Anasa tristis

Anasa tristis

''Anasa tristis'' of the family Coreidae is a major pest of squash and pumpkins, and is a vector of the cucurbit yellow vine disease bacterium. These bugs can emit an unpleasant odor when disturbed. It is commonly known as the squash bug but shares this name with certain other species.
Squash Bug Eggs - Anasa tristis Tiny, eggs that were laid in a cluster on the underside of a leaf in a rural garden.

Squash bugs cause severe damage to plants because they secrete highly toxic saliva into the plants. As a result, the foliage wilts, turns black, and dies following feeding. This malady is sometimes referred to as "anasa wilt", which can kill a plant. However, the amount of damage to a plant is directly proportional to the density of the squash bugs feeding on it. Additionally, squash bugs can vector a bacterium, Serratia marcescens, which causes Cucurbit Yellow Vine Disease. The insects transmit the pathogen and can harbor it within their bodies during the winter. Serratia marcescens is an interesting bacterium because it is opportunistic and different strains can colonize the tissues of both plants and animals. In insects, Serratia is not usually fatal, and squash bugs are not known to suffer any ill effects from infection. However, I once had an entire colony of mosquitoes succumb to a particularly acute infection of Serratia marcescens. The mosquitoes actually turned blood red from the ferocity of the infection. 

 Anasa tristis,Geotagged,Summer,United States,anasa,bug eggs,eggs,insect eggs,squash bug eggs

Appearance

The adult ''Anasa tristis'' is a greyish-brown, somewhat flattened insect reaching a length of about 1.5 cm and a width of 0.75 cm . There is often a row of alternate brown and gold spots along the margin of the abdomen. Adults survive for three or four months.
Squash Bug Nymphs First instar nymphs that had just hatched out of their eggs. They were hairy with light green abdomens, black heads, and black legs. They were about 3 mm long. The eggs were red and elliptical in shape, resembling tiny grape tomatoes. I spotted these nymphs on cucumber plants in an organic garden.

Squash bugs cause severe damage to plants because they secrete highly toxic saliva into the plants. As a result, the foliage wilts, turns black, and dies following feeding. This malady is sometimes referred to as "anasa wilt", which can kill a plant. However, the amount of damage to a plant is directly proportional to the density of the squash bugs feeding on it. Additionally ,squash bugs can vector a bacterium, Serratia marcescens, which causes Cucurbit Yellow Vine Disease. The insects transmit the pathogen and can harbor it within their bodies during the winter. Serratia marcescens is an interesting bacterium because it is opportunistic and different strains can colonize the tissues of both plants and animals. In insects, Serratia is not usually fatal, and squash bugs are not known to suffer any ill effects from infection. However, I once had an entire colony of mosquitoes succumb to a particularly acute infection of Serratia marcescens. The mosquitoes actually turned blood red from the ferocity of the infection.  Anasa tristis,Geotagged,Squash Bug,Squash Bug Nymphs,Summer,United States,bugs,nymphs

Behavior

In the southern part of its range, the adult female ''Anasa tristis'' lays two or three batches of about eighteen eggs, but in the northern part of the range it just lays a single batch. The eggs are oval, somewhat flattened and bronze in colour, and are deposited on the underside of the leaves of the host plant. They may be clustered close together or more widely dispersed but are often regularly arranged. The eggs hatch after seven to nine days into nymphs which have five instar stages. The first instar nymphs are hairy and green and about 2.5 mm in length. Each successive instar is darker in colour, larger and less hairy. The fifth instar is dark grey, with developing wing pads and about 10 mm in length. The complete nymphal stage lasts about 33 days.

References:

Some text fragments are auto parsed from Wikipedia.

Taxonomy
KingdomAnimalia
DivisionArthropoda
ClassInsecta
OrderHemiptera
FamilyCoreidae
GenusAnasa
SpeciesA. tristis