by Sharp in 1886. The species has been recorded across parts of Europe (Bulgaria, France, Romania) and the conterminous United States, though its North American presence may represent introduction. Like other Bruchidius species, it is a seed-feeding beetle whose larvae develop inside legume seeds. The species has been treated under the genus Pygobruchidius in some classifications, reflecting ongoing taxonomic uncertainty in this group.
Bruchus affinis
seed beetle
Bruchus affinis is a univoltine seed beetle native to the western Palaearctic Region, first recorded in North America in Canada (British Columbia, Ontario, Québec) before 2007. It was likely introduced via imported Lathyrus seeds for planting. The species develops inside seeds of Lathyrus species, with adults feeding on pollen and nectar. Development from egg to adult requires approximately 60 days. The parasitoid Dinarmus basalis has been recorded causing about 10% mortality in Canadian populations.
Bruchus loti
Bruchus loti is a seed-feeding beetle in the family Chrysomelidae that primarily attacks seeds of Lathyrus japonicus, a legume species. Its larvae bore through hard seed coats to consume seed contents, a behavior that can enhance germination by breaking seed dormancy. However, heavy consumption by unparasitised larvae reduces seed survival. The species is subject to parasitism by at least two idiobiont parasitoid wasp species, Pteromalus sp. and Dinarmus sp., which indirectly benefit the plant by reducing larval feeding intensity and improving seed germination outcomes.
Megabruchidius
Megabruchidius is a genus of seed beetles in the subfamily Bruchinae (Chrysomelidae), established by Borowiec in 1984. The genus comprises Asian species that have become invasive in Europe, North America, South America, and South Africa. At least two species are well-documented: M. dorsalis and M. tonkineus, both specialized feeders on seeds of Gleditsia (honey locusts) and related Caesalpinioideae legumes. These beetles complete their entire larval development inside seeds, emerging as adults through exit holes. The genus has attracted significant research attention due to its economic impact as a pest of ornamental and forestry trees, its expanding host range in introduced regions, and its potential use as a biological control agent for invasive honey locust.
Megacerus
Large-horned Bruchids
Megacerus is a genus of seed beetles in the family Chrysomelidae, subfamily Bruchinae, commonly known as large-horned bruchids. The genus contains approximately nine described species in North America. Species in this genus are seed specialists, with larvae developing endophytically within seeds of host plants, primarily in the family Convolvulaceae. Adults are characterized by prominent genal or frontal horns, particularly in males. The genus has been studied for its potential use in biological control of weedy bindweeds.
Megacerus cubiculus
Cubical Bruchid
Megacerus cubiculus is a species of seed beetle in the subfamily Bruchinae, commonly known as the Cubical Bruchid. It occurs across Central and North America. Like other members of the genus Megacerus, it is associated with leguminous host plants. The species has been documented in 488 iNaturalist observations, indicating it is moderately well-recorded.
Megacerus discoidus (Say, 1824)
red megacerus
Megacerus discoidus is a seed-feeding bruchine beetle in the family Chrysomelidae. It is a specialist predator of hedge bindweed (Calystegia sepium) seeds, with larvae completing their entire development within individual seeds. The species has been studied for its potential use in biological control of this weedy vine. It occurs in North America and Central America.
Pachymerus nucleorum
Coconut Borer
Pachymerus nucleorum is a bruchine seed beetle that develops within palm seeds, primarily attacking species in the Arecaceae family. Larvae feed on endosperm inside hard-shelled fruits, with documented hosts including babassu palm (Attalea/Orbinya spp.), licuri palm (Syagrus coronata), and queen palm (Syagrus romanzoffiana). The species occurs in Brazilian biomes including Caatinga and Atlantic Forest remnants, where it functions as a primary seed predator. Adults are subject to parasitism by braconid wasps, particularly Heterospilus prosopodis. The species has been observed in both natural vegetation and managed habitats, with parasitism rates varying by habitat complexity.
Sennius
seed beetles, pea and bean weevils
Sennius is a New World genus of seed beetles (subfamily Bruchinae) within Chrysomelidae, containing at least 20 described species. Species are organized into multiple species groups, with the S. abbreviatus group being the largest and most thoroughly studied, comprising 14 species. The genus is characterized by distinctive male genitalia morphology, particularly patterns of sclerites and internal sac structure. Several species have been described from Mexico, Central America, and South America, with ongoing taxonomic revisions revealing new species and clarifying host plant relationships.
Stator limbatus
Stator limbatus is a leaf beetle in the family Chrysomelidae, native to the southwestern United States, Mexico, and northern South America. It has established populations in multiple regions outside its native range, including Hawaii, South Africa, the Middle East, and Mediterranean islands. The species occupies xeric and semi-arid environments and has been documented feeding on legume seeds.