Eriopis connexa

Eriopis connexa has an oblong body shape. The base color is dark brown to black with yellowish relatively large, separated dots. The pronotum and the elytra (wing covers) have a yellowish margin. Each elytron has three separated dots and the enlargements of the margin, the pronotum two smaller dots and two enlargements of the margin. There are not always visible indications of sexual dimorphism in this beetle species, but at certain times in adulthood, females will have extended abdomens for egg production. Additionally, adult females can be distinguished from adult males by their significantly heavier weight.

Eriopis connexa is a neotropical species native to South America, but has been introduced to the United States for biological pest management. They may be found in Argentina (Buenos Aires, Catamarca, Córdoba, Chaco, Chubut, Entre Ríos, Formosa, La Rioja, Mendoza, Misiones, Neuquén, Río Negro, Salta, San Juan, Santa Fe, Santiago del Estero, Tucumán), Bolivia (Cochabamba, La Paz, Oruro), Brazil (Mato Grosso, Minas Gerais, Paraná, Pernambuco, Rio Grande do Sul, Santa Catarina, São Paulo), Ecuador (Guayas), Paraguay (Alto Paraná, Caazapá, Central, Kanindeyu, Paraguarí, Pte. Hayes, San Pedro), Peru (Apurimac, Arequipa, Ayacucho, Cusco, Lima), Uruguay (Florida, Maldonado, Montevideo, San José), and Venezuela.

There are five main sequential stages of development in Eriopis connexa: egg, larva, pre-pupa, pupa, and adult. The larval stage can be further broken into four instars. Laboratory studies indicate that individuals spend approximately two days in each of the first three instar stages, nearly four days in the fourth instar stage, one day in the pre-pupa stage, three to four days in the pupa stage, and the rest of their lives in the adult stage. However, duration of each stage can change based on prey offered to Eriopis connexa. Individuals usually live for around 60 days in total. Both males and females reach full sexual maturity on the fifth day of the adult stage. Individuals of both sexes are sexually receptive on the third day but are not yet at their maximum fertility and fecundity. This may be due to incomplete maturation of sexual organs.

Because Eriopis connexa is a voracious predator of aphids, a very destructive agricultural pest, and naturally occurs in crops of high economic importance, this predatory beetle species has been used frequently for biological control of pests. It was first introduced to the United States in order to control Russian wheat aphid (Diuraphasis norxia) populations. As insecticide resistance continues to evolve in many agricultural pests, alternative pest control methods have become more desirable and necessary. There is evidence that in South America, Eriopis connexa has potential as a natural predator of corn and sorghum pests.

In many Coccinella species, egg viability is negatively correlated with paternal sexual activity, but this trend is not present in Eriopis connexa, suggesting males in this species have adapted to more frequent matings. There is, however, a negative correlation between oviposition time and paternal sexual activity in E. connexa, suggesting that allomones in male seminal fluid stimulate faster onset of oviposition in females and virgin males have greater quantities of allomones present in their seminal fluid. Allomonal effects in seminal fluid proteins can also create subtle paternal effects, such as increased offspring size or development time, but paternal effects are not present in E. connexa, suggesting males and females of this species have similar interests in progeny phenotypes.