Functional analysis of the Alternaria brassicicola non-ribosomal peptide synthetase gene AbNPS2 reveals a role in conidial cell wall construction

Alternaria brassicicola is a necrotrophic pathogen causing black spot disease on virtually all cultivated Brassica crops worldwide. In many plant pathosystems fungal secondary metabolites derived from non-ribosomal peptide synthetases (NPSs) are phytotoxic virulence factors or are antibiotics thought to be important for niche competition with other micro-organisms. However, many of the functions of NPS genes and their products are largely unknown. In this study, we investigated the function of one of the A. brassicicola NPS genes, AbNPS2 . The predicted amino acid sequence of AbNPS2 showed high sequence similarity with A. brassicae , AbrePsy1, Cochliobolus heterostrophus , NPS4 and a Stagonospora nodorum NPS. The AbNPS2 open reading frame was predicted to be 22 kb in length and encodes a large protein (7195 amino acids) showing typical NPS modular organization. Gene expression analysis of AbNPS2 in wild-type fungus indicated that it is expressed almost exclusively in conidia and conidiophores, broadly in the reproductive developmental phase. AbNPS2 gene disruption mutants showed abnormal spore cell wall morphology and a decreased hydrophobicity phenotype. Conidia of abnps2 mutants displayed an aberrantly inflated cell wall and an increase in lipid bodies compared with wild-type. Further phenotypic analyses of abnps2 mutants showed decreased spore germination rates both in vitro and in vivo , and a marked reduction in sporulation in vivo compared with wild-type fungus. Moreover, virulence tests on Brassicas with abnps2 mutants revealed a significant reduction in lesion size compared with wild-type but only when aged spores were used in experiments. Collectively, these results indicate that AbNPS2 plays an important role in development and virulence.     

Data partitioning in Bayesian analysis: molecular phylogenetics of metalmark moths (Lepidoptera: Choreutidae)

In this study a multilocus phylogenetic analysis of metalmark moths (Lepidoptera: Choreutidae) focused on resolving the higher‐level phylogeny of this group is presented. Through the analysis of this dataset, I explore different data‐partitioning strategies in Bayesian phylogenetic inference, and find that a partitioning strategy can have a large influence on the results of phylogenetic analysis. Depending on how the data are partitioned, there can be significant differences in branch support. I also test for the existence of the Bayesian star tree paradox, and its importance in this dataset, and find that it appears to inflate support for the clade including Rhobonda gaurisana, Hemerophila houttuinialis, H. diva and H. felis, but plays no role in other cases where the differences between maximum‐likelihood bootstraps and Bayesian posterior probabilities are large. The results of all the phylogenetic analyses strongly suggest that including Millieriinae in Choreutidae renders the family polyphyletic. The monophyly of the other two subfamilies, Brenthiinae and Choreutinae, as well as their sister‐group relationship, is strongly supported. Similarly, the monophyly of all the genera examined except Hemerophila is also well supported. To bring the classification of Choreutidae in line with our current understanding of the phylogenetic relationships in the family, I propose to exclude Millieriinae from Choreutidae, elevate it to Millieriidae Heppner, and place it as incertae sedis within Ditrysia.     

A molecular phylogeny for the oldest (nonditrysian) lineages of extant Lepidoptera,with implications for classification,comparative morphology and life‐history evolution

Within the insect order Lepidoptera (moths and butterflies), the so‐called nonditrysian superfamilies are mostly species‐poor but highly divergent, offering numerous synapomorphies and strong morphological evidence for deep divergences. Uncertainties remain, however, and tests of the widely accepted morphological framework using other evidence are desirable. The goal of this paper is to test previous hypotheses of nonditrysian phylogeny against a data set consisting of 61 nonditrysian species plus 20 representative Ditrysia and eight outgroups (Trichoptera), nearly all sequenced for 19 nuclear genes (up to 14 700 bp total). We compare our results in detail with those from previous studies of nonditrysians, and review the morphological evidence for and against each grouping The major conclusions are as follows. (i) There is very strong support for Lepidoptera minus Micropterigidae and Agathiphagidae, here termed Angiospermivora, but no definitive resolution of the position of Agathiphagidae, although support is strongest for alliance with Micropterigidae, consistent with another recent molecular study. (ii) There is very strong support for Glossata, which excludes Heterobathmiidae, but weak support for relationships among major homoneurous clades. Eriocraniidae diverge first, corroborating the morphological clade Coelolepida, but the morphological clades Myoglossata and Neolepidoptera are never monophyletic in the molecular trees; both are contradicted by strong support for Lophocoronoidea + Hepialoidea, the latter here including Mnesarchaeoidea syn.n. (iii) The surprising grouping of Acanthopteroctetidae + Neopseustidae, although weakly supported here, is consistent with another recent molecular study. (iv) Heteroneura is very strongly supported, as is a basal split of this clade into Nepticuloidea + Eulepidoptera. Relationships within Nepticuloidea accord closely with recent studies based on fewer genes but many more taxa. (v) Eulepidoptera are split into a very strongly supported clade consisting of Tischeriidae + Palaephatidae + Ditrysia, here termed Euheteroneura, and a moderately supported clade uniting Andesianidae with Adeloidea. (vi) Relationships within Adeloidea are strongly resolved and Tridentaformidae fam.n. is described for the heretofore problematic genus Tridentaforma Davis, which is strongly supported in an isolated position within the clade. (vii) Within Euheteroneura, the molecular evidence is conflicting with respect to the sister group to Ditrysia, but strongly supports paraphyly of Palaephatidae. We decline to change the classification, however, because of strong morphological evidence supporting palaephatid monophyly. (viii) We review the life histories and larval feeding habits of all nonditrysian families and assess the implications of our results for hypotheses about early lepidopteran phytophagy. The first host record for Neopseustidae, which needs confirmation, suggests that larvae of this family may be parasitoids. This published work has been registered in ZooBank: http://zoobank.org/urn:lsid:zoobank.org:pub:C17BB79B‐EF8F‐4925‐AFA0‐2FEF8AC32876 .     

A new extant family of primitive moths from Kangaroo Island,Australia, and its significance for understanding early Lepidoptera evolution

We report the first discovery since the 1970s of a new extant family (Aenigmatineidae fam.n. ) of homoneurous moths, based on the small Aenigmatinea glatzella sp.n . from Kangaroo Island off southern Australia. It exhibits a combination of extraordinary anatomical characters, and, unlike most homoneurous moths, its larva is a conifer‐feeder (stem mining in Callitris, Cupressaceae). While the adult's mouthparts are strongly regressed, evidence from other morphological characters and from a Bayesian analysis of 25 genetic loci convincingly places the taxon among Glossata (‘tongue moths’). An unexpected tongue moth clade including Acanthopteroctetidae and Neopseustidae, suggested with low support in recent molecular analyses, remarkably becomes strongly supported when Aenigmatinea is included in the molecular analysis; the new taxon becomes subordinated in that clade (as sister group to Neopseustidae) and the clade itself appears as the sister group of all Heteroneura, representing the vast majority of all Lepidoptera. Including Aenigmatinea into the analysis thereby strengthens the surprising indication of non‐monophyly of Myoglossata, and the new phylogeny requires an additional number of ad hoc assumptions of convergence/character reversals in early Lepidoptera evolution. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:44393B52‐1889‐431A‐AB08‐6BBCF8F946B8 .     

Relationships within the Melitaea phoebe species group (Lepidoptera: Nymphalidae): new insights from molecular and morphometric information

The genus Melitaea consists of about 80 species, divided into ten species groups, which are all restricted to the Palaearctic region. The Melitaea phoebe group was defined by Higgins based on morphological characters such as wing pattern and genital structures. According to his interpretation, the M. phoebe group included seven species: M. phoebe, M. sibina, M. scotosia, M. aetherie, M. collina, M. consulis and M. turkmanica. The taxonomy of the phoebe species group has been poorly resolved and recent results on the species composition within the group suggest the need for a re‐evaluation. In this study molecular sequences (5985 bp) including one mitochondrial (COI) and up to six nuclear (CAD, EF‐1α, GAPDH, MDH, RpS5 and wingless) gene regions from 38 specimens of the Melitaea phoebe species group sensu Higgins and some closely related taxa from the Palaearctic region were analysed. The possible evolution of the processus posterior of the male genitalia was also reconstructed based on a shape mapping technique. The analysis of the combined data shows a very clear pattern and almost all relationships are highly supported. Based on the combined Bayesian tree and the shape of the processus posterior of the male genitalia, four main groups are recognised: (i) collina group, (ii) arduinna group, (iii) aetherie group and (iv) phoebe group. The status of M. ornata, M. zagrosi and M. scotosia as species is confirmed, and the results also indicate that M. telona (s.s.) from Israel is a separate species.     

Phylogenetic relationships of Acronictinae with discussion of the abdominal courtship brush in Noctuidae (Lepidoptera)

We present results of an eight‐gene molecular study of the subfamily Acronictinae and related Noctuidae. Amphipyrinae are recovered as sister to Acronictinae, but with weak support – not surprisingly, the content of the two subfamilies has often been mixed in classifications. Balsinae, previously placed near Acronictinae or within Noctuinae, is recovered within an unresolved polytomy of Cuculliinae, Eustrotiinae, Raphiinae and Dilobinae. Gerbathodes Warren, Moma Hübner and Nacna Fletcher are excluded from Acronictinae. Three genera recently transferred into the subfamily – Cerma Hübner, Chloronycta Schmidt & Anweiler and Comachara Franclemont – are confirmed as acronictines. Lophonycta Sugi (the type genus of Lophonyctinae) is returned to the Acronictinae. Sinocharis Püngeler, formerly considered to be Acontiinae or as the basis of its own subfamily Sinocharinae, is nested within early diverging Acronictinae genera. Both subfamilies are formally synonymized: i.e. Lophonyctinae syn.n. and Sinocharinae syn.n. Nine acronictine genus‐level taxa were found to nest within the nominate genus Acronicta Ochsenheimer: Eogena Guenée, Hyboma Hübner, Hylonycta Sugi, Jocheaera Hübner, Oxicesta Hübner, Simyra Ochsenheimer, Subacronicta Kozhanchikov, Triaena Hübner, and Viminia Chapman. Eogena, Oxicesta, and Simyra, currently treated as valid genera, nest within terminal clades of the genus Acronicta and are here subsumed within the genus: Eogena syn.n. , Oxicesta syn.n. and Simyra syn.n. Four well‐supported species groups within Acronicta are identified: the alni clade, the leporina clade, the nervosa clade and the psi clade. While many previous treatments have stated explicitly that Acronictinae lack abdominal scent brushes, or excluded genera with brushes from the subfamily, we show that well‐developed brushes are present in three early diverging acronictine genera: Cerma, Lophonycta, and Sinocharis. We illustrate and describe the brushes of all three genera, and briefly review the taxonomic distribution of the anterior abdominal courtship brushes in Noctuidae, emphasizing the labile evolutionary distribution of these structures.