Ashy Gray Lady Beetle

Olla v-nigrum

Classification

Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Order: Coleoptera
Suborder: Polyphaga
Superfamily: Coccinelloidea
Family: Coccinellidae
Subfamily: Coccinellinae
Genus: Olla
Species: v-nigrum

Pronunciation

How to pronounce Olla v-nigrum: /ˈɒl.la ˈviːˌnaɪ.ɡrəm/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Olla v-nigrum 153022806 by Sam Kieschnick. Used under a CC BY 4.0 license.

Olla v-nigrum 165435805 by Elizabeth Praetz. Used under a CC0 license.

Olla v-nigrum 249148487 by Sam Kieschnick. Used under a CC BY 4.0 license.

Olla v-nigrum 158435622 by Gene H. Used under a CC BY 4.0 license.

Olla v-nigrum 142147499 by Don Loarie. Used under a CC BY 4.0 license.

Olla v-nigrum 158311894 by Gene H. Used under a CC BY 4.0 license.

Summary

Olla v-nigrum, or Ashy Gray Lady Beetle, is a species within the Coccinellidae family that displays two striking color variants. It is predatory and plays a role in controlling pest populations, particularly aphids, although it faces competition from invasive species which affect its prominence in North America.

Physical Characteristics

Gray with black spots or black with two red spots; length of 3.7-6.1 mm; lateral margin of elytron feebly explanate; triangular shaped spots sloping away from where the wings meet.

Identification Tips

Confused with Chilocorus sp. which have more flared elytra and distinct shape; Olla v-nigrum has a white marking on its head unlike Chilocorus sp.

Habitat

Tree canopy and ground level; found in abundance during peak aphid abundance.

Distribution

Indigenous to Florida, throughout continental United States, to as far south as Argentina; also found in Hawaii, Guam, Asia, New Caledonia, and Reunion Island; recent records in the Canary Islands and Madeira.

Diet

Primarily preys on psyllids (especially immature stages) and various aphids; also feeds on eggs and larvae of Coleoptera and Lepidoptera.

Life Cycle

Egg stage lasts 1-2 days, larval duration averages 7 days, pupal phase lasts 4-5 days; total cycle from larva to adult is about 25 days; adults can live up to around 60 days; mean interval between generations is approximately 52 days.

Reproduction

Eggs are usually laid in masses with a viability of about 54.8%.

Predators

Parasitized by phorid wasps, particularly Phalacrotophhora quadrimaculata; also infected by fungi such as Hesperomyces virescens and Beauveria bassiana.

Ecosystem Role

Predators of aphids, contributing to aphid control; used in biological pest control in agriculture.

Economic Impact

Utilized for controlling pest populations in crops by preying on aphids and other pests; potentially impacted by competition with invasive species like Harmonia axyridis.

Similar Taxa

Misconceptions

Often confused with other lady beetle species due to similar appearances.