Comparative Endocrinology of Steroid Hormones in Vertebrates

Recent advances in biochemical techniques have resulted in considerableprogress in the comparative qualitative analysis of non-mammalianvertebrate steroids. The literature surveyed herein suggeststhat a number of C21, C19, and C18 steroids occur throughoutthe subphylum. although there may be important qualitative differenceseven among closely related forms. The potential importance,from a phylogenetic or a physiological standpoint, of new steroidsrecently characterized in fishes cannot be evaluated at present. Three widely used techniques—tissue extraction or incubationwithout added precursors, tissue incubation with exogenous steroidsubstrates, and the histochemical visualisation of 3ßhydroxysteroiddehydrogenases—are discussed, and their application tothe study of steroidogenic tissues is illustrated. The adrenocorticalhomologue (interrenal), the ovary, and the testis appear tofunction as sources of steroid hormones in those vertebrateswhich have been examined. However, the existence of additionalsteroidogenic tissues, or of tissues which may modify the steroidcomposition of the body fluids in other ways, is also suggested.     

Phylogeny and feeding trait evolution of the mega‐diverse Gelechioidea (Lepidoptera: Obtectomera): new insight from 19 nuclear genes

The Gelechioidea (>18 000 species), one of the largest superfamilies of Lepidoptera, are a major element of terrestrial ecosystems and include important pests and biological model species. Despite much recent progress, our understanding of the classification, phylogeny and evolution of Gelechioidea remains limited. Building on recent molecular studies of this superfamily and a recently revised family/subfamily classification, we provide an independent estimate of among‐family relationships, with little overlap in gene sample. We analysed up to five nuclear genes, totalling 6633 bp, for each of 77 gelechioids, plus up to 14 additional genes, for a total of 14 826 bp, in 45 of those taxa and all 19 outgroup taxa. Our maximum‐likelihood (ML) analyses, like those of previous authors, strongly support monophyly for most multiply‐sampled families and subfamilies, but very weakly support most relationships above the family level. Our tree looks superficially divergent from that of the most recent molecular study of gelechioids, but when the previous tree is re‐rooted to accord maximally with ours, the two phylogenies agree entirely on the deepest‐level divergences in Gelechioidea, and strongly though incompletely on among‐family relationships within the major groups. This concordance between independent studies is evidence that the groupings (or at least the unrooted branching order) are probably accurate, despite the low bootstrap values. After re‐rooting, both trees divide the families into three monophyletic groups: a ‘Gelechiid Assemblage,’ consisting of Gelechiidae and Cosmopterigidae; a ‘Scythridid Assemblage,’ consisting of Stathmopodidae, Scythrididae, Blastobasidae, Elachistidae, Momphidae, Coleophoridae and Batrachedridae; and a ‘Depressariid Assemblage,’ consisting of Autostichidae, Xyloryctidae, Lecithoceridae, Oecophoridae, Depressariidae and Lypusidae. Within the largest family, Gelechiidae, our results strongly support the pairing of Anomologinae with Gelechiinae, in accordance with a recent study of this family. Relationships among the other subfamilies, however, conflict moderately to strongly between studies, leaving the intrafamily phylogeny unsettled. Within the ‘Scythridid Assemblage,’ both trees support an ‘SSB clade’ consisting of Blastobasidae + (Scythrididae + Stathmopodidae), strongly resolved only in our results. Coleophoridae + Batrachedridae is supported, albeit weakly, in both trees, and only Momphidae differ in position between studies. Within the ‘Depressariid Assemblage,’ both trees support an ‘AXLO’ clade consisting of Autostichidae, Xyloryctidae, Lecithoceridae and Oecophoridae. The monophyly of this clade and relationships therein are supported weakly in previous results but strongly in ours. The recently re‐defined family Depressariidae is paraphyletic in our tree, but the evidence against depressariid monophyly is very weak. There is moderate support for a core group of Depressariidae consisting, among the seven subfamilies we sampled, of Depressariinae, Aeolanthinae and Hypertrophinae. We show that gelechioids have a higher total number and percentage of species that are saprophagous as larvae than any other apoditrysian superfamily, that saprophagy is concentrated primarily in the ‘AXLO clade,’ and that the ancestral gelechioid condition was probably feeding on live plants. Among the living‐plant feeders, concealed external feeding was probably the ancestral state. The multiple origins of internal feeding of various kinds, including leaf mining (otherwise almost unknown in Apoditrysia), are restricted mostly to the Scythridid and Gelechiid Assemblages. The traits that predispose or permit lineages to adopt these unusual life histories are worthy of study.     

New insights on systematics and phylogenetics of Mediterranean Blaps species (Coleoptera: Tenebrionidae: Blaptini), assessed through morphology and dense taxon sampling

The genus Blaps is an emblematic group of large flightless beetles adapted to semi‐arid and arid environments. About 230 species have been described in the subgenus Blaps, which is the largest of the four extant subgenera. Within this subgenus, one large group of morphologically homogeneous species is of particular interest, and comprises the species formerly assigned to Seidlitz's division one. Strikingly, almost all species in this group are endemic to the Mediterranean basin, whereas the remaining Blaps species are mostly distributed in Asia. Here we present the first phylogenetic hypothesis for the Mediterranean Blaps and several taxonomic clarifications for the North African species belonging to this group. Based on careful examination of almost all type material and thousands of specimens for all known species and subspecies (initially 65 taxa), seven lectotypes are designated and six new synonymies are established: Blaps heydeni Allard, 1880 = Blaps heydenissp. taciturna Peyerimhoff syn.n. , Blaps emondi Solier = Blaps nitidula Solier syn.n. , Blaps tripolitanica Karsch = Blaps vialattei Peyerimhoff syn.n. , Blaps bifurcata strauchi Reiche = Blaps bifurcata ssp. gridellii Pierre syn.n. , Blaps cognata Solier = Blaps schweinfurhtii Seidlitz syn.n. and Blaps judaeorum Miller = Blaps pharao Seidlitz syn.n. Among the examined material, five species are also new for science and are assigned to extant species group. To infer species relationships, a morphological character matrix was assembled and analysed using both parsimony and probabilistic methods. All analyses yielded a similar and repeatable phylogenetic pattern, which allows us to discuss the systematics of the Mediterranean endemic species, the limit of extant species groups and to clarify the taxonomic status of several ambiguous taxa. We also reveal the existence of a large clade that encompasses the eastern Mediterranean species that are also mostly associated with arid regions. This clade is embedded within a second group that corresponds to western Mediterranean species, which are generally found in semi‐arid regions. Finally, we discuss the relevance of species groups in relation to their geographic distribution. This work represents a first step for further studies in taxonomy, systematics and historical biogeography of Blaps species.     

Political and social drivers for access to the countryside: the need for research on birds and recreational disturbance

The introduction of a statutory right of access to open country and registered common land in England and Wales in 2005 was a major milestone in a campaign traceable to the 19th century, with views strongly polarized between social classes and political parties, and between land owners and campaigners. More recently, access has also been recognized as a factor contributing to quality-of-life, public health, social diversity and rural economic issues. The mapping of access land revealed that 55% of it is also designated Site of Special Scientific Interest, where wildlife is legally conserved. This has generated a need to assess the implications of access in each case, and take measures to ensure nationally and internationally important features are protected, drawing on sound scientific principles. Early research, although competently undertaken, often failed to address population-scale effects significant at the designated-site level, enabling disputes and polarized 'beliefs' to be articulated. Hence, in addition to drawing up formal and transparent procedures for evaluating impacts and resolving difficulties, funds were released and a major programme initiated, commissioning applied research of direct relevance to the implementation of the legislation. This has pushed forward the boundaries of knowledge in a field which is both difficult and expensive to study. By gradually replacing 'belief' with evidence, this represents a case study in resolving environmental disputes.     

The biology and host searching behaviour of a Cynipoid parasite of aphidophagous syrphid larvae

Abstract. 1. Callaspidia defonscolombei was found to be a common, solitary, thelytokous parasitoid of aphidophagous syrphid larvae. In 1977 it was bivoltine with adults being most numerous in early August and late September. It is probably polyphagous.
2. An analysis of host searching behaviour suggests that females respond to an aphid odour bringing them to the region of an aphid colony.
3. Syrphid hosts are located within the aphid colony by response to a contact chemical. There is a host size preference, only larger second and third instar larvae being attacked.
4. Females inject a venom, which temporarily paralyses host larvae, and place the egg inside a cerebral ganglion.     

When rare species become endangered: cryptic speciation in myrmecophilous hoverflies

The myrmecophilous hoverfly, Microdon mutabilis, is listed as a ‘Rare’ or ‘Nationally Notable Species’ in UK Red Data Books. As an obligate social parasite, feeding only from ant colonies, its life‐style satisfies theoretical conditions under which cryptic speciation is predicted to evolve; namely, strong selection for nonmorphological adaptations that enhance its exploitation of a local subspecies or populations of its host. Samples of larvae and pupae in Ireland, Scotland and England showed that M. mutabilis exploits a single and different host ant species on different sites across its range. In nine southern English colonies, 95.6% of infested nests were of Myrmica scabrinodis whereas in six Irish and two Scottish colonies 100% and 94.2%, respectively, of the infested nests were of Formica lemani, despite M. scabrinodis being common at all sites. Although the adults from ‘scabrinodis’ (and lemani) populations are cryptic, morphometric measurements of pupae showed consistent diagnostic characters that were sufficiently distinct for these ecotypes to be classed as separate species. We conclude that M. mutabilis is the ‘lemani‐type’ and designate the ‘scabrinodis‐type’ as a new species, Microdon myrmicae spec. nov. Thus, one of the listed threatened species of the British Isles becomes two species, each possessing about half the number of populations and occupying half the range of the original ‘species’. Each also inhabits a different serai stage within grassland or heathland, and will require a different management regime if its declining populations are to be conserved. ‘M. mutabilis’ is reported with other host ant species on the European continent. In the light of our results, these may prove to be additional cryptic species. We suggest that cryptic speciation is apt to evolve in species, such as myrmecophiles, endoparasites and koinobiont parasitoids, whose life‐styles result in strong selection on their physiological or behavioural characters. The implications for Red Data Book classifications and for practical conservation are discussed. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society, 2002, 75 , 291–300.