On this page
How to identify it
- Adults are only about 1.3 to 1.5 mm long, with a black to blackish-brown head, whitish-yellow legs and yellow to light brown antennae.[1]
- The best field mark is a bright yellow spot on the back of the thorax (the scutellum).[1]
- Scales it has killed may look puffy or darker than healthy scales, and the adult wasp leaves through an exit hole it makes in the scale's back.[1][3]
Look-alikes
| Look-alike | How to tell them apart |
|---|---|
| Other scale parasites (Metaphycus, Encarsia and Aphytis wasps) | UC IPM lists Aphytis, Coccophagus, Encarsia and Metaphycus wasps among the most important scale parasites. In Georgia, a Metaphycus species, not this one, was the most common parasite of lecanium scales.[3][2] |
Where it lives
It is found on almost every continent and is one of the most common Coccophagus species in North and South America. In the United States it has been recorded in Florida, on green scale, and in the urban landscapes of Georgia, North Carolina, South Carolina and Virginia, and it has been released in California against black scale.[1][2]
Biology and life cycle
Before laying an egg, a female taps a scale with her antennae; the scale responds by giving off a droplet of honeydew, which she drinks. She lays pale, oval to teardrop-shaped eggs on the scale's back, averaging 5.6 eggs a day.[1]
Fertilized eggs become females and unfertilized eggs become males. Females usually develop inside scales, while males may develop on the outside of the same or related scales.[1]
The larva feeds inside the scale and pupates there, head toward the scale's rear. The prepupal and pupal stages last 11 to 15 days, and the pupa turns black in its last week.[1]
Females outnumber males and live longer, up to five weeks, though mated females lived about 13 days at 27 °C (81 °F).[1]
It parasitizes most soft scales, especially citricola, plum, calico, European fruit lecanium, green, brown, black and Caribbean black scales. In the Southeast it was the only parasite that emerged from lecanium scale nymphs, and it also attacks adult scales and lowers their egg production.[1][2]
Damage and signs
Health risk
The sources describe it only as a tiny parasite of soft scales; none mentions stings or any risk to people or pets.[1][3]
Control
Prevention
No control is needed. It is a beneficial insect that reduces soft scale populations, so leave it alone.[1]
Biological control
It isn't available for purchase, so conserve the wild population: control scale-tending ants, grow a variety of flowering plants for nectar and pollen, and keep dust down on small plants.[1][3]
Pesticides
Broad-spectrum insecticide sprays are one of the main obstacles to biological control of soft scales. Its populations can be kept up through moderate, careful use of selective insecticides.[1]
Common questions
- What are the tiny holes in the scales on my plant?
- Round exit holes usually mean an internal parasite such as Coccophagus lycimnia has already killed the scale and emerged. Check for these holes before spraying.[3][1]
- Can I buy Coccophagus lycimnia?
- No. It isn't sold commercially, so the best approach is to protect the wasps already present.[1]
- When are Coccophagus wasps active?
- In southeastern U.S. landscapes, most lecanium scale parasites, of which this species was the most common in three states, were active from late March to late August.[2]
Sources
- University of Florida IFAS Extension (EDIS Featured Creatures), “Coccophagus lycimnia (Walker) (Hymenoptera: Aphelinidae): parasitoid of soft scale pests (EENY-810, 2024).” journals.flvc.org/edis/article/view/134442 (accessed 2026-11-09)
- Oxford University Press for the Entomological Society of America (Journal of Economic Entomology), “Natural enemy communities and biological control of Parthenolecanium spp. (Hemiptera: Coccidae) in the southeastern United States (Robayo Camacho et al. 2018, Journal of Economic Entomology 111:1558-1568).” doi.org/10.1093/jee/toy102 (accessed 2026-11-09)
- University of California Statewide IPM Program, “Pest Notes: Scales (UC ANR Publication 7408).” ipm.ucanr.edu/home-and-landscape/scales/ (accessed 2026-11-09)
- iNaturalist, “Coccophagus lycimnia taxon page (order and family).” www.inaturalist.org/taxa/298823 (accessed 2026-11-09)