Iridoid biosynthesis in staphylinid rove beetles (Coleoptera: Staphylinidae, Philonthinae)

The biosynthesis of chrysomelidial and plagiodial was studied in the rove beetle subtribe Philonthina (Staphylinidae). Glandular homogenates were found to convert synthetic (2E,6E)-[trideuteromethyl-5,5-(2)H(5)]octa-2,6-diene-1,8-diol (10) into nor-chrysomelidial (14) and nor-plagiodial (13). The overall transformation requires; i) oxidation of the substrate at C(1) and C(8), ii) cyclization of the resulting dialdehyde to nor-plagiodial followed by iii) isomerization to give nor-chrysomelidial. The oxidase requires molecular oxygen as a cofactor and operates with removal of the pro-R hydrogen from C(1) and C(8) of synthetic (1R,8R,2E,6E)-[1,8-(2)H(2)]-2,6-dimethyl-octa-2,6-diene-1,8-diol (15), producing a dialdehyde along with H(2)O(2). Unlike enzymes from iridoid-producing leaf beetle larvae, the Philonthus enzyme is able to oxidize saturated substrates such as citronellol. Crude protein extracts prepared from Philonthus glands by ammonium sulfate precipitation, were found to produce hydrogen peroxide at a rate of 0.085+/-0.003 ng H(2)O(2) (ng protein)(-1) hr(-1) with nerol as an oxidase substrate. The cyclase operates with opposite stereochemistry to the enzyme(s) from Phaedon cochleariae and other herbivorous leaf beetles, specifically removing the C(5)-H(R) hydrogen atom from (4R,5S,2E,6E)-[4,5-(2)H(2)]-2-methyl-octa-2,6-diene-1,8-diol (17). These findings have enabled us to construct a detailed account of iridoid biosynthesis in rove beetles, which resembles the biosynthetic route in leaf beetle larvae, but exhibits distinct stereochemical differences.     

Diagnosis, classification, and phylogenetic relationships of the orphnine scarab beetles (Coleoptera, Scarabaeidae: Orphninae)

Orphnine scarab beetles (Orphninae) are widely distributed in the tropical and subtropical regions of the southern continents except for Australia. The catalogue of nominal taxa of orphnines includes 2 tribes, 15 genera, and 195 species. Diagnosis of the group, based on adult morphological characters, is as follows: antennae 10-segmented with 3-segmented club; mandibles with 2?C4 scissorial teeth and well developed mola; labrum and mandibles protruding past clypeus and visible from above; scutellum well developed in winged species, reduced but distinct in wingless species; wings with distinct anal area; apices of anterior tibia in males without spur but normally with a few robust setae; anterior coxa with longitudinal hollow on anterior surface; tarsi with 2 similar claws; middle and hind tibiae with 2 apical spurs; abdominal sternite 2 with sub-triangular to rounded plectrum; dorsal surface of hind coxae with oval flat stridulatory file; pygidium partly hidden under elytra; parameres symmetrical; bursa copulatrix sacciform, membranous; spermatheca C-shaped, not sclerotized; accessory vaginal glands developed; abdomen with 2 sclerotized tergites (VII?CVIII) and 6 visible sternites (III?CVIII). Preliminary phylogenetic analysis based on 47 characters of adult morphology shows that the tribe Aegidiini Paulian is a natural, monophyletic group. The genus Stenosternus Karsch described from a single specimen from S?o Tomé Island (Gulf of Guinea), is morphologically more similar to the New World taxa than to the Old World ones and is provisionally placed in Aegidiini. The tribe Orphnini Erichson seems non-monophyletic and has no synapomorphies. The genus Orphnus is apparently a polyphyletic group and it needs taxonomic revision. The hypothesis on sister-group relationship of Orphninae and Allidiostomatinae, based on molecular data, is not supported by the morphological characters. The stridulatory organs (the putative synapomorphy of Orphninae + Allidiostomatinae) are not identical in these groups; the mouthparts and female genitalia are essentially different. Orphninae have chewing mouthparts with large scissorial teeth and well developed mola, which is characteristic of generalist saprophagous species. Allidiostomatinae have mandibles with scissorial teeth and mola reduced; they also have sclerotized bursa copulatrix and sclerotized mandibular duct which opens on the dorsal side near condyle. Considering the present day development of alpha-taxonomy of most orphnine taxa, especially the speciose genus Orphnus, it seems premature to propose changes in higher classification of the subfamily. To clarify the phylogenetic position of the Orphninae among scarab beetles it is essential to include representative members of all taxa of orphnine lineage (sensu Browne, Scholtz, 1998) into the analysis.     

Systematics of Cafius corallicola (Fairmaire) (Coleoptera: Staphylinidae) with a discussion of its phylogenetic relationships

A systematic review of the marine littoral Cafius corallicola (Fairmaire), widely distributed along the coasts from the Indian Ocean to the western Atlantic Ocean through the southern Pacific Ocean, is presented based on morphological and molecular characters (COI and 28S). Specimens of the two species [C. corallicola and C. caribeanus Bierig] are extremely similar to each other including the form of the aedeagus. The molecular analyses support the validity of C. corallicola with one synonymy based on morphological characters. Genetic divergence of COI using uncorrected p-distance among these two species ranged from 0.35% to 4.49%. Cafius caribeanus Bierig syn. nov. is synonymized under C. corallicola. Phylogenetic relationships of C. corallicola with similar congeners are resolved as (C. corallicola (C. rufescens (C. filum + C. sericeus))). Cafius corallicola is redescribed with illustrations of diagnostic characters.     

基于触角感器的部分芫菁属、种分类地位和关系分析(鞘翅目:芫菁科)

针对斑芫菁族分类系统中伪斑芫菁属Pseudabris分类关系的不确定,选择该族6个代表种,对其触角感器的形态特征、类型变化和分布位置做了记述、分析比较,提供了扫描电镜照片;基于14个触角特征的分析数据,构建了该族3个属和6个种可能的系统发育树。属间关系:沟芫菁属Hycleus+(伪斑芫菁Pseudabris+苹斑芫菁Mylabris);种间关系:(眼斑沟芫菁H.cichorii+大斑沟芫菁指名亚种H.phaleratus)+((长角伪斑芫菁P.hingstoni+长腹伪斑芫菁P.longiventris)+(苹斑芫菁M.calida+丽斑芫菁M.speciosa))。     

Reproductive Biology of the Andean Shrub Discaria nana (Rhamnaceae)

Abstract: The widely-held view that the frequency of self-compatibility increases at higher elevations has been questioned for communities of the southern Andes. The study of pollination biology of obligate outcrossers with wide altitudinal range may provide clues on how plants can remain reproductively successful in increasingly hostile environments without resorting to selfing. I studied the phenology, pollinator assemblages, breeding system and maternal success of the perennial entomophile outcrosser, Discaria nana, across a 1200-m elevation span in the Andes of Mendoza and Neuquén, Argentina (34° - 37°S). D. nana behaved as self-incompatible throughout the studied gradient. At the higher site proportionally fewer flowers were pollinated, stigmatic loads were smaller and number of visitor species was lower than at low altitude; however, natural fruit set was 3.6 times higher and seed set 3.3 times higher. As a non-exclusive explanation, it is proposed that increased maternal success reflected better pollination quality at the higher site, to which several factors seemed to contribute. At higher altitude D. nana a) exhibited mutualisms with a high proportion of the available pollen vectors, b) had a higher rate of specialized pollinators (Lepidoptera, obligate nectar feeders) to unspecialized ones (Diptera, pollen and mixed feeders) in the visitor assemblage which would reduce ineffective (i.e. self) pollination because nectar feeders visited both male and female phase flowers and pollen feeders favoured male phase flowers, c) had an extended floral longevity (especially the female phase), and d) showed an increased floral display (as number of flowers per unit plant area). Differential rewarding through more concentrated nectar may explain the change in assemblage composition. The flowers' reverse herkogamy (i.e. the location of the stigma below the anthers) seemed to enhance the beneficial effects of the abundance of more effective pollinators.     

The phylogenetic relationships of Chalcosiinae (Lepidoptera, Zygaenoidea, Zygaenidae)

The chalcosiine zygaenid moths constitute one of the most striking groups within the lower-ditrysian Lepidoptera, with highly diverse mimetic patterns, chemical defence systems, scent organs, copulatory mechanisms, hostplant utilization and diapause biology, plus a very disjunctive biogeographical pattern. In this paper we focus on the genus-level phylogenetics of this subfamily. A cladistic study was performed using 414 morphological and biochemical characters obtained from 411 species belonging to 186 species-groups of 73 genera plus 21 outgroups. Phylogenetic analysis using maximum parsimony leads to the following conclusions: (1) neither the current concept of Zygaenidae nor that of Chalcosiinae is monophyletic; (2) the previously proposed sister-group relationship of Zygaeninae + Chalcosiinae is rejected in favour of the relationship (Zygaeninae + ((Callizygaeninae + Cleoda ) + ( Heteropan + Chalcosiinae))); (3) except for the monobasic Aglaopini, none of the tribes sensu Alberti (1954 ) is monophyletic; (4) chalcosiine synapomorphies include structures of the chemical defence system, scent organs of adults and of the apodemal system of the male genitalia. A paired metathoracic androconial organ and a series of abdominal tergal corematal organs have been discovered, both being new to Lepidoptera. Due to highly homoplastic patterns in copulatory structures and wings that demonstrate significant sexual dimorphism, polymorphism and mimicry, 17 of the 69 'true' chalcosiine genera ( c . 25%) are shown to be either paraphyletic or polyphyletic. The present classification is therefore very misleading. Reductions of various parts of the male genitalia in some groups are accompanied by morphological and functional replacement involving the 8th abdominal segment. A prominent but convergent lock and key mechanism is revealed.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 161–341.     

On the phylogenetic relationships of trogons (Aves, Trogonidae)

Although trogons (Aves, Trogonidae) are well characterized by the possession of heterodactyl feet, their phylogenetic relationships to other extant birds still are only poorly understood. Molecular studies did not show conclusive results and there are amazingly few comparative studies of the anatomy of trogons. Virtually the only hypothesis on trogon relationships that was supported with derived morphological characters is a sister group relationship to alcediniform birds (bee-eaters, kingfishers, and allies), which share a derived morphology of the columella (ear-ossicle) with trogons. However, in this study a very similar columella is reported for the oilbird (Steatornithidae) and additional previously unrecognized derived osteological characters are presented, which are shared by trogons and oilbirds. A numerical cladistic analysis of 28 morphological characters also resulted in monophyly of Trogonidae and Steatornithidae, although the corresponding node was not retained in a bootstrap analysis.     

Morphological review ofPelvetia andSilvetia (Fucaceae, Phaeophyta) with an emphasis on phylogenetic relationships

We compared the morphology of all four members ofPelvetia andSilvetia (Fucaceae, Phaeophyta), with an emphasis on phylogenetic relationships.Silvetia is segregated fromPelvetia because it has two, longitudinally divided eggs in the oogonium. In contrast, the eggs of the genusPelvetia are transversally divided. A cladistic analysis, based on 17 morphological features, shows thatPelvetia is closely related toHesperophycus andPelvetiopsis, as are three species ofSilvetia. We can infer from the cladistic tree and biogeographic information that some silvetian ancestor populations from the northern Pacific region likely evolved toS. babingtonii in northern Japan and then moved to Korea and California (USA), whereS. siliquosa andS. compressa, respectively, diverged. Our morphological study corroborates the DNA-based phytogeny and the ensuing taxonomy for the two genera. These results demonstrate the necessity for systematically revising the family Fucaceae to emphasize egg development, rather than egg number, in the oogonium, as a diagnostic character.     

Species boundaries,phylogenetic relationships,and ecological differentiation inAnthriscus (Apiaceae)

Species boundaries and phylogenetic relationships of 17 taxa ofAnthriscus (Apiaceae), with special emphasis on the critical sect.Cacosciadium, were explored using morphological data with principal component analysis, phenetics, and phylogenetics. The analyses did not provide satisfactory resolution of taxa from sect.Cacosciadium and only four species were retained. The total number of species was reduced to nine. Sect.Cacosciadium is distinguished by only two synapomorphies while sects.Anthriscus andCaroides are better supported. Present geographic and ecological variation suggests that the radiation ofAnthriscus occurred through divergence of peripheral isolated populations adapting to different habitats: high montane meadows and screes, shady climax forests, and seasonally dry habitats at lower altitudes. The adaptive significance of particular morphological traits is discussed.     

Erosion of a pollination mutualism along an environmental gradient in a south Andean treelet,Embothrium coccineum (Proteaceae)

The limit of a species’ distribution can be determined biotically if an environmental gradient causes the loss of critical mutualists such as pollinators. We assessed this hypothesis for Embothrium coccineum, a self‐incompatible red‐flowered treelet growing along a strong west‐east precipitation gradient from rainforest to forest‐steppe ecotone in the rain shadow of the southern Andes in northwestern Patagonia. For 16 populations along this gradient, we quantified composition of the pollinator assemblage, pollination efficiency and limitation, and reproductive output. The treelet has a generalized pollination system, but the hummingbird Sephanoides sephaniodes was the most effective pollinator. The relative importance of this hummingbird as a flower visitor within populations influenced pollen transfer and fruit set more strongly than local precipitation. As hummingbirds and other pollinators, including passerine birds and nemestrinid flies, were replaced by bees towards the dry eastern range limit, pollen limitation increased and reproduction eventually failed. These results support the hypothesis that pollinators can act as important biotic filters influencing plant distribution, and warn against predictions of geographical range shifts based solely on climatic variables.     

Species delimitation in the Aleochara fucicola species complex (Coleoptera: Staphylinidae: Aleocharinae) and its phylogenetic relationships

To assess the accuracy of species delimitation and phylogenetic relationships of the Aleochara fucicola species complex, we performed molecular phylogenetic analyses. Detailed micromorphological characters were also examined using scanning electron microscopy (SEM). The molecular data set included two mitochondrial (COI and COII) and three nuclear protein‐coding genes (CAD, EF1‐α and wg) for 19 populations of five species. Significant discordance was found between mitochondrial and nuclear gene trees. Two species, A. puetzi (Assing) and A. segregata Yamamoto and Maruyama, were not separated in the mitochondrial gene trees, but clearly were differentiated in the nuclear and concatenated gene trees. The SEM data also supported the separation of these two species, but an analysis of genetic divergence data did not. Adaptation to extremely harsh environments might reduce morphological variation in the A. fucicola species complex during the colonization of seashores. We present a multilocus phylogeny of the species complex. It suggests that the ancestor of the A. fucicola species complex occurred along the southern coasts of Northeast Asia, followed by dispersals to northern coasts.     

ADH and phylogenetic relationships ofDrosophila lebanonensis (Scaptodrosophila)

Summary Increasing data onDrosophila alcohol dehydrogenase (ADH) sequences have made it possible to calculate the rate of amino acid replacement per year, which is 1.7×10^–9. This value makes this protein suitable for reconstructing phylogenetic relationships within the genus for those species for which no molecular data are available such asScaptodrosophila. The amino acid sequence ofDrosophila lebanonensis is compared to all of the already knownDrosophila ADHs, stressing the unique characteristic features of this protein such as the conservation of an initiating methionine at the N-terminus, the unique replacement of a glycine by an alanine at a very conserved position in the NAD domain of all dehydrogenases, the lack of a slowmigrating peptide, and the total conservation of the maximally hydrophilic peptide. The functional significance of these features is discussed.Although the percent amino acid identity of the ADH molecule inDrosophila decreases as the number of sequences compared increases, the conservation of residue type in terms of size and hydrophobocity for the ADH molecule is shown to be very high throughout the genusDrosophila. The distance matrix and parsimony methods used to establish the phylogenetic relationships ofD. lebanonensis show that the three subgenera,Scaptodrosophila, Drosophila, andSophophora separated at approximately the same time.     

The male postabdomen of the "ancestral" archostematan beetle Tetraphalerus bruchi Heller, 1913 (Ommatidae) and its phylogenetic significance

External and internal features of the male postabdomen of Tetraphalerus bruchi were examined with a broad spectrum of morphological techniques and are described in detail. The conditions found in males of Tetraphalerus are compared to those in other archostematan beetles and members of other coleopteran suborders. The far-reaching reduction of the sternite I, structural modifications of sternite II, the retracted condition of the terminal segments, and ventromedially fused apodemes arising from the anterior margin of tergite IX are likely autapomorphies of Coleoptera. The male postabdomen of Tetraphalerus is less derived than in most other groups of Coleoptera. The sclerotized elements are symmetrical. In contrast to earlier statements on the archostematan male genital apparatus a distinctly developed, sclerotized basal piece is present. The aedeagus is trilobed and all elements of the copulatory apparatus are distinct. The muscular equipment is simple and moderately developed. All muscles (except the transverse muscles 61 and 62) occur pairwise and symmetrically. The distinct increase of the number of postabdominal muscles in representatives of the higher lineages of Coleoptera is likely linked with a torsion of the copulatory apparatus, which also results in asymmetries of the sclerotised parts. The testes of Tetraphalerus are long, multi-coiled tubes like in other archostematans, Myxophaga (Torridincola) and Adephaga. The presence of a deep notch on the parameres is a synapomorphy of Tetraphalerus and Omma. Curved parameres, a shortened distal portion, and a distinctly shortened penis are potential synapomorphies of Omma rutherfordi and Omma mastersi. The large size of the sclerotized part of the phallobase ('basal piece') and the division of the sclerotization of sternum IX are potential ground-plan autapomorphies of Archostemata, with secondary modification of the latter feature in Cupedidae. The reduced condition of the sclerotization of sternum VIII is an apomorphic condition which has likely evolved independently in Tetraphalerus and Paracupes. Further anatomical investigation of the male genital apparatus of Coleoptera and holometabolous insects in general is required for a reliable morphological and phylogenetic interpretation. Concerning the presence or absence of particular sclerotizations (e.g., 'basal piece' of phallobase) histological section series and Confocal Laser Scanning Microscopy can add more precise information to what can be observed using permanent preparations of macerated specimens.