Belongs within: Coccophaginae.
Coccophagus is a cosmopolitan genus of small wasps including parasitoids of scale insects. It is distinguished from many related genera by its relatively setose thorax (Hayat 1983).
Devour scale or devour my sister?
Published 7 October 2024
Over the decades, many researchers have focused their attention on parasitoid wasps, hoping that their appetites may be deployed in the biological control of economic pests. Among the major pests of commercial crops are the sedentary suckers known as scales. And among the parasitoids that attack scales are the many species of the genus Coccophagus.
Coccophagus is a genus of chalcidoid wasps of the family Aphelinidae, found anywhere in the world that contains their scale hosts. Around two hundred species of Coccophagus have been described to date, with new ones being added continuously. All are small wasps, little more than a millimetre in length. Not surprisingly for such a large genus, defining features have been something of a challenge to identify, but noteworthy characters include a moderately hairy body with relatively long bristles, large, forwardly projecting axillae (lateral sections of the scutellum defined by grooves, close to the origins of the wings), and the absence of a linea calva (a linear patch lacking microsetae) on the fore wings (Hayat 1983). The antennae are typically eight-segmented with the last three segments forming a distinct club. One species, C. semiatratus, was described as having only a two-segmented club but Hayat (1983) questioned whether this might be an error.
The habits of many Coccophagus species remain little known but those we do know about show a remarkable variation in life styles. Most attack soft scales of the family Coccidae but a smaller number focus on mealybugs of the Pseudococcidae. Where things get odd is that male and female larvae develop differently (Askew 1971; Walter & Abeeluck 2006). In some species, males and females are both primary parasites of the same scale species but males develop as ectoparasites whereas females are endoparasites. In other species, male and female larvae are both endoparasites within the body of a scale but, while the females are primary parasites, the males are hyperparasites, feeding not directly on the scale but on the female larvae. And in yet other species, the male and female larvae may have separate hosts, with the males being hyperparasites on the larvae of different parasite species.
It should be remembered that wasps have a haplo-diploid system of sex determination, with females hatching from fertilised eggs whereas males hatch from fertilised eggs. As a result, females wasps can control how many they lay of each by whether they fertilise the egg or not before oviposition. In some species with hyperparasitic males, such as C. gurneyi, male and female eggs may be laid together though male eggs do not hatch until a suitable female host has developed. In other species, females lay male eggs on primary parasite hosts prior to mating, then switch to laying female eggs inside scale hosts after mating. It remains a question of some dispute to what degree males developing on conspecific females have distinct habits from males developing on different parasite species, or whether males will simply attack whatever primary parasite happens to be available.
Multiple Coccophagus species have been used in the biological control of pest scales. Coccophagus gurneyi, C. lycimnia and C. ochraceus have all been released outside their native ranges in the hopes that they will protect crops. Coccophagus scutellaris has similarly become distributed worldwide in association with humans, though I have not found whether this dispersal was deliberate or accidental. With the habits and hosts of so many Coccophagus species yet to be determined, you can be sure that this genus will continue to attract attention from hopeful horticulturalists.
Systematics of Coccophagus
Characters (Hayat 1983): Body moderately setose; antenna usually 8-segmented (1, 1, 3, 3), sometimes 7-segmented with 2-segmented clava; antennal scape not or only slightly flattened and not or hardly expanded beneath; scutellum with at least six setae, each axillae usually with at least two setae (rarely with just one); axillae large, subtriangular, strongly projecting forwards; separated mesally by about the maximum length of an axilla; scutellum not extending over base of gaster and metanotum without a membranous extension overlapping tergum I of gaster (several species have a thin transparent extension of the metanotum, which partly overlaps the propodeum in the middle); submarginal vein not enlarged; linea calva absent; hypopygium not pointed at apex and not extending to apex of gaster.
Coccophagus Westwood 1833 (see below for synonymy)H83
|--*C. scutellaris (Dalman 1825)H83, W39 (see below for synonymy)
|--C. acanthoscelesH83
|--C. aethiopis Girault 1935 [=Prospaltella berlesei Silvestri 1930 non (Howard 1906)]G35
|--C. aethochreusH83
|--C. amblydonH83
|--C. antiopa Girault 1915GM79
|--C. argentifascia Girault 1915GM79
|--C. atratusH83
|--C. auricaput Girault 1915GM79
|--C. bartlettiH83
|--C. basalisA71
|--C. bivittatusA71
|--C. brahmsi Girault 1933G33b
|--C. brimblecombei Girault 1933G33a
|--C. capensisA71
|--C. carideiA71 [=*Onophilus carideiH83]
|--‘*Aneristus’ ceroplastaeH83
|--C. coccidis Girault 1917G17
|--C. conditusH83
|--C. cowperi Girault 1917G17
|--C. croconotusH83
|--C. crucigerus Girault 1931G31
|--C. diachraeusH83
|--C. exiguiventris Girault 1929G29
|--C. flavoscutellum Ashmead 1881GM79
|--C. grotei Girault 1931G31
|--C. gurneyiA71
|--C. herndoni Girault 1935 [=Prospaltella aurantii Silvestri 1930 non Coccophagus aurantii Howard 1894]G35
|--C. immaculatus Howard 1881GM79
|--C. inkermani Girault 1926G26b
|--C. inlacertus Girault 1931G31
|--C. insidiatorA71
|--C. iris Girault 1930G30b
|--C. krygeri [=*Parencarsia krygeri]H83
|--C. lecanii Fitch 1858GM79
|--‘*Paracharitopus lecanii’ non Coccophagus lecanii Fitch 1858H83
|--C. leucippi Girault 1936G36b
|--C. longifasciatusA71
|--C. lucani Girault 1922GM79
|--C. lunulatus Howard 1894GM79
|--C. lutescensH83
|--C. lycimniaA71
|--C. malthusi Girault 1917G17
|--C. maria Girault 1931G31
|--C. marxi Girault 1936G36a
|--C. mexicensis Girault 1917G17
|--C. modesta Silvestri 1914GM79
|--C. multisetae Girault 1931G31
|--C. nigritusA71
|--C. nigriventris (Girault 1913)GM79
|--C. nigropleurum Girault 1917G17
|--C. ochraceusA71
|--C. perhispidus Westwood 1833GM79
|--C. pulchrus [=*Ataneostigma pulchra]H83
|--C. pulcini Girault 1926G26b
|--C. quaestor Girault 1917G17
|--C. redini Girault 1924G24
|--C. rosae [=C. (*Polycoccophagus) rosae]H83
|--C. rustiMH11
|--C. saintebeauvei Girault 1917G17
|--C. sanctus Girault 1928G28
|--C. semiatratus De Santis 1947 [=*Heptacritus semiatratus]H83
|--C. seminigriclavus Girault 1913GM79
|--C. shakespearella Girault 1929G29
|--C. signus Girault 1920GM79
|--C. silvifilia Girault 1924G24
|--C. socratis Girault 1931G31
|--C. sophia Girault & Dodd 1915GM79
|--C. submetallicus Girault 1930G30b
|--C. subsignus Girault 1932G32b
|--C. taciti Girault 1930G30a
|--C. tennysoni Girault 1931G31
|--C. thoreauini Girault 1915GM79
|--C. totiaureus Girault 1930G30a
|--C. triangulatinotus Girault 1926G26b
|--C. triguttatus Girault 1915GM79
|--C. tristisG26a
|--C. unifasciata Girault 1915GM79
`--C. vegai Girault 1932G32a
Coccophagus Westwood 1833 [incl. Aneristus Howard 1895, Ataneostigma Girault 1914, Heptacritus De Santis 1960, Onophilus Brèthes 1918, Paracharitopus Brèthes 1913, Parencarsia Mercet 1930, Polycoccophagus Sugonjaev 1976; Coccophagini]H83
*Coccophagus scutellaris (Dalman 1825)H83, W39 [=Entedon scutellarisH83, Aphelinus scutellarisW39; incl. Eulophus flavovariusW39, Coccophagus pulchellus Westwood 1833W39]
*Type species of generic name indicated
References
[A71] Askew, R. R. 1971. Parasitic Insects. Heinemann Educational Books: London.
[G17] Girault, A. A. 1917. Descriptiones stellarum novarum. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 80–101).
[G24] Girault, A. A. 1924. Homo perniciosus and new Hymenoptera. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 178–181).
[G26a] Girault, A. A. 1926a. New pests from Australia. II. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 200–202).
[G26b] Girault, A. A. 1926b. New pests from Australia. III. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 203–204).
[G28] Girault, A. A. 1928. Some Insecta and a new All Highness. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 225–228).
[G29] Girault, A. A. 1929. Description of a case of lunacy in Homo and of six-legged articulates. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 262–265).
[G30a] Girault, A. A. 1930a. New pests from Australia. VII. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 270–272).
[G30b] Girault, A. A. 1930b. New pests from Australia. VIII. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 273–277).
[G31] Girault, A. A. 1931. A new habit in an old insect, Homo pudicus and new Eurytomidae. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 280–283).
[G32a] Girault, A. A. 1932a. New pests from Australia, X. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 286–291).
[G32b] Girault, A. A. 1932b. New lower Hymenoptera from Australia and India. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 293–298).
[G33a] Girault, A. A. 1933a. Some beauties inhabitant not of commercial boudoirs but of Nature’s bosom, notably new insects. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 299–303).
[G33b] Girault, A. A. 1933b. Some beauties inhabitant not of the boudoirs of commerce but of Nature’s bosom—new insects. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 304–305).
[G35] Girault, A. A. 1935. Microhymenoptera Australiensis nova, mostly Chalcididae. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 315–318).
[G36a] Girault, A. A. (as ‘L. de St. Fargeau’). 1936a. Chalcididae, Capsidae species nova Australiensis Giraulti. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 319–321).
[G36b] Girault, A. A. 1936b. Terror-errors; and novitates of Pterygota (or earth realities not state-bound). Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 322–325).
[GM79] Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 1–400.
[H83] Hayat, M. 1983. The genera of Aphelinidae (Hymenoptera) of the world. Systematic Entomology 8: 63–102.
[MH11] Munro, J. B., J. M. Heraty, R. A. Burks, D. Hawks, J. Mottern, A. Cruaud, J.-Y. Rasplus & P. Jansta. 2011. A molecular phylogeny of the Chalcidoidea (Hymenoptera). PloS One 6 (11): e27023.
[W39] Walker, F. 1839. Monographia Chalciditum vol. 1. Hyppolitus Ballière: London.
Walter, G. H., & D. Abeeluck. 2006. Confirmation of the existence of alloparasitoids in nature—host relationships of an Australian Coccophagus species that parasitizes mealy bugs. Entomologia Experimentalis et Applicata 118: 97–103.