Pharoscymnus numidicus Pic

Systematic position: Insecta, Holometabola, Coleoptera, Coccinelidae.

Geographic distribution: North Africa and the Middle East.

Morphology: The adult body is about 1.7 mm long, elongate and somewhat convex, elytra light brown (sometimes with 2 light spots that may merge), head slightly darker, partially covered by the pronotum. The larvae are red-black.

Life history: Both larvae and adults prey mostly on armored scale insects, sometimes also on Asterolecaniidae the year around, except during cold spells. The threshold of development is around 16ºC, and about 400 day degrees are required to complete a generation. The beetle raises 3-4 annual generations in the Middle East and there is considerable overlap of generations. A female lays about 400 eggs.

Economic importance: Pharoscymnus numidicus is a major predator of Parlatoria blanchardi, being more active during the spring months. It may devour >15 scales/day, prefers male prey, and the date cultivar affects number of prey taken. In Sudan the predator is an important enemy of Palmaspis phoenicis (Asterolecaniidae).

Natural enemy: The beetle is sometimes parasitized by the encyrtid Homalotylus flaminius Dalman.

References

Kehat, M. 1966. Lady-birds (Coleoptera, Coccinellidae) as Predators of Date Ppalm Pests in Israel. Ph.D., Hebrew University of Jerusalem.

Kehat, M. 1967. Studies on the biology and ecology of Pharoscymnus numidicus Pic (Coccinellidae), an important predator of the date palm scale Parlatoria blanchardi Targ. Annales de la Société entomologique de France 3: 1055-1067.

Kehat, M. 1968. The feeding behavior of Pharoscymnus numidicus (Coccinellidae), predator of the date palm scale, Parlatoria blanchardi. Entomologia experimentalis e applicate 11: 30-42.

Malki, F. 2015. Influence de quelques facteurs biotiques sur l’alimentation de deux espèces de coccinelles Pharoscymnus ovoïdeus et Pharoscymnus numidicus mise en cochenille blanche Parlatoria blanchardi Targ. M.Sc. thesis, Universite Kasdi Merbah, Ouargla, Algeria, pp.68 +annex.

Yousof, D.E., Mahmoud, M.E.E. and Mohamed, A.H. 2013. Prospects of biological control of date palm green pit scale Insect Asterolecanium phoenicis Rao (Homoptera: Asterolecaniidae) in Sudan. Persian Gulf Crop Protection 2: 42-48.