Coccidohystrix insolita (Green, 1908)

Moore, Aubrey, Watson, Gillian W. & Bamba, Jesse, 2014, First record of Eggplant Mealybug, Coccidohystrixinsolita (Hemiptera: Pseudococcidae), on Guam: Potentially a major pest, Biodiversity Data Journal 2, pp. 1042-1042 : 1042

Coccidohystrix insolita (Green, 1908)

Materials

Type status: Other material. Occurrence: catalogNumber: AM20131204.002 ; occurrenceRemarks: on eggplant leaves; recordedBy: Jesse Bamba; sex: 7 slide-mounted adult females were examined; Location: islandGroup: Mariana Islands; island: Guam; municipality: Dededo; locality: near Swamp Road ; decimalLatitude: 13.539981; decimalLongitude: 144.83435; Identification: identifiedBy: Gillian W. Watson; dateIdentified: 2013-12-13; Event: samplingProtocol: eggplant leaf samples; eventDate: 2013-12-04; Record Level: collectionID: ESUG; institutionCode: UGUAM; basisOfRecord: LivingSpecimen; source: http://guaminsects.myspecies.info/node/2623

Diagnosis

9-segmented; posterior ostioles present, anterior ostioles absent; cerarii on margins numbering 17 pairs, numerous dorsal cerarii present also, each cerarius consisting of 1-15 large conical setae situated on a sclerotized prominence, without any associated trilocular pores; legs well developed, each claw with a denticle present on plantar surface; circulus absent; anal lobes well developed, each with a sclerotized ventral bar; quinquelocular pores numerous on venter; multilocular disc pores numerous on venter of abdominal segments III-IX, a few also present on the venter of segments I and II and on the dorsum of segment VII; ventral oral collar ducts present on submargins of abdominal segments V-VIII; oral rim ducts absent entirely.

Diagnosis was based Williams 2004 which includes a good taxonomic illustration of Coccidohystrix insolita .

Distribution

Coccidohystrix insolita has been recorded in the literature from the following regions and countries:

Afrotropical: Kenya, Madagascar, Rodriques Island (Mauritius), South Africa, Tanzania, Zanzibar; Australasian: Western Samoa; Oriental: Bangladesh, Burma (=Myanmar), India, Laos, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; Palaearctic: China, Saudi Arabia ( Ben-Dov 2013).

In addition, a Japanese quarantine inspector found Coccidohystrix insolita on Alternanthera ( Amaranthaceae ) imported from Singapore ( Tokihiro 2006).

Prior to our discovery on Guam, Coccidohystrix insolita was known only from two Pacific island nations: the Philippines and Western Samoa. Coccidohystrix insolita was first detected in the Philippines during 1994 ( Lit et al. 1998) and in Western Samoa in 1966 ( Williams and Watson 1988).

Biology

Coccidohystrix insolita lives on the leaves (Fig. 3).

Notes

The appearance of Coccidohystrix insolita in life is unusual for a mealybug because the adult female has very little dorsal wax and secretes a white, waxy ovisac up to 6 times as long as the body of the female (Fig. 1), which is more typical of some Coccidae . The immature stages do not secrete a thick layer of mealy wax, the body being shiny yellow-green with submedian grey spots on 2 abdominal and 1 thoracic segments (Fig. 2). This contrasts with the in life appearance of the solenopsis mealybug, Phenacoccus solenopsis Tinsley, in which all developmental stages develop a thick layer of white mealy wax except for two longitudinal lines of bare cuticle that expose dark submedian spots on 3 or 4 segments on the abdomen and 1 or 2 on the thorax.

Host Plants

Coccidohystrix insolita is polyphagous and is recorded from the following families of host plants ( Ben-Dov 2013): Acanthaceae , Amaranthaceae , Apocynaceae , Araceae , Arecaceae , Aristolochiaceae , Asteraceae , Chenopodiaceae , Cucurbitaceae , Euphorbiaceae , Fabaceae , Malvaceae , Menispermaceae , Moraceae , Poaceae , Rhamnaceae , Rubiaceae , Solanaceae , Sterculiaceae , Tiliaceae , Zygophyllaceae .

Many plants belonging to these families are important to agriculture and forestry on Guam.

Parasitoids

Twenty-three species of hymenopterous parasitoids are associated with Coccidohystrix insolita ( Noyes 2013):

Aphelinidae : Coccophagus pseudococci ; Encyrtidae : Adektitopus longipennis , Anagyrus gracilis , Apoleptomastix bicoloricornis , Blepyrus insularis , Gyranusoidea signata , Homalotylus albiclavatus , Homalotylus hemipterinus , Homalotylus indicus , Homalotylus turkmenicus , Leptomastix nigrocincta , Leptomastix nigrocoxalis , Neocharitopus orientalis , Paranathrix tachikawai , Prochiloneurus albifuniculus , Prochiloneurus pulchellus ; Eulophidae : Aprostocetus ajmerensis , Aprostocetus annulicornis , Aprostocetus jaipurensis ; Pteromalidae : Catolaccus crassiceps ; Signiphoridae : Chartocerus hyalipennis , Chartocerus kerrichi , Chartocerus kurdjumovi .

None of these species are known to exist on Guam and there were no signs of parasitism in the specimens examined.

Other Natural Enemies

The following natural enemies have been recorded attacking Coccidohystrix insolita : Fungi: Metarhizium anisopliae ; Insecta: Coleoptera : Coccinellidae : Anegleis cardoni (Weise); Hyperaspis maindronia ; Nephus regularis ; Lepidoptera : Lycaenidae : Spalgis epeus ( Ben-Dov 2013). None of the insect predators are known to exist on Guam.

Attendant Ants

Three species of attendant ants are associated with Coccidohystrix insolita : Dolichoderus bituberculatus, Solenopsis geminata , Anoplolepis gracilipes ( Ben-Dov 2013). The latter two species are abundant on Guam but so far, we have not yet seen any ant associations with Coccidohystrix insolita .