A new species of mealybug (Hemiptera: Coccomorpha: Pseudococcidae) from Tectona grandis L.f. (Lamiaceae) in southern India.

A new species of mealybug, Formicococcus tectonae Joshi, Bindu Gullan sp. n., is described and illustrated based on adult females collected from teak, Tectona grandis (Lamiaceae), in plantations in Thrissur district, Kerala, southern India. The mealybug lives in tunnels made by the teak trunk borer, Cossus cadambae (Moore) (Lepidoptera: Cossidae). Ants of a Tapinoma species were found in the tunnels, tending the mealybugs. The new mealybug is most similar morphologically to F. polysperes Williams and F. robustus (Ezzat McConnell) comb. rev. A key to adult females of all the Formicococcus species recorded from India is provided.

A revision of Lachnodius Maskell (Hemiptera, Coccomorpha, Eriococcidae).

Lachnodius Maskell is a genus of three named species that are part of an Australian radiation of felt scale insects that induce galls on Eucalyptus and Corymbia (Myrtaceae). A female's gall usually consists of an open-top pit in swollen plant tissue. Depending on the species, galls can occur on a host's leaves, buds, stems, or trunk. Here, we redescribe the named species: L.eucalypti (Maskell), L.hirsutus (Froggatt) and L.lectularius (Maskell), and describe seven new species: L.brimblecombei Beardsley, Gullan & Hardy, sp. n., L.froggatti Beardsley, Gullan & Hardy, sp. n., L.maculosus Beardsley, Gullan & Hardy, sp. n., L.melliodorae Beardsley, Gullan & Hardy, sp. n., L.newi Beardsley, Gullan & Hardy, sp. n., L.parathrix Beardsley, Gullan & Hardy, sp. n., L.sealakeensis Gullan & Hardy, sp. n. Descriptions are based primarily on adult females, but for some species short diagnoses of nymphal stages also are provided. The taxonomic history of Lachnodius is reviewed, with notes on their biology and ecology. A key to species based on the morphology of adult females is provided, and lectotypes are designated for Dactylopiuseucalypti Maskell and Lachnodiuslectularius Maskell.

A newly recognised species of Cryptes Maskell 1892 (Hemiptera: Coccidae) from Western Australia.

Cryptes utzoni Lin, Kondo Cook sp. n. (Hemiptera: Coccidae) is described based on adult female morphology and DNA sequences from mitochondrial and nuclear loci. This Australian endemic species was found on the stem of Acacia aneura (Fabaceae) in Western Australia. All phylogenetic analyses of three independent DNA loci show that C. utzoni is closely related to C. baccatus (Maskell), the type and only species of Cryptes Maskell, 1892. The adult female of C. utzoni is described and illustrated and a table is provided of the characters that differ among adult females of the two species of Cryptes now recognised (C. baccatus and C. utzoni) and a morphologically similar Western Australian species, Austrolichtensia hakearum (Fuller). There is deep genetic divergence in COI among samples of C. baccatus, suggesting the possibility of a species complex in this taxon.

Taxonomy of coccids (Hemiptera: Coccidae: Coccus L.) associated with Crematogaster ants (Hymenoptera: Formicidae) in the stems of Macaranga plants (Euphorbiaceae) in Southeast Asia.

The Southeast Asian soft scale insects (Hemiptera: Coccomorpha: Coccidae) associated with ants of the Crematogaster borneensis-group (Hymenoptera: Formicidae) and living in the hollow stems of Macaranga plants (Euphorbiaceae) are revised taxonomically. Ten species of the genus Coccus L. are recognised: seven were described previously and three new species are described herein. The species are: Coccus caviramicolus Morrison, C. circularis Morrison, C. heckrothi Gullan Kondo sp. n., C. lambirensis Gullan Kondo sp. n., C. macarangicolus Takahashi, C. macarangae Morrison, C. penangensis Morrison, C. pseudotumuliferus Gullan Kondo sp. n., C. secretus Morrison and C. tumuliferus Morrison. All of these species are described or redescribed and newly illustrated based on the adult females, and a key to distinguish the species is provided. We designate a lectotype for C. macarangicolus. The first-instar nymphs of all species are morphologically extremely similar and therefore only the first-instar nymph of C. macarangae is described and illustrated. Seven of these species currently are known only from Macaranga, but C. macarangae, C. secretus and perhaps C. pseudotumuliferus have been recorded from the hollow stems of several other ant-plants and a few non-myrmecophytes. The Coccus species from Macaranga are closely related to C. hesperidum L., the type species of the genus, and therefore are retained in the genus Coccus even though the adult females exhibit a few morphological differences from C. hesperidum. The species of Coccus from Macaranga appear to be parthenogenetic because no male nymphs or adults have been found, despite extensive collecting.

Nomenclatural changes in the Australasian gall-inducing genus Apiomorpha Rübsaamen (Hemiptera: Coccomorpha: Eriococcidae).

Apiomorpha Rübsaamen, 1894 was erected as a replacement name for Brachyscelis Schrader, 1863 that was preoccupied in the Coleoptera (Chrysomelidae: Brachyscelis Germar, 1834). Apiomorpha is a genus of eriococcid scale insects that induce galls on Eucalyptus (Myrtaceae) in Australia and New Guinea (Szent-Ivany & Womersley 1962; Gullan 1984; Gullan et al. 2005). In his original description of the genus, Schrader (1863a) included six species, of which B. citricola Schrader was subsequently recognised as a nomen nudum (Froggatt 1921). Among the other five, B. pileata Schrader was later designated as the type species of Apiomorpha by Lindinger (1937). Also amongst these five was B. ovicola Schrader, for which Schrader described and illustrated galls of males and females on twigs and leaves of Eucalyptus haemastoma (Schrader 1863a, plate II, figs a, e) in or near Sydney, New South Wales (NSW). He stated that his species names reflected the shape of the galls of adult females; hence those of B. ovicola can be interpreted as being egg-shaped and were illustrated as such by Schrader (1863a). Galls of males of B. ovicola he described and illustrated as trumpet-shaped.

A newly recognised Australian endemic species of Austrolecanium Gullan & Hodgson 1998 (Hemiptera: Coccidae) from Queensland.

Austrolecanium cryptocaryae Lin & Cook sp. n. is described based on adult female morphology and DNA sequences from mitochondrial and nuclear loci. This Australian endemic species was found on the underside of leaves of Cryptocarya microneura (Lauraceae) in Queensland. All phylogenetic analyses of four independent DNA loci and a concatenated dataset show that A. cryptocaryae is monophyletic and closely related to A. sassafras Gullan & Hodgson, the type species of Austrolecanium Gullan & Hodgson. The adult female of A. cryptocaryae is described and illustrated and a table is provided of the characters that differ among adult females of the three species of Austrolecanium currently recognised (A. cappari (Froggatt), A. cryptocaryae sp. n. and A. sassafras).

A new pupillarial scale insect (Hemiptera: Coccoidea: Eriococcidae) from Angophora in coastal New South Wales, Australia.

A new scale insect, Aolacoccus angophorae gen. nov. and sp. nov. (Eriococcidae), is described from the bark of Angophora (Myrtaceae) growing in the Sydney area of New South Wales, Australia. These insects do not produce honeydew, are not ant-tended and probably feed on cortical parenchyma. The adult female is pupillarial as it is retained within the cuticle of the penultimate (second) instar. The crawlers (mobile first-instar nymphs) emerge via a flap or operculum at the posterior end of the abdomen of the second-instar exuviae. The adult and second-instar females, second-instar male and first-instar nymph, as well as salient features of the apterous adult male, are described and illustrated. The adult female of this new taxon has some morphological similarities to females of the non-pupillarial palm scale Phoenicococcus marlatti Cockerell (Phoenicococcidae), the pupillarial palm scales (Halimococcidae) and some pupillarial genera of armoured scales (Diaspididae), but is related to other Australian Myrtaceae-feeding eriococcids.

The taxonomy of the Japanese oak red scale insect, Kuwania quercus (Kuwana) (Hemiptera: Coccoidea: Kuwaniidae), with a generic diagnosis, a key to species and description of a new species from California.

The oak red scale insect, Kuwania quercus (Kuwana), was described from specimens collected from the bark of oak trees (Quercus species) in Japan. More recently, the species has been identified from California and China, but Californian specimens differ morphologically from Japanese material and are considered here to be a new species based on both morphological and molecular data. In this paper, an illustrated redescription of K. quercus is provided based on type specimens consisting of adult females, first-instar nymphs and intermediate-stage females, and a lectotype is designated for Sasakia quercus Kuwana. The new Californian species, Kuwania raygilli Wu & Gullan, is described and illustrated based on the adult female, first-instar nymph and intermediate-stage female. A new generic diagnosis for Kuwania Cockerell based on adult females and first-instar nymphs, and a key to species based on adult females are included.

Evolutionary relationships among primary endosymbionts of the mealybug subfamily phenacoccinae (hemiptera: Coccoidea: Pseudococcidae).

Mealybugs (Coccoidea: Pseudococcidae) are sap-sucking plant parasites that harbor bacterial endosymbionts within specialized organs. Previous studies have identified two subfamilies, Pseudococcinae and Phenacoccinae, within mealybugs and determined the primary endosymbionts (P-endosymbionts) of the Pseudococcinae to be Betaproteobacteria ("Candidatus Tremblaya princeps") containing Gammaproteobacteria secondary symbionts. Here, the P-endosymbionts of phenacoccine mealybugs are characterized based on 16S rRNA from the bacteria of 20 species of phenacoccine mealybugs and four outgroup Puto species (Coccoidea: Putoidae) and aligned to more than 100 published 16S rRNA sequences from symbiotic and free-living bacteria. Phylogenetic analyses recovered three separate lineages of bacteria from the Phenacoccinae, and these are considered to be the P-endosymbionts of their respective mealybug hosts, with those from (i) the mealybug genus Rastrococcus belonging to the Bacteroidetes, (ii) the subterranean mealybugs, tribe Rhizoecini, also within Bacteroidetes, in a clade sister to cockroach endosymbionts (Blattabacterium), and (iii) the remaining Phenacoccinae within the Betaproteobacteria, forming a well-supported sister group to "Candidatus Tremblaya princeps." Names are proposed for two strongly supported lineages: "Candidatus Brownia rhizoecola" for P-endosymbionts of Rhizoecini and "Candidatus Tremblaya phenacola" for P-endosymbionts of Phenacoccinae excluding Rastrococcus and Rhizoecini. Rates of nucleotide substitution among lineages of Tremblaya were inferred to be significantly faster than those of free-living Betaproteobacteria. Analyses also recovered a clade of Gammaproteobacteria, sister to the P-endosymbiont lineage of aphids ("Candidatus Buchnera aphidicola"), containing the endosymbionts of Putoidae, the secondary endosymbionts of pseudococcine mealybugs, and the endosymbionts of several other insect groups.

Australian gall-inducing scale insects on Eucalyptus: revision of Opisthoscelis Schrader (Coccoidea, Eriococcidae) and descriptions of a new genus and nine new species.

We revise the genus Opisthoscelis Schrader, and erect the genus Tanyscelisgen. n. with Opisthoscelis pisiformis Froggatt as its type species. Species of both genera induce sexually dimorphic galls on Eucalyptus (Myrtaceae) in Australia, with Opisthoscelis subrotunda Schrader also in Papua New Guinea. We synonymise the following taxa (junior synonym with senior synonym): Opisthoscelis fibularis Froggatt, syn. n. with Opisthoscelis spinosa Froggatt; Opisthoscelis recurva Froggatt, syn. n. with Opisthoscelis maculata Froggatt; Opisthoscelis globosa Froggatt, syn. n. (= Opisthoscelis ruebsaameni Lindinger) with Opisthoscelis convexa Froggatt; and Opisthoscelis mammularis Froggatt, syn. n. with Opisthoscelis verrucula Froggatt. We transfer seven Opisthoscelis species to Tanyscelis as Tanyscelis conica (Fuller), comb. n., Tanyscelis convexa (Froggatt), comb. n., Tanyscelis maculata (Froggatt), comb. n., Tanyscelis maskelli (Froggatt), comb. n., Tanyscelis pisiformis (Froggatt), comb. n., Tanyscelis spinosa (Froggatt), comb. n., and Tanyscelis verrucula (Froggatt), comb. n. We redescribe and illustrate the adult female of each named species of Opisthoscelis for which the type material is known, as well as the first-instar nymph of the type species of Opisthoscelis (Opisthoscelis subrotunda) and Tanyscelis (Opisthoscelis pisiformis). We describe four new species of Opisthoscelis: Opisthoscelis beardsleyi Hardy & Gullan, sp. n., Opisthoscelis thurgoona Hardy & Gullan, sp. n., Opisthoscelis tuberculataHardy & Gullan, sp. n., and Opisthoscelis ungulifinis Hardy & Gullan, sp. n., and five new species of Tanyscelis: Tanyscelis grallator Hardy & Gullan, sp. n., Tanuscelis megagibba Hardy & Gullan, sp. n., Tanyscelis mollicornuta Hardy & Gullan, sp. n., Tanyscelis tripocula Hardy & Gullan, sp. n., and Tanyscelis villosigibba Hardy & Gullan, sp. n. We designate lectotypes for Opisthoscelis convexa, Opisthoscelis fibularis, Opisthoscelis globosa Froggatt, Opisthoscelis maculata, Opisthoscelis mammularis, Opisthoscelis maskelli, Opisthoscelis pisiformis, Opisthoscelis recurva, Opisthoscelis serrata, Opisthoscelis spinosa, and Opisthoscelis verrucula. As a result of our taxonomic revision, Opisthoscelis has six species and Tanyscelis has 12 species. We describe the galls of females for all 18 species and galls of males for 10 species of Opisthoscelis and Tanyscelis, and provide photographs of the galls for most species. A key to the adult females of the species of both genera is included.

Synonymy of Plotococcus Miller & Denno with Leptococcus Reyne, and description of a new species from Colombia (Hemiptera: Pseudococcidae).

Plotococcus Miller & Denno is synonymized with Leptococcus Reyne (Coccoidea: Pseudococcidae). The genus is redescribed and the adult female of the type species, L. metroxyli Reyne, is redescribed and illustrated. All species hitherto included in Plotococcus are transferred to Leptococcus as L. capixaba (Kondo) comb. nov., L. eugeniae (Miller & Denno) comb. nov., L. hambletoni (Kondo) comb. nov., L. minutus (Hempel) comb. nov., and L. neotropicus (Williams & Granara de Willink) comb. nov. A new species of Leptococcus, L. rodmani Kondo sp. n., from leaves of Guarea guidonia (Meliaceae) from Colombia, is described and illustrated based on the adult female. A revised key to adult females of all species in the genus is provided.

Synonymy of Plotococcus Miller & Denno with Leptococcus Reyne, and description of a new species from Colombia (Hemiptera: Pseudococcidae)

Plotococcus Miller & Denno is synonymized with Leptococcus Reyne (Coccoidea: Pseudococcidae). The genus is redescribed and the adult female of the type species, L. metroxyli Reyne, is redescribed and illustrated. All species hitherto included in Plotococcus are transferred to Leptococcus as L. capixaba (Kondo) comb. nov., L. eugeniae (Miller & Denno) comb. nov., L. hambletoni (Kondo) comb. nov., L. minutus (Hempel) comb. nov., and L. neotropicus (Williams & Granara de Willink) comb. nov. A new species of Leptococcus, L. rodmani Kondo sp. n., from leaves of Guarea guidonia (Meliaceae) from Colombia, is described and illustrated based on the adult female. A revised key to adult females of all species in the genus is provided.

Plotococcus Miller & Denno é sinonimizado com Leptococcus Reyne. O gênero é rediagnosticado é a espécie tipo, L. metroxyli Reyne, é diagnosticada e ilustrada. Todas as espécies até agora incluídas em Plotococcus são transferidas a Leptococcus como: L. capixaba (Kondo), comb. nov., L. eugeniae (Miller & Denno) comb. nov., L. hambletoni (Kondo) comb. nov., L. minutus (Hempel) comb. nov., é L. neotropicus (Williams & Granara de Willink) comb. nov. Uma nova espécie de Leptococcus,L. rodmani Kondo sp. n., coletada nas folhas do Guarea guidonia (Meliaceae) na Colômbia, é descrita e ilustrada com base na fêmea adulta. Uma chave revisada para todas as espécies no gênero é fornecida.

Coccidae, Pseudococcidae, Ortheziidae, and Monophlebidae (Hemiptera: Coccoidea) of Espírito Santo, Brazil / Coccidae, Pseudococcidae, Ortheziidae, e Monophlebidae (Hemiptera: Coccoidea) do Espírito Santo, Brasil

New plant hosts are recorded for nine scale insect species recently collected in Espírito Santo, Brazil, and eleven scale insect species are recorded for the first time from the state: Ceroplastes floridensis Comstock, Coccus longulus (Douglas), Coccus viridis (Green), Eucalymnatus tesselatus (Signoret), Pseudokermes sp., Saissetia coffeae (Walker), Phenacoccus madeirensis Green, Pseudococcus jackbeardsleyi Gimpel & Miller, Pseudococcus longispinus (Targioni Tozzetti), Icerya purchasi Maskell, and Icerya genistae Hempel. This is also the first record of Co. longulus in Brazil. Information on the host plants and geographic distribution of the 26 species of scale insects of the families Coccidae, Pseudococcidae, Ortheziidae, and Monophlebidae, currently known from Espírito Santo is provided.

Novas plantas hospedeiras foram registradas para nove espécies de cochonilhas coletadas recentemente no Estado do Espírito Santo, Brasil, e onze espécies de cochonilhas são registradas pela primeira vez no Estado: Ceroplastes floridensis Comstock, Coccus longulus (Douglas), Coccus viridis (Green), Eucalymnatus tesselatus (Signoret), Pseudokermes sp., Saissetia coffeae (Walker), Phenacoccus madeirensis Green, Pseudococcus jackbeardsleyi Gimpel & Miller, Pseudococcus longispinus (Targioni Tozzetti), Icerya purchasi Maskell, e Icerya genistae Hempel. Co. longulus é registrada pela primeira vez no Brasil. É disponibilizada a informação das plantas hospedeiras e a distribuição geográfica de 26 espécies de cochonilhas das famílias Coccidae, Pseudococcidae, Ortheziidae, e Monophlebidae atualmente conhecidas no Estado do Espírito Santo.

First records of two mealybug species in Brazil and new potential pests of papaya and coffee.

Five mealybug (Hemiptera: Pseudococcidae) plant pest species: Dysmicoccus grassii (Leonardi), Ferrisia malvastra (McDaniel), Ferrisia virgata (Cockerell), Phenacoccus tucumanus Granara de Willink, and Pseudococcus elisae Borchsenius are recorded for the first time in the state of Espírito Santo, Brazil. These are the first records of D. grassii in Brazil, from papaya (Carica papaya, Caricaceae), and from coffee (Coffea canephora, Rubiaceae). Ferrisia malvastra is also newly recorded in Brazil, where it was found on Bidens pilosa (Asteraceae). Ferrisia virgata was collected from an unidentified weed and Phenacoccus tucumanus from Citrus sp. (Rutaceae). Plotococcus capixaba Kondo was found on pitanga ( Eugenia cf. pitanga, Myrtaceae) and Pseudococcus elisae on Coffea canephora , which are new host records for these mealybugs.

A new lac insect from Colombia, with revised keys to lac insect genera and to species of Austrotachardiella Chamberlin ( Hemiptera: Coccoidea: Kerriidae )

Uma nova espécie do inseto laca, Austrotachardiella colombiana Kondo & Gullan sp. n. (Kerriidae), é descrita e ilustrada com base na fêmea adulta. A espécie foi relatada causando a morte nos ramos e galhos de duas cultivares de Psidium guajava L. (Myrtaceae) em Santander de Quilichao, Cauca, Colômbia. Uma chave taxonômica revisada para os gêneros da família Kerriidae e uma chave atualizada para separar as espécies de Austrotachardiella Chamberlin são fornecidas. Não foram encontrados registros anteriores de insetos laca para a Colômbia.

A new species of ant-tended soft scale of the genus Cryptostigma Ferris (Hemiptera: Coccidae) associated with bamboo in Peru / Uma nova espécie de coccídeo do gênero Cryptostigma Ferris (Hemiptera: Coccidae) associada a formigas de bambu no Peru

Soft scale insects of the genus Cryptostigma Ferris (Coccidae: Myzolecaniinae) occur only in the Neotropical region and usually live in the nests of ants, or rarely bees, inside plant stems, or feed on plant roots. Here we provide the first report of Cryptostigma from Peru. We describe Cryptostigma guadua sp.n. based on the adult female and the first-instar nymph. These coccids have been collected only from the nests of Camponotus (Myrmostenus) longipilis Emery, C. (Myrmostenus) mirabilis Emery and Camponotus (Pseudocolobopsis) sp. (Formicidae: Formicinae) from inside live bamboos of Guadua sp. (Poaceae) in lowland tropical forest in Parque Nacional del Manu, in southeast Peru. The adult female and the first-instar nymph (crawler) of C. guadua sp. n. are compared to closely related species.

Os coccídeos do gênero Cryptostigma Ferris (Coccidae: Myzolecaniinae) ocorrem somente na região Neotropical e normalmente vivem em ninhos de formigas, ou raramente de abelhas, dentro de troncos, ou raízes de plantas. Neste trabalho, descreve-se pela primeira vez uma espécie de Cryptostigma coletada no Peru. A descrição de Cryptostigma guadua sp.n. é baseada na fêmea adulta e em ninfas do primeiro ínstar. Foram coletados em ninhos de Camponotus (Myrmostenus) longipilis Emery, C. (Myrmostenus) mirabilis Emery e Camponotus (Pseudocolobopsis) sp. (Formicidae: Formicinae), encontrados dentro de bambus vivos do gênero Guadua (Poaceae) planície de mata tropical do Parque Nacional del Manu, no sudeste do Peru. A fêmea adulta e a ninfa do primeiro ínstar de C. guadua sp.n. são comparadas com outras espécies próximas na taxonomia do grupo.

Phylogenetic evidence for two new insect-associated Chlamydia of the family Simkaniaceae.

On the basis of 16S-23S ribosomal DNA analyses, the whitefly Bemisia tabaci (Sternorrhyncha, Aleyrodidae) and the eriococcid Eriococcus spurius (Sternorrhyncha, Eriococcidae) were each found to harbor novel related chlamydial species within the family Simkaniaceae. The generic designation Fritscheagen. nov. is proposed to accommodate the two species, F. bemisiaesp. nov. and F. eriococci sp. nov. The finding of chlamydial 16S-23S ribosomal DNA in B. tabaci is consistent with a previous electron microscopy study which found that bacteriocytes of this species contain structures that we consider to resemble the elementary and reticulate bodies of chlamydia (Costa HS, Westcot DM, Ullman DE, Rosell R, Brown JK, Johnson MW. Protoplasma 189:194-202, 1995). The cloning and sequencing of a 16.6 kilobase DNA fragment from F. bemisiae indicated that it contains six genes encoding for proteins similar to those found in other species of chlamydia. These results extend the range of organisms that harbor chlamydia.

A preliminary phylogeny of the scale insects (Hemiptera: Sternorrhyncha: Coccoidea) based on nuclear small-subunit ribosomal DNA.

Scale insects (Hemiptera: Sternorrhyncha: Coccoidea) are a speciose and morphologically specialized group of plant-feeding bugs in which evolutionary relationships and thus higher classification are controversial. Sequences derived from nuclear small-subunit ribosomal DNA were used to generate a preliminary molecular phylogeny for the Coccoidea based on 39 species representing 14 putative families. Monophyly of the archaeococcoids (comprising Ortheziidae, Margarodidae sensu lato, and Phenacoleachia) was equivocal, whereas monophyly of the neococcoids was supported. Putoidae, represented by Puto yuccae, was found to be outside the remainder of the neococcoid clade. These data are consistent with a single origin (in the ancestor of the neococcoid clade) of a chromosome system involving paternal genome elimination in males. Pseudococcidae (mealybugs) appear to be sister to the rest of the neococcoids and there are indications that Coccidae (soft scales) and Kerriidae (lac scales) are sister taxa. The Eriococcidae (felt scales) was not recovered as a monophyletic group and the eriococcid genus Eriococcus sensu lato was polyphyletic.

Secondary (gamma-Proteobacteria) endosymbionts infect the primary (beta-Proteobacteria) endosymbionts of mealybugs multiple times and coevolve with their hosts.

Mealybugs (Hemiptera, Coccoidea, Pseudococcidae) are plant sap-sucking insects that have within their body cavities specialized cells containing prokaryotic primary endosymbionts (P-endosymbionts). The P-endosymbionts have the unusual property of containing within their cytoplasm prokaryotic secondary endosymbionts (S-endosymbionts) [C. D. von Dohlen, S. Kohler, S. T. Alsop, and W. R. McManus, Nature (London) 412:433-436, 2001]. Four-kilobase fragments containing 16S-23S ribosomal DNA (rDNA) were obtained from the P-endosymbionts of 22 mealybug species and the S-endosymbionts of 12 representative species. Phylogenetic analyses of the P-endosymbionts indicated that they have a monophyletic origin and are members of the beta-subdivision of the Proteobacteria; these organisms were subdivided into five different clusters. The S-endosymbionts were members of the gamma-subdivision of the Proteobacteria and were grouped into clusters similar to those observed with the P-endosymbionts. The S-endosymbiont clusters were distinct from each other and from other insect-associated bacteria. The similarity of the clusters formed by the P- and S-endosymbionts suggests that the P-endosymbionts of mealybugs were infected multiple times with different precursors of the S-endosymbionts and once the association was established, the P- and S-endosymbionts were transmitted together. The lineage consisting of the P-endosymbionts of mealybugs was given the designation "Candidatus Tremblaya" gen. nov., with a single species, "Candidatus Tremblaya princeps" sp. nov. The results of phylogenetic analyses of mitochondrial DNA fragments encoding cytochrome oxidase subunits I and II from four representative mealybug species were in agreement with the results of 16S-23S rDNA analyses, suggesting that relationships among strains of "Candidatus T. princeps" are useful in inferring the phylogeny of their mealybug hosts.

Sexual dichronism and intersexual phoresy in gall-forming coccoids.

Coccoid gall-formers from the genus Cystococcus exhibit sexual dichronism, producing the males of a brood well before their sisters. This ensures the coexistence in the maternal gall of winged adult males and their first instar wingless sisters. Females disperse by clinging to the attenuate abdomens of their brothers, and the efficiency of this dispersal is reflected in an even dispersion on host trees. Evolution of this form of phoresy may be associated with the paternal genome loss prevalent in the Coccoidea.