Incongruence between morphological and molecular markers in the butterfly genus Zizina (Lepidoptera: Lycaenidae) in New Zealand

The butterfly genus Zizina in New Zealand has a complex taxonomic history due to the presence of morphological intermediates between the two species, the endemic Z. oxleyi and the introduced Z. labradus, in a putative hybrid zone on the east coast of the South Island of New Zealand. This makes species identification in the field problematic, particularly as the presence of hybrids has not been confirmed. We address this uncertainty through morphological and molecular analyses. Specimens were collected from a range of locations in New Zealand, as well as from Australia, and measurements were made of male genitalia and ventral wing coloration. Two mitochondrial genes (COI, ND5) and three nuclear gene fragments (28S, ITS2 and wingless) were also sequenced for a selection of individuals, and the presence of Wolbachia species in genomic DNA was tested. The two species were separable in morphological space, although there was some overlap, and the contact zone appeared to be around Kaikoura on the east coast of the South Island. Furthermore, specimens from the putative hybrid zone could be classified as Z. oxleyi using morphological characters individually, but not when these were used in a principal component analysis. Molecular analysis showed that there was a mean sequence divergence of 2.0% between two clades for COI, and 4.1% for ND5, but suggested that the contact zone between them was in the north‐west of the South Island. However, there was only a single clade for each of the three nuclear markers. It is thought that this incongruence between morphological and molecular markers is indicative of hybridization which is more extensive than previously thought. However, the possibility that recent speciation has occurred or is occurring is not ruled out.     

Field mating rate of female meadow grasshoppers, Chorthippus parallelus, estimated from sperm counts

Abstract.  1. Female mating frequency is an important life-history component in many insect species. It has been suggested that its laboratory measurement may frequently represent an overestimation of the natural situation because laboratory females have little opportunity to avoid matings. Here, numbers of sperm stored by field-collected females are investigated in order to address whether this method is suitable for estimating field mating frequencies.
2. Data on sperm numbers stored by females and their estimated age based on mandible abrasion were fitted to a simple mechanistic model to obtain estimates of: (i) remating interval; (ii) ejaculate size, and (iii) the rate of sperm loss from the female sperm store. Females were calculated to remate every 5.9–7.0 days. By contrast, sperm numbers of field-collected females did not exceed ejaculate size, which would have resulted in the false conclusion that females mate only once.
3. In the laboratory, females first mated when aged 4–11 days and remated approximately every 2.6 days. Because females are not restricted by mate encounters under these conditions, this confirms the notion that female mating rates are likely to be lower in the field than in the laboratory. Such reduced field mating rates should be taken into account when predicting ecological or evolutionary parameters based on laboratory observed mating rates.     

Three‐dimensional flight tracking shows how a visual target alters tsetse fly responses to human breath in a wind tunnel

Tsetse flies Glossina spp. (Diptera; Glossinidae) are blood‐feeding vectors of disease that are attracted to vertebrate hosts by odours and visual cues. Studies on how tsetse flies approach visual devices are of fundamental interest because they can help in the development of more efficient control tools. The responses of a forest tsetse fly species Glossina brevipalpis (Newstead) to human breath are tested in a wind tunnel in the presence or absence of a blue sphere as a visual target. The flight responses are video recorded with two motion‐sensitive cameras and characterized in three dimensions. Although flies make meandering upwind flights predominantly in the horizontal plane in the plume of breath alone, upwind flights are highly directed at the visual target presented in the plume of breath. Flies responding to the visual target fly from take‐off within stricter flight limits at lower ground speeds and with a significantly lower variance in flight trajectories in the horizontal plane. Once at the target, flies fly in loops principally in the horizontal plane within 40 cm of the blue sphere before descending in spirals beneath it. Successful field traps designed for G. brevipalpis take into account the strong horizontal component in local search behaviour by this species at objects. The results suggest that trapping devices should also take into account the propensity of G. brevipalpis to descend to the lower parts of visual targets.     

Molecular phylogeny and generic‐level taxonomy of the widespread palaeotropical ‘Heteropsis clade’ (Nymphalidae: Satyrinae: Mycalesina)

The mycalesine butterfly genus Heteropsis Westwood, 1850 (Satyrinae: Mycalesina) has recently been conceived to be represented in three major palaeotropical regions (Madagascar, Africa and Asia), but there has been no formal taxonomic treatment covering this entire group. Studies aimed at understanding the evolutionary success of Mycalesina in the Old World tropics have been hampered by the lack of both a robust phylogeny and a stable nomenclature for this satyrine subtribe. Here, we present a well‐supported molecular phylogeny based on 10 genes and 133 exemplar taxa, representing almost all known species groups of Heteropsis (s.l.), and including all but four known species in Madagascar. We also combine sequences of the exemplars with a morphological matrix of 428 characters. The widespread ‘Heteropsis clade’ is confirmed as monophyletic, but lineages in different geographic regions also form endemic and well‐supported clades with deep divergences among them. Here we establish this group as comprising three genera, Heteropsis (Malagasy region only), Telinga Moore, 1880 (Asia), and Brakefieldia gen.n. (Africa). We recover the genera Telinga and Brakefieldia as sisters with high support. Each genus is taxonomically characterized and a revised synonymic checklist is appended with new combinations and some changes in rank. With a well‐resolved topology and updates to the taxonomy of the group, researchers are now in a position to explore the drivers of the spectacular radiation of the group, notably in Madagascar, where the highest phenotypic and species diversity occurs. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:AAF9F440‐A2D6‐4483‐BF35‐9BC074D9D29B .     

Canopy Closure and Emigration by Juvenile Gopher Frogs

ABSTRACT Although studies have addressed effects of abrupt transitions in habitat type (e.g., forest-clear-cut or forest-field edges) on amphibian movements, little is known about effects of more subtle habitat transitions on patterns of migration and habitat use in amphibians. We used radiotelemetry to study movement patterns of juvenile gopher frogs (Rana capito) emigrating from ponds that were surrounded by longleaf pine (Pinus palustris) forest that varied in structure as a result of fire suppression. Our primary purpose was to determine if frogs emigrate directionally from their natal ponds and select habitat at random during their first month following metamorphosis. We found that frogs emigrated in nonrandom directions from ponds that were surrounded by heterogeneous habitat and selected fire-maintained habitat that was associated with an open canopy, few hardwood trees, small amounts of leaf litter, and large amounts of wiregrass (Aristida beyrichiana). Fire-maintained habitat contained higher densities of burrows excavated by gopher tortoises (Gopherus polyphemus) and small mammals, which are the priamry refuge sites for both juvenile and adult gopher frogs. Frogs moved up to 691 m from their natal ponds, frequently crossed dirt roads, and even seemed to use these roads as migration corridors. To maintain suitable terrestrial habitat for gopher frogs, including habitat used by migrating individuals, it is important to apply frequent prescribed fire to uplands surrounding breeding ponds that lead all the way to the edges of breeding ponds, as well as through ponds during periodic droughts.     

Introducing mother's curse: low male fertility associated with an imported mtDNA haplotype in a captive colony of brown hares

Mitochondrial DNA mutations create variation in the efficiency of the oxidative phosphorylation pathway and therefore cellular energy production. Mildly deleterious mutations may reduce the performance of sperm cells in particular, due to their high energy requirements and low number of mitochondria, yet have little or no effect on the viability of somatic cells or ova. Mutations will be maintained in the population, despite the fitness cost for males, because mtDNA is passed down the female line. We looked for this so-called mother's curse effect in our captive colony of European brown hares. Significantly reduced male reproductive success was detected for a divergent haplotype that could be traced back to hares imported from a remote population. Median reproductive success for these hares was 0.17 compared to 0.49 for the indigenous haplotypes (Wilcoxon rank-sum, P  = 0.002). No difference was detected for female reproductive success, nor were we able to find a nuclear DNA component to variation in male fertility. Our data are strong evidence for a mother's curse effect persisting despite multiple crossings over seven generations. These data raise important issues relating to the reproductive fitness of small or intermixing populations and have particular implications for the management of populations for conservation.     

Ammonite eggs and ammonitellae from the Kimmeridge Clay Formation (Upper Jurassic) of Dorset, England

Eight clusters of small spherical and subspherical objects, some isolated and some associated with shells of perisphinctid ammonites, have been recovered from the Lower and Upper Kimmeridge Clay (Upper Jurassic) of the Dorset coast, England. They have been interpreted as ammonite egg sacs and represent the freshest and best-preserved examples known so far. Their structures and the ecological framework in which they occur are discussed. The parents are thought to be members of the two eudemic genera Aulacostephanus and Pectinatites that dominate the biostratigraphy of the ammonites in the range of the Kimmeridge Clay in which they occur. Isolated nuclei of ammonitellae have also been recovered.