Formicococcus njalensis (Laing)



Common name

Cocoa mealybug

Field characters

No information available.

Validation characters

Cerarii with more than 3 conical setae; cerarii on abdomen without auxiliary setae; discoidal pores in conspicuous clusters in median areas of dorsal thorax; circulus present; oral-collar tubular ducts present on dorsum of abdomen and posterior thorax, in small numbers on anterior thorax and head; oral collars absent from venter of head and thorax; dorsal setae filamentous, elongate; multilocular disk pores on venter of segments V or VI-VIII; anal bar present; translucent pores on hind coxa and tibia.


Formicococcus njalensis is similar to F. robustus (Ezzat & McConnell) by having more than 3 conical setae in most cerarii including anal-lobe pair, cerarii on abdomen without auxiliary setae, circulus present. Formicococcus njalensis can be distinguished (characters of F. robustus given in parentheses) by having dorsal oral-collar tubular ducts (lacking), long dorsal setae (short), dorsal setae filamentous (stiff), multilocular pores absent near lateral margin of abdomen (usually present).

U.S. quarantine notes

This species was intercepted at U. S. ports-of-entry 10 times between 1995 and 2012, with specimens originating from the African countries of Ghana, Nigeria, Senegal and Sierra Leone. We also have examined specimens taken in quarantine from Ivory Coast (Theobroma); Nigeria (Theobroma); Sierra Leone (Treculia). ScaleNet lists hosts in 36 plant families. It is commonly collected on cocoa. Formicococcus njalensis occurs in the Afrotropical zoogeographic region only. Three species of Formicococcus besides F. njalensis, F. polysperes Williams and F. robustus (Ezzat & McConnell) have been taken at U. S. ports-of-entry including: F. acerneus Williams (India, on Mangifera); F. erythrinae Williams (India, on Mangifera); and F. mangiferacola Williams (India, on mango).

Important references

EzzatMc1956; BalachFe1966; LePell1968.

Scalenet catalog and citation list

Click here for a Catalog.

  Formicococcus njalensis  
 Illustration by Ezzat & McConnell

Formicococcus njalensis

Illustration by Ezzat & McConnell

  Formicococcus njalensis

Formicococcus njalensis