Electrophysiological Responses of Trissolcus japonicus, T. basalis, and T. oenone (Hymenoptera: Scelionidae) to Volatile Compounds Associated with New Zealand Stink Bugs (Hemiptera: Pentatomidae).

Parasitoid biological control agents rely heavily on olfaction to locate their hosts. Chemical cues associated with hosts and non-hosts are known to influence the expression of host preferences and host-specificity. A better understanding of how and why parasitoids attack some species and not others, based on volatile organic compounds associated with potential hosts, can provide key information on the parasitoid's host preferences, which could be applied to pre-release risk assessments for classical biological control agents.

Juvenile leg autotomy predicts adult male morph in a New Zealand harvestman with weapon polymorphism.

Intraspecific weapon polymorphisms that arise via conditional thresholds may be affected by juvenile experience such as predator encounters, yet this idea has rarely been tested. The New Zealand harvestman has three male morphs: majors (alphas and betas) are large-bodied with large chelicerae used in male-male contests, while minors (gammas) are small-bodied with small chelicerae and scramble to find mates. Individuals use leg autotomy to escape predators and there is no regeneration of the missing leg.

Static allometries do not reflect evolutionary allometry in exaggerated weaponry of male New Zealand sheetweb spiders (Cambridgea spp.).

Across the animal kingdom, exaggerated weaponry is frequently used by one sex to contest access for potential mates. Within species, if disproportionate investment in weaponry confers an advantage to larger individuals, this may result in positive static allometry. It is predicted that the same selective pressures may also lead to positive evolutionary allometry, where larger species bear disproportionately large weapons on average, compared with smaller species.

Camouflage in lichen moths: Field predation experiments and avian vision modelling demonstrate the importance of wing pattern elements and background for survival.

Background matching is perhaps the most ubiquitous form of defensive camouflage in the animal kingdom, an adaptive strategy that relies on the visual resemblance between a prey organism and its background to promote concealment from predators. The importance of background matching has been acknowledged for over a century, yet despite its renown and apparent pervasiveness, few studies exist that have objectively quantified its occurrence and tested the functional significance of background matching in a specific animal study system. The North Island lichen moth Declana atronivea presents a fascinating system to investigate such anti-predator coloration.

Irradiation-induced sterility in an egg parasitoid and possible implications for the use of biological control in insect eradication.

Classical biological control is a pest control tool involving the release of imported natural enemies. The Sterile Insect Technique (SIT) comprises releasing sexually sterile insects of a pest into the wild population for suppression or eradication. Both these approaches are environmentally friendly and their combination can result in a synergistic impact on pest populations and improve eradication.

Male coercion and female injury in a sexually cannibalistic mantis.

Sexual conflict can generate coercive traits in males that enhance mating success at the expense of female fitness. Pre-copulatory sexual cannibalism-where females consume males without mating-typically favours cautious rather than coercive mating tactics, and few examples of the latter are known. Here, we show that males of the highly cannibalistic springbok mantis, , wrestle females during pre-mating interactions.

Cybernetic combatants support the importance of duels in the evolution of extreme weapons.

A current evolutionary hypothesis predicts that the most extreme forms of animal weaponry arise in systems where combatants fight each other one-to-one, in duels. It has also been suggested that arms races in human interstate conflicts are more likely to escalate in cases where there are only two opponents. However, directly testing whether duels matter for weapon investment is difficult in animals and impossible in interstate conflicts.

Mate-finding Allee effects can be exacerbated or relieved by sexual cannibalism.

Allee effects occur when individual or population survival decreases due to populations being small or sparse. A key mechanism underlying Allee effects is difficulty in finding mates at low densities. Species may be particularly vulnerable to mate-finding Allee effects if females rely on an abundance of males to reproduce successfully.

Muscle mass drives cost in sexually selected arthropod weapons.

Sexually selected weapons often function as honest signals of fighting ability. If poor-quality individuals produce high-quality weapons, then receivers should focus on other, more reliable signals. Cost is one way to maintain signal integrity.

Weak premating isolation between Clitarchus stick insect species despite divergent male and female genital morphology.

Documenting natural hybrid systems builds our understanding of mate choice, reproductive isolation and speciation. The stick insect species Clitarchus hookeri and C. tepaki differ in their genital morphology and hybridize along a narrow peninsula in northern New Zealand.

Sexual cannibalism and population viability.

Some behaviours that typically increase fitness at the individual level may reduce population persistence, particularly in the face of environmental changes. Sexual cannibalism is an extreme mating behaviour which typically involves a male being devoured by the female immediately before, during or after copulation, and is widespread amongst predatory invertebrates. Although the individual-level effects of sexual cannibalism are reasonably well understood, very little is known about the population-level effects.

Exaggerated male legs increase mating success by reducing disturbance to females in the cave wētā .

Mate guarding is a widespread behaviour resulting from sperm competition and conflict over optimal remating rates. It is a key way in which males exhibit differential mating investment, and represents a complex interplay between mating effort, intrasexual competition, opportunity costs and sexual conflict. Nevertheless, although there are many examples of exaggerated male structures used to fight rivals, few animals have developed specialized male morphological adaptations for directly sheltering females from disturbance by non-rivals.

Geometric morphometrics and molecular systematics of Xanthocnemis sobrina (McLachlan, 1873) (Odonata: Coenagrionidae) and comparison to its congeners.

The taxonomy of the damselfly genus Xanthocnemis is revised, with particular focus on populations inhabiting the North Island of New Zealand. Earlier studies revealed two species: X. sobrina, restricted to cool, shaded streams in kauri forests and other forested areas, and X.

Multiple exaggerated weapon morphs: a novel form of male polymorphism in harvestmen.

Alternative reproductive tactics in animals are commonly associated with distinct male phenotypes resulting in polymorphism of sexually selected weapons such as horns and spines. Typically, morphs are divided between small (unarmed) and large (armed) males according to one or more developmental thresholds in association with body size. Here, we describe remarkable weapon trimorphism within a single species, where two exaggerated weapon morphs and a third morph with reduced weaponry are present.

The Functional Significance of Chiral Genitalia: Patterns of Asymmetry, Functional Morphology and Mating Success in the Praying Mantis Ciulfina baldersoni.

Genital asymmetry is relatively common and widespread throughout the animal kingdom. The functional significance of genital asymmetry is however, poorly understood for most species. Male praying mantids of the genus Ciulfina are remarkable in possessing complex and directionally asymmetric genital phallomeres in some species, and chirally dimorphic/antisymmetric genitalia in others.

Four new species of Ciulfina Giglio-Tos, 1915 (Mantodea: Liturgusidae, Liturgusinae) from the Northern Territory, Australia .

The praying mantid genus Ciulfina Giglio-Tos includes many small, gracile tree-trunk dwelling species found throughout northern Australia. Four new species of Ciulfina: C. annecharlotteae, C.

Pollinator deception in the orchid mantis.

Mimicry has evolved in contexts such as camouflage, predator deterrence, luring of prey, and pollinator attraction. Mimicry of flowers has until now been demonstrated only in angiosperms, yet it has been hypothesized that the Malaysian orchid mantis Hymenopus coronatus mimics a flower to attract pollinators as prey. Despite the popularity of this charismatic insect, this long-discussed hypothesis has never been experimentally investigated.

Exaggerated trait allometry, compensation and trade-offs in the New Zealand giraffe weevil (Lasiorhynchus barbicornis).

Sexual selection has driven the evolution of exaggerated traits among diverse animal taxa. The production of exaggerated traits can come at a cost to other traits through trade-offs when resources allocated to trait development are limited. Alternatively some traits can be selected for in parallel to support or compensate for the cost of bearing the exaggerated trait.

Fatal attraction: sexually cannibalistic invaders attract naive native mantids.

Overlap in the form of sexual signals such as pheromones raises the possibility of reproductive interference by invasive species on similar, yet naive native species. Here, we test the potential for reproductive interference through heterospecific mate attraction and subsequent predation of males by females of a sexually cannibalistic invasive praying mantis. Miomantis caffra is invasive in New Zealand, where it is widely considered to be displacing the only native mantis species, Orthodera novaezealandiae, and yet mechanisms behind this displacement are unknown.

Different paths to sexual size dimorphism in two praying mantids, Pseudomantis albofimbriata and Hierodula majuscula.

Sexual size dimorphism (SSD) is widespread among diverse animal taxa and has attracted the attention of evolutionary biologists for over a century. SSD is likely to be adaptive and the result of divergent selection on different size optima for males and females, given their different roles in reproduction. The developmental trajectory leading to SSD may help us to understand how selection acts on male and female size.

Ferocious fighting between male grasshoppers.

Contests among individuals over mating opportunities are common across diverse taxa, yet physical conflict is relatively rare. Due to the potentially fatal consequences of physical fighting, most animals employ mechanisms of conflict resolution involving signalling and ritualistic assessment. Here we provide the first evidence of ubiquitous escalated fighting in grasshoppers.

Intraspecific evidence from guppies for correlated patterns of male and female genital trait diversification.

The role of sexual selection in fuelling genital evolution is becoming increasingly apparent from comparative studies revealing interspecific divergence in male genitalia and evolutionary associations between male and female genital traits. Despite this, we know little about intraspecific variance in male genital morphology, or how male and female reproductive traits covary among divergent populations. Here we address both topics using natural populations of the guppy, Poecilia reticulata, a livebearing fish that exhibits divergent patterns of male sexual behaviour among populations.

Chirally dimorphic male genitalia in praying mantids (Ciulfina: Liturgusidae).

Although male polymorphisms occur widely in nature and have received considerable recent attention from studies of alternative mating strategies, male genital polymorphisms are less well known. Here, we describe a dimorphism in the orientation of the male genitalic complex of the praying mantid genus Ciulfina. Populations of Ciulfina species vary in the proportion of males with dextral (right-oriented) and sinistral (left-oriented) genitalia, ranging from directional asymmetry (single orientation only) to apparent antisymmetry (equal proportions of both orientations).

Internal reproductive anatomy of the praying mantid Ciulfina klassi (Mantodea: Liturgusidae).

Using light and scanning electron microscopy, the internal male and female reproductive anatomy of the praying mantid Ciulfina klassi is identified and described. This is the first detailed study to investigate the internal reproductive morphology of any Mantodea. The female structures identified were (1) paired ovaries with primitive panoistic type ovarioles, (2) a single blind-ended spermatheca with secretory gland cells and surrounding layer of striated muscle, and (3) female accessory glands associated with the production of the ootheca (the egg casing).