Brochymena diluta
Blatchley
Brochymena diluta is a of rough stink bug in the Pentatomidae, to North America. Originally described by Blatchley as a (Brochymena barberi diluta), it was reclassified as a full species within the Brochymena following a comprehensive taxonomic revision that split the former broader genus into two genera: Brochymena (20 species) and the newly erected Parabrochymena (10 species). As with other Brochymena species, it is cryptically colored and primarily arboreal.

Pronunciation
How to pronounce Brochymena diluta: /bɹoʊˈkɪmɪnə dɪˈluːtə/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Brochymena diluta can be distinguished from the brown marmorated stink bug (Halyomorpha halys) by examining two key characters: the lack white bands on the last two segments (present in H. halys), and the leading edge of the pronotum ( behind the ) bears fine teeth (absent in H. halys). The exhibits the typical Brochymena of gray coloration with black and white or ivory speckling, providing camouflage against lichen-mottled bark.
Images
Habitat
Arboreal; associated with trees and shrubs. overwinter beneath loose bark or in other sheltered outdoor locations, rarely entering structures.
Distribution
North America; specific range details for B. diluta not extracted from available sources, but the Brochymena is broadly distributed across the continent.
Seasonality
are active in spring and fall when emerging from and entering hibernation. They may be observed on warm, sunny winter days.
Life Cycle
are laid in small clusters on twigs of trees. Nymphs progress through four instars before reaching adulthood. Development from egg to is lengthy, resulting in a single annually in temperate climates.
Behavior
fly well and may alight on fences, sidewalks, or other contrasting surfaces where they become visible. They are known for their ability to withstand cold temperatures, with documented instances of surviving extended freezing. They aggregate beneath bark for winter shelter.
Ecological Role
Suspected to feed on sap of trees and shrubs; possibly occasionally predatory or scavenging on other insects. Serves as prey for various including the sand wasp Bicyrtes quadrifasciata, birds, fence lizards, and tachinid flies (Trichopoda spp.).
Human Relevance
Not a pest ; does not invade homes in large numbers like the brown marmorated stink bug. May occasionally enter structures with firewood but remains primarily outdoors. No economic importance.
Similar Taxa
- Halyomorpha halys (brown marmorated stink bug) pest easily confused with Brochymena ; distinguished by banded and lack of pronotal teeth
- Parabrochymena speciesFormerly classified within Brochymena; separated based on new morphological characters at the generic level
More Details
Taxonomic History
Originally described as Brochymena barberi diluta by Blatchley, later elevated to status as Brochymena diluta. The 1992 taxonomic revision by McPherson and Ahmad redefined Brochymena and erected Parabrochymena, with B. diluta remaining in Brochymena.
Cold Hardiness
Brochymena , including B. diluta, demonstrate remarkable cold . Specimens have been documented surviving a week or more in freezing conditions with subsequent recovery.
Sources and further reading
- BugGuide
- iNaturalist taxon
- A different stink bug on the move in the kitchen: four-humped stink bug, Brochymena quadripustulata — Bug of the Week
- Bug Eric: Rough Stink Bugs
- Bug Eric: Wasp Wednesday: Neorileya
- Bug Eric: Indoor Insects of Autumn (part 3 of 4)
- Bug Eric: October 2009
- Bug Eric: 2009
- DESCRIPTION OFPARABROCHYMENA, NEW GENUS, AND REDEFINITION AND REVIEW OFBROCHYMENAAMYOT AND AUDINET-SERVILLE (HEMIPTERA: PENTATOMIDAE), WITH CONSIDERATIONS ON NATURAL HISTORY, CHOROLOGICAL AFFINITIES, AND EVOLUTIONARY RELATIONSHIPS