Nephus
Taxonomic placing: Insecta, Holometabola, Coleoptera, Coccinellidae.
Geographic distribution: A mostly Old World genus, some of whose species were widely distributed through
Morphology: The adults have convex bodies that are mostly black with brown spots. Nephus includens has a very large brown spot on each elytron, whereas N. nigricans is almost totally black but the elytra’s margins are brown.
Life history: The species of Nephus are predators of various scale insects and (more rarely) of aphids. The threshold of development of many is around 10°C and 500-600 day degrees are required to complete a generation. Fecundity of Nephus includens, feeding on mealybugs, came to 130-160 eggs/female at 25°C and longevity was 70 days, but preying on Icerya seychellarum fecundity was only 50 eggs/female. Nephus kreissli produced an average of 120 eggs/female and lived about 66 days at 25°C.
Economic importance: Species of Nephus are important biological control agents, capable of controlling various Homoptera, mostly Pseudococcidae, but also some Monophlebidae (formerly assigned to the family Margarodidae) and aphids. Several species of Nephus are in commerce.
East Mediterranean species
Nephus includens (Kirsch): This species occurs in Mediterranean countries, including Turkey. It preys on Pseudococcidae but also on species of Icerya (Monophlebidae) and on aphids. The parasitoid Homalotylus flaminius Dalman (Encyrtidae) attacks N. includens and may detract from its efficacy, as would co-occurrence with another and larger predator, Cryptolaemus montrouziei.
Nephus kreissli Fürsch and Uygun: This species, so far known only from Turkey, apparently prefers Pseudococcidae but occasionally also preys on Coccidae and members of the coccoid family Eriococcidae. Its immatures feed on host eggs within their ovisacs. Fourth instar and adult N. kreissli could feed on young mealybugs parasitised by Anagyrus pseudococci or by Leptomastix dactylopii, but not on elderly parasitised hosts which had become mummified.
. Nephus nigricans Weise: A south-European species that feeds on several Pseudococcidae and on the aphid Brachycaudus helichrysi in Turkey.
Nephus sinuatomaculatus Sahlberg: Recorded as a predator of mealybugs in Turkey.
References
Abdel-Salam, A.H., Ghanim, A.A. and Awadalla, H.S.S. 2010. Biological attributes and life table parameters of Nephus includens (Kirsch) (Coleoptera: Coccinellidae) as a natural enemy of margarodid mealy bugs in Egypt. Journal of Plant Protection and Pathology 1: 51-62.
Aslan, M.M. and Uygun, N. 2005. The aphidophagus coccinellid (Coleoptera: Coccinellidae) species in Kahramanmarafl, Turkey. Turkish Journal of Zoology 29: 1-8.
Bayoumy, M.H. and Michaud, J.P. 2012. Parasitism interacts with mutual interference to limit foraging efficiency in larvae of Nephus includens (Coleoptera: Coccinellidae). Biological Control 62: 120-126.
Canhilal, R., Uygun, N. and Carner, G.R. 2001. Effects of temperature on development and reproduction of a predatory beetle, Nephus includens Kirsh (Coleoptera: Coccinellidae). Journal of Agricultural and Urban Entomology 18: 117-125.
Gkounti, V.T., Savopoulou‐Soultani, M. and Milonas, P.G. 2015. Intra‐ and interspecific interactions between Nephus includens and Cryptolaemus montrouzieri. Journal of Applied Entomology 139: 647-653.
Kaydan, M.B., Atlihan, R., Uygun, N. and Şenal, D. 2012. Coccinellid (Coleoptera: Coccinellidae) species feeding on coccoids (Hemiptera: Coccoidea) in Van Lake Basin, Turkey. Türkiye Biyolojik Mücadele Derneği 1: 37-46.
Kontodimas, D.C., Milonas, P.G., Stathas, G.J., Economou, L.P. and Kavllieratos, N.G. 2007. Life table parameters of the pseudococcid predators Nephus includens and Nephus bisignatus (Coleoptera: Coccinelidae). European Journal of Entomology 104: 407–415.
Muştu, M. and Kilincer, N. 2012. Life table and some feeding features of Nephus kreissli fed on Planococcus ficus. Phytoparasitica 41: 203-211.
Muştu, M. and Kilincer, N. 2014. Intraguild predation of Planococcus ficus parasitoids Anagyrus pseudococci and Leptomastix dactylopii by Nephus kreissli. Biocontrol Science and Technology 24: 257-269.
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