Acroclisoides

Members of Acroclisoides can be distinguished from other pteromalid genera by features detailed in taxonomic revisions, though specific diagnostic characters require examination of minute morphological structures typical of chalcid wasps. Acroclisoides sinicus has been synonymized with A. solus based on morphological and molecular analysis. Accurate identification to species level requires specialist taxonomic expertise and reference to the 2024 revision of the genus.

Associated with habitats where pentatomid stink bugs occur, including cultivated agricultural areas and semi-natural vegetation. Field records include association with sassafras (Sassafras albidum) and other host plants of pentatomid bugs. Laboratory colonies have been maintained at 25-26°C, 60-70% relative humidity, and 16:8 light:dark photoperiod.

Oriental region (type locality for A. sinicus: China, described 1988); Afrotropical region; Australian region (New South Wales, Queensland, South Australia); Holarctic region including Europe (northern Italy, Switzerland) and North America (USA: Alabama, Georgia, Maryland; Canada). The distribution of A. sinicus has expanded significantly in recent decades, with adventive populations established in Europe and North America.

Obligate hyperparasitoid feeding on the pupal stage of scelionid primary parasitoids (family Scelionidae) developing within pentatomid eggs. Does not parasitize eupelmid primary parasitoids or unparasitized host eggs under tested conditions. Adult food source includes honey.

• Trissolcus japonicus - hyperparasitoid host (primary parasitoid)Scelionidae; low exploitation rate (4.0%) in laboratory tests
• Trissolcus mitsukurii - hyperparasitoid host (primary parasitoid)Scelionidae; strongly preferred host with 96.2% exploitation rate
• Trissolcus basalis - hyperparasitoid host (primary parasitoid)Scelionidae; parasitoid of Nezara viridula
• Trissolcus euschisti - hyperparasitoid host (primary parasitoid)Scelionidae
• Trissolcus edessae - hyperparasitoid host (primary parasitoid)Scelionidae
• Telenomus podisi - hyperparasitoid host (primary parasitoid)Scelionidae
• Halyomorpha halys - indirect hostPentatomidae; egg masses serve as habitat for primary parasitoid hosts
• Nezara viridula - indirect hostPentatomidae; green vegetable bug
• Chinavia hilaris - indirect hostPentatomidae; North American records
• Euschistus sp. - indirect hostPentatomidae; North American records
• Brochymena sp. - indirect hostPentatomidae; North American records
• Plautia stali - indirect hostPentatomidae; Asian records
• Erthesina fullo - indirect hostPentatomidae; Asian records
• Palomena prasina - indirect hostPentatomidae; European records
• Arma custos - indirect hostPentatomidae; European records

Development occurs entirely within pentatomid eggs that contain primary parasitoid hosts. The hyperparasitoid exploits only the pupal stage of scelionid primary parasitoids, not egg, larval, or pharate adult stages. Meconium expulsion by the primary parasitoid around day 5 signals the transition to pupal stage, which serves as the cue for parasitization. Pharate adults of primary parasitoids are recognizable at 7-9 days. Multiple generations can be reared in laboratory conditions.

Extremely selective host recognition behavior targeting only pupal-stage scelionids. Shows strong olfactory attraction to volatiles emitted by egg masses parasitized by preferred hosts (Trissolcus mitsukurii), with no response to egg masses parasitized by non-preferred hosts (T. japonicus) or unparasitized eggs. Exhibits intraspecific aggression in confined conditions, with females killing conspecific females. Females demonstrate clear probing and oviposition preferences in two-choice tests.

Secondary parasitoid (hyperparasitoid) occupying the highest trophic level in multitrophic systems involving pentatomid pests and their parasitoid guilds. As an obligate hyperparasitoid of scelionid biological control agents, it may reduce the effectiveness of primary parasitoids used for management of invasive stink bugs. The species could alter parasitoid community composition in areas where multiple Trissolcus species coexist, potentially favoring T. japonicus over T. mitsukurii through differential exploitation.

Emerging concern for biological control programs targeting Halyomorpha halys (brown marmorated stink bug) and other invasive pentatomids. Laboratory studies indicate A. sinicus could limit population development of Trissolcus mitsukurii while having minimal effects on T. japonicus, potentially influencing which primary parasitoid species are selected for augmentative biological control. The genus represents a new component in adventive food webs in Europe and North America that may complicate pest management strategies.

• AnastatusBoth are pteromalid parasitoids associated with pentatomid eggs, but Acroclisoides is an obligate hyperparasitoid of scelionids while Anastatus species are primary parasitoids; Acroclisoides does not successfully parasitize eupelmid hosts including Anastatus under tested conditions.
• Other Pteromalidae genera in MetasteninaeAcroclisoides can be distinguished by its specific association with scelionid hyperparasitism and morphological features detailed in the 2024 revision of the genus.

• hyperparasitoid
• biological control
• invasive species
• pentatomidae
• scelionidae
• pteromalidae
• hymenoptera

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Reproductive and Developmental Biology of Acroclisoides sinicus, a Hyperparasitoid of Scelionid Parasitoids
• Hyperparasitism of Acroclisoides sinicus (Huang and Liao) (Hymenoptera: Pteromalidae) on Two Biological Control Agents of Halyomorpha halys
• Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae)
• TWO SPECIES OF ACROCLISOIDES GIRAULT AND DODD (HYMENOPTERA: PTEROMALIDAE) PARASITIC ON TRISSOLCUS BASALIS (WOLLASTON) (HYMENOPTERA: SCELIONIDAE), A PARASITOID OF NEZARA VIRIDULA (L.) (HEMIPTERA: PENTATOMIDAE)
• Figure 3 from: Sabbatini Peverieri G, Mitroiu M-D, Bon M-C, Balusu R, Benvenuto L, Bernardinelli I, Fadamiro H, Falagiarda M, Fusu L, Grove E, Haye T, Hoelmer K, Lemke E, Malossini G, Marianelli L, Moore MR, Pozzebon A, Roversi P-F, Scaccini D, Shrewsbury P, Tillman G, Tirello P, Waterworth R, Talamas EJ (2019) Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae). Journal of Hymenoptera Research 74: 13-155. https://doi.org/10.3897/jhr.74.46701
• Figure 5 from: Sabbatini Peverieri G, Mitroiu M-D, Bon M-C, Balusu R, Benvenuto L, Bernardinelli I, Fadamiro H, Falagiarda M, Fusu L, Grove E, Haye T, Hoelmer K, Lemke E, Malossini G, Marianelli L, Moore MR, Pozzebon A, Roversi P-F, Scaccini D, Shrewsbury P, Tillman G, Tirello P, Waterworth R, Talamas EJ (2019) Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae). Journal of Hymenoptera Research 74: 13-155. https://doi.org/10.3897/jhr.74.46701
• Figure 2 from: Sabbatini Peverieri G, Mitroiu M-D, Bon M-C, Balusu R, Benvenuto L, Bernardinelli I, Fadamiro H, Falagiarda M, Fusu L, Grove E, Haye T, Hoelmer K, Lemke E, Malossini G, Marianelli L, Moore MR, Pozzebon A, Roversi P-F, Scaccini D, Shrewsbury P, Tillman G, Tirello P, Waterworth R, Talamas EJ (2019) Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae). Journal of Hymenoptera Research 74: 13-155. https://doi.org/10.3897/jhr.74.46701
• Figure 1 from: Sabbatini Peverieri G, Mitroiu M-D, Bon M-C, Balusu R, Benvenuto L, Bernardinelli I, Fadamiro H, Falagiarda M, Fusu L, Grove E, Haye T, Hoelmer K, Lemke E, Malossini G, Marianelli L, Moore MR, Pozzebon A, Roversi P-F, Scaccini D, Shrewsbury P, Tillman G, Tirello P, Waterworth R, Talamas EJ (2019) Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae). Journal of Hymenoptera Research 74: 13-155. https://doi.org/10.3897/jhr.74.46701
• Figure 4 from: Sabbatini Peverieri G, Mitroiu M-D, Bon M-C, Balusu R, Benvenuto L, Bernardinelli I, Fadamiro H, Falagiarda M, Fusu L, Grove E, Haye T, Hoelmer K, Lemke E, Malossini G, Marianelli L, Moore MR, Pozzebon A, Roversi P-F, Scaccini D, Shrewsbury P, Tillman G, Tirello P, Waterworth R, Talamas EJ (2019) Surveys of stink bug egg parasitism in Asia, Europe and North America, morphological taxonomy, and molecular analysis reveal the Holarctic distribution of Acroclisoides sinicus (Huang & Liao) (Hymenoptera, Pteromalidae). Journal of Hymenoptera Research 74: 13-155. https://doi.org/10.3897/jhr.74.46701
• Revision of Acroclisoides Girault & Dodd, 1915 (Chalcidoidea, Pteromalidae, Metasteninae).