Cladistic analysis, phylogeny and biogeography of the Hawaiian Platynini (Coleoptera: Carabidae)

The 128 known native Hawaiian species of the tribe Platynini are analysed cladistically. Cladistic analysis is based on 206 unit-coded morphological characters, and also includes forty-one outgroup taxa from around the Pacific Rim. Strict consensus of the multiple equally parsimonious cladograms supports the monophyly of the entire species swarm. The closest outgroup appears to be the south-east Asian-Pacific genus Lorostema Motschulsky, whose species are distributed from India and Sri Lanka to Tahiti, supporting derivation of the Hawaiian platynines from a source in the western or south-western Pacific. The biogeographic relationships of the Hawaiian taxa are analysed using tree mapping, wherein items of error are minimized. The area cladogram found to be most congruent with the phylogenetic relationships, and most defensible based on underlying character data is {Kauai[Oahu(Hawaii{Lanai[East Maui(West Maui + Molokai)]})]}. This progressive vicariant pattern incorporates progressive colonization from Kauai, and vicariance of the former Maui Nui into the present islands of Molokai, Lanai, West Maui and East Maui. The evolution of flightlessness, tarsal structure, pronotal setation and bursal asymmetry are evaluated in the context of the cladogram. Brachyptery is a derived condition for which reversal is not mandated by the cladogram, although repeated evolution of reduced flight wings is required. Tarsal structure supports Sharp's (1903) recognition of Division 1 as a monophyletic assemblage, but exposes his Division 2 as a paraphyletic group requiring removal of the genus Colpocaccus Sharp. Pronotal setation is exceedingly homoplastic, and is not useful for delimiting natural groups. Left-right asymmetry of the bursa copulatrix reversed twice independently, resulting in mirror-image bursal configurations in B. rupicola and Prodisenochus terebratus of East Maui. The amount of character divergence is greater among species comprising Division 1 than among species of its sister group, the redefined Division 2. Based on superior fit of Division 1 relationships to the general biogeographic pattern, a greater speciation rate coupled with more extensive extinction is rejected as the cause for this greater divergence. Intrinsic differentiation in the processes underlying cuticular evolution appears to be more consistent with the observed biogeographic and morphological patterns.     

Inhibition of tumour and non-tumour cell proliferation by pygidial gland secretions of four ground beetle species (Coleoptera: Carabidae)

Inhibition of the proliferation of human tumour cells and porcine non-tumour cells by the pygidial gland secretion released by adults of four ground beetle species was observed in this study. The sulphorhodamine B (SRB) assay was applied to establish the percentages of inhibition of the net growth of four human tumour cell lines and porcine liver primary non-tumour cells. The secretions of all tested ground beetle species were shown to have an antiproliferative effect on the tested cell lines. Special emphasis is put on the secretion of Abax parallelepipedus, which showed the highest antitumour potential and weakest inhibition of non-tumour cell proliferation. The antitumour and antiproliferative potential of the pygidial gland secretions of ground beetles is here demonstrated for the first time. It is suggested that certain organic acids are responsible for the action. Further investigation needs to be conducted in order to better understand the mechanisms governing the observed cytotoxic and antitumour activity.     

Relative Importance of Sex,Pre-Starvation Body Mass and Structural Body Size in the Determination of Exceptional Starvation Resistance of Anchomenus dorsalis (Coleoptera: Carabidae)

In nature, almost all animals have to cope with periods of food shortage during their lifetimes. Starvation risks are especially high for carnivorous predatory species, which often experience long intervals between stochastic prey capturing events. A laboratory experiment using the common predatory carabid beetle Anchomenus dorsalis revealed an exceptional level of starvation resistance in this species: males survived up to 137 days and females up to 218 days without food at 20°C. Individual starvation resistance was strongly positively affected by pre-starvation body mass but only slightly by beetle structural body size per se. Females outperformed males even when the effect of gender was corrected for the effects of structural body size and pre-starvation body mass. The better performance of females compared to males and of beetles with higher relative pre-starvation body mass could be linked to higher fat content and lean dry mass before starvation, followed by a greater decrease in both during starvation. There was also a difference between the sexes in the extent of body mass changes both during ad libitum feeding and following starvation; the body masses of females fluctuated more compared to males. This study stresses the need to distinguish between body mass and structural body size when investigating the ecological and evolutionary consequences of body size. Investigation of the net effects of body size and sex is necessary to disentangle the causes of differences in individual performances in studies of species with significant sexual size dimorphism.     

大蒜化学成分的气-质联用分析

本文采用环己烷、乙酸乙酯和正丁醇对大蒜（Allium sativum L.）新鲜鳞茎的95%乙醇提取物进行萃取,并与水蒸气蒸馏法提取的挥发油成分进行比较,用GC-MS对其成分进行定性和定量分析.在环己烷萃取物中共检出112个成分,鉴定了38个化合物,占环己烷萃取物总量的80.08%;在乙酸乙酯萃取物中检出86个成分,鉴定了26个化合物,占乙酸乙酯萃取物总量的56.70%;在正丁醇萃取物中未检出挥发性成分.在水蒸气蒸馏法提取的挥发油中共检出109个成分,鉴定了29个化合物,占挥发油总量的83.58%.大蒜95%乙醇提取物的环己烷和乙酸乙酯萃取物及大蒜挥发油中皆以含硫化合物为主.在环己烷和乙酸乙酯萃取物中,阿霍烯的含量分别为生药的0.00395%和0.00145%,大蒜中阿霍烯含量达0.00540%.     

Size and taxonomic constraints determine the seed preferences of Carabidae (Coleoptera)

Several species of carabid beetles are important postdispersal predators of the seeds of herbaceous plants. The preferences of carabids for particular seeds differ, but the factors that determine their choice are little studied. We tested the hypothesis that preferences are determined by taxonomic constraints (carabid species affiliation), and carabid and seed size. The preferences were determined for adults of 30 species of central European field carabids mainly belonging to the tribes Zabrini (17 species) and Harpalini (10 species) (body mass 1–36 mg). In a cafeteria experiment the beetles were offered an excess of seeds from 28 species of dicotyledoneous herbaceous plants (mass 0.1–8.7 mg). The number of seeds eaten during a 5-day experiment was used as an estimate of preference. Mass of the preferred species of seed eaten was positively related to carabid body mass in both tribes. Multivariate analysis indicated three groups of carabid species with marked preferences for particular species of seeds: (i) species of Harpalini favoured mainly the seed of Cirsium arvense and Viola arvensis, (ii) some species of Zabrini the seeds of Asteraceae (Taraxacum officinale, Tripleurospermum inodorum and Crepis biennis) and (iii) other species of Zabrini the small seeds of Brassicaceae and Caryophyllaceae. The species of Harpalini were more generalist and accepted a greater proportion of seed species than Zabrini of the same size. Preferences of carabid seed predators were thus determined by taxonomic and size constraints, as in other groups of predators.     

The pygidial defense gland system of the Steninae (Coleoptera,Staphylinidae): Morphology,ultrastructure and evolution

The pygidial defense glands of the Steninae consist of two big (r1) and two smaller (r2) secretion filled sac-like reservoirs with associated secretory tissues and basal eversible membrane structures. The secretion is made up of deterrent and antimicrobial alkaloids stored in r1 as well as terpenes in r2. The gland cells filling r1 form a band shaped secretory tissue (g1) in an invagination of the reservoir membrane. The content of r2 is secreted by a tissue (g2) surrounding the efferent duct of r1 opposite to r2. In both gland tissues the secretion is produced in type IIIt gland cells and accumulates in an extracellular cavity surrounded by numerous microvilli of the gland cell membrane. After exocytosis the secretion enters an epicuticular duct and is transported to the corresponding reservoir via a conducting canal enclosed in at least one canal cell. While the structure of g1 is very similar in all species of the Steninae, g2 is often reduced. This reduction of the system r2/g2 is accompanied by a decreasing amount of terpenes in the total secretion and could be of interest for phylogenetic studies in the subfamily of the Steninae.     

Identification of pheromone candidates for the eucalyptus weevil,Gonipterus platensis (Coleoptera,Curculionidae)

The eucalyptus weevil, Gonipterus platensis (Coleoptera, Curculionidae), is a major pest of eucalyptus plantations worldwide. To date, no pheromones have been identified for this species, despite their valuable potential as tools in monitoring or control strategies. Here we report the detection and identification of pheromones candidates of G. platensis. The weevil's volatile compounds were collected by solid phase micro extraction (SPME) and monolithic material sorption extraction (MMSE). Using Gas Chromatography coupled to Mass Spectrometry (GC/MS) analysis, eleven insect specific compounds were detected and identified: verbenene, cis-verbenol, trans-verbenol, verbenone, 2-oxo-1,8-cineole, 9-hydroxy-1,8-cineole, 2-α-hydroxy-1,8-cineole, 3-oxo-1,8-cineole, 2-β-hydroxy-1,8-cineole, 3-α-hydroxy-1,8-cineole and 7-hydroxy-1,8-cineole. Three of these compounds, verbenene, cis-verbenol and trans-verbenol, were shown to be male-specific. Antennal sensitivity towards ten compounds emitted by G. platensis was detected using Gas Chromatography–Mass Spectrometry/Electroantennographic Detection (GC-MS/EAD). Extracts from virgin males proved to be attractive to virgin females in olfactometer bioassays. Further behavioural bioassays showed that both virgin females and virgin males were attracted to the male-specific compound cis-verbenol and that virgin females were attracted to trans-verbenol. Verbenone was attractive to mated females. Regarding 2-α-hydroxy-1.8-cineole and 2-oxo-1,8-cineole, which are produced by both sexes, the alcohol was attractive to virgin males and both the alcohol and the ketone were repellant to mated females. This is, to our knowledge, the first identification of pheromones candidates in Gonipterus spp. and also the first evidence of cineole metabolites acting as semiochemicals.     

A remarkably modified species of the tribe Platynini (Coleoptera,Carabidae) from a limestone cave in Jiangxi Province,eastern China

Morimotoidius zhushandong sp. n. is described and illustrated from a limestone cave called Zhushan Dong II in Wanzhai Xian (=County) of western Jiangxi Province, eastern China. This species is the most modified species within the tribe Platynini in China by having very slender body and appendages, extremely elongated head, and especially, narrowed and barrel-liked pronotum which is as wide as head. However, the above derived characters are autapomorphies to adapt the subterranean environment. M. zhushandong sp. n. must be a troglobite though it has well pigmented body and flat eyes.     

Hybridization and speciation in the carabid beetles of the subgenusOhomopterus (Coleoptera, Carabidae, genusCarabus)

Natural hybridization among wingless carabid beetles of the subgenusOhomopterus (Carabidae, genusCarabus) is reviewed, and its significance in the evolution of this subgenus discussed. Natural hybridization occurs between parapatric species of similar size. Two case studies of natural hybridization suggest that natural hybridization could have affected the evolution of this subgenus in different ways. When there is a large difference in genital morphology between hybridizing species, interspecific copulation often results in genital injuries that causes mortality of copulating individuals, and hence reduces the fitness of hybridizing individuals greatly. In such a case, hybridization may be effective in maintaining the parapatric distribution of the two species, and in the long term, may promote reinforcement selection for traits which are effective in prezygotic reproductive isolation. When the morphological difference in genitalia is not so large as to cause genital injury, a hybrid population may be established at the intermediate zone between two parental species, provided that the immigration rates of the two species into the intermediate zone are small. Thus, natural hybridization may have contributed to both divergence and reticulate evolution in this subgenus.     

Low intensity surface fire instigates movement by adults of Calosoma frigidum (Coleoptera, Carabidae)

The genus Calosoma (Coleoptera: Carabidae) is a group of large, sometimes ornate beetles, which often voraciously attack caterpillars. Many studies have reported Calosoma beetles being highly conspicuous during defoliator outbreaks. Based on observations of individual beetle behavior, patterns of activity density and phenology we provide a hypothesis on how environmental cues may synchronize Calosoma activity with periods of high defoliation. We have observed that adults of Calosoma frigidum construct underground burrows similar to those reported to be created by larvae for pupation. We propose that small increases in soil surface temperature caused either by defoliation events or decreased albedo of blackened, burned soil causes beetles to leave their underground burrows and begin foraging. Indirect support for this hypothesis comes from high levels of adult Calosoma frigidum collected in relatively small patches of burned forest (<200m(2)) relative to the surrounding mosaic of unburned forest shortly after a prescribed surface burn.     

Four new species of the Australian Pamborus Latreille (Coleoptera, Carabidae) carabid beetles

Abstract  Based on an examination of the type specimens of all the known species of the genus Pamborus Latrielle (Coleoptera, Carabidae) four new Australian species are recognised and are described as: P. euopacus sp. n., P. moorei sp. n., P. monteithi sp. n and P. cooloolensis sp. n. In addition, Pamborus viridis Gory, P. opacus Géhin and P. subtropicus Darlington are also redescribed based on the type material and lectotypes are designated for the first two species.     

Larval and adult seed consumption affected by the degree of food specialization in Amara (Coleoptera: Carabidae)

Many carabid beetles (Coleoptera: Carabidae) are known to feed on plant seeds, but the level of specialization on this food differs. This is the first study in which seed consumption is assessed for all larval instars and adults of ground beetles. Three species of Amara with syntopic occurrence, Amara aenea (DeGeer), Amara familiaris (Duftschmid) and Amara similata (Gyllenhal), were examined. Larvae of all three instars and adults were fed seeds of Stellaria media (L.) Vill., Capsella bursa‐pastoris (L.) Med. and Taraxacum officinale Wick. ex Wigg. in a laboratory no‐choice experiment. In general, larvae, particularly the first instar, showed greater differences in seed consumption than the adults, although the latter showed similar but less marked pattern. Amara aenea consumed all offered seed diets in all life stages. All three larval instars of granivorous A. familiaris almost exclusively fed on seeds of S. media and the adults also ate significantly more of this than other seeds. Amara similata consumed mostly seeds of C. bursa‐pastoris in the first instar and adult stages, whereas the larvae of the later instars seemed to be unspecialized on particular seed diet. Differences in seed‐specific consumption between larval instars in granivorous carabids are reported for the first time. The results provide further support for the parallel evolution of various degrees of granivory in the genus Amara, which may ultimately facilitate species coexistence. The daily seed consumption by the larvae was comparable or (in case of the third instar) even higher than that by the adults. Hence, we suggest that larvae may be the important consumers of seed in the field and should not be forgotten when seed predation is assessed.     

Mandibles and labrum-epipharynx of tiger beetles: basic structure and evolution (Coleoptera, Carabidae, Cicindelitae)

Using for comparison with, and as outgroups for, supertribe Cicindelitae, we describe and illustrate the mandibles and labrum-epipharynx of the basal geadephagans Trachypachus gibbsii LeConte, 1861 (family Trachypachidae), and family Carabidae: Pelophila rudis (LeConte, 1863) (supertribe Nebriitae, tribe Pelophilini) and Ceroglossus chilensis (Eschscholtz, 1829) (supertribe Carabitae, tribe Ceroglossini). The range and pattern of variation in structure of mandibles and labrum-epipharynx within the supertribe Cicindelitae was assessed using scanning-electron (SEM) images of these structures in nine exemplar taxa: Amblycheila baroni (Rivers, 1890), Omus californicus (Eschscholtz, 1829) and Picnochile fallaciosa (Chevrolat, 1854) (representing the Amblycheilini); Manticora tuberculata (DeGeer, 1778) (representing the Manticorini): Tetracha carolina (Linnaeus, 1767) (representing the Megacephalini); Pogonostoma chalybeum (Klug, 1835) (representing the Collyridini); and Therates basalis Dejean, 1826, Oxycheila species, and Cicindela longilabris Say, 1824 (representing the Cicindelini). An evolutionary transformation series was postulated for the mandibles and labrum-epipharynx, based on a reconstructed phylogenetic sequence, which, in turn, was based on morphological and DNAevidence.Principal features of the transformation series for the mandibles included development of a densely setose basal face; wide quadridentate retinaculum; a lengthened incisor tooth; a multidentate terebra (one to five teeth; two-three most frequent), followed by subsequent loss of one or more such teeth; development of a diastema in the occlusal surface; development and subsequent loss of scrobal setae, and reduction and loss of the scrobe. Principal features of the transformation series for the labrum included evolution of form from transverse, sub-rectangular to elongate almost square, to triangular; position and number of setae evolved from dorsal to insertion on the apical margin, the number increased from 8-10 to as many as 36, and decreased to as few as four. The epipharynx broadened evolutionarily, the pedium evolving in form from narrow, triangular and nearly flat, to broad, palatiform, and markedly convex; anterior parapedial setae both increased and decreased in number, and in orientation, from a row parallel to the parapedial ridge to a setal row extended forward at about a right angle to the latter.     

The effects of habitat,density, gender and duration on overwintering success in Bembidion lampros (Coleoptera: Carabidae)

In temperate climates, winter mortality is a key factor influencing insect survival. In Bembidion lampros (Coleoptera: Carabidae), an abundant polyphagous predator in arable farmland, we investigated how habitat, population density, gender and duration of overwintering affect the winter mortality and body condition of survivors. In a field experiment, we introduced beetles at two population densities into isolators placed either in the interior of the field or in the grassy boundary. Half of the isolators were collected in mid‐March, and the remaining half were collected in mid‐April. Across all treatments, 44–92% of the beetles survived until spring. Survival was significantly higher in the field interior than in the boundary. The longevity of individuals starved after overwintering was higher in females than in males and was positively related to the length of time spent at the overwintering site. Population density was positively related to percentage survival but did not affect body condition. Our results suggest that biotic factors such as population density and predation, though little studied, may have a similar significance as abiotic factors. Even ubiquitous carabid species inhabiting agroecosystems have specific requirements for overwintering. Understanding these requirements is useful for developing techniques to support their overwintering success.     

Habitat use and seed removal by invasive rats (Rattus rattus) in disturbed and undisturbed rain forest,Puerto Rico

Despite frequent occurrences of invasive rats (Rattus spp.) on islands, their known effects on forests are limited. Where invasive rats have been studied, they generally have significant negative impacts on native plants, birds, and other animals. This study aimed to determine invasive rat distribution and effects on native plant populations via short‐term seed removal trials in tropical rain forest habitats in the Luquillo Experimental Forest, Puerto Rico. To address the first objective, we used tracking tunnels (inked and baited cards inside tunnels enabling animal visitors’ footprints to be identified) placed on the ground and in the lower canopy within disturbed (treefall gaps, hurricane plots, stream edges) and undisturbed (continuous forest) habitats. We found that rats are present in all habitats tested. Secondly, we compared seed removal of four native tree species (Guarea guidonia, Buchenavia capitata, Tetragastris balsamifera, and Prestoea acuminata) between vertebrate‐excluded and free‐access treatments in the same disturbed and undisturbed habitats. Trail cameras were used to identify animals responsible for seed contact and removal. Black rats (Rattus rattus) were responsible for 65.1% of the interactions with seeds, of which 28.6% were confirmed seed removals. Two plant species had significantly more seeds removed in disturbed (gaps) than undisturbed forest. Prestoea acuminata had the lowest seed removal (9% in 10 days), whereas all other species had >30% removal. Black rats are likely influencing fates of seeds on the forest floor, and possibly forest community composition, through dispersal or predation. Further understanding of rat–plant interactions may be useful for formulating conservation strategies.     

Identification by GC-EAD of the two-component trail-following pheromone of Prorhinotermes simplex (Isoptera, Rhinotermitidae, Prorhinotermitinae)

GC/MS analysis confirmed that neocembrene is the major component of the trail pheromone in the three species of the termite genus Prorhinotermes (P. simplex, P. canalifrons, P. inopinatus). In addition, EAG and GC-EAD experiments with P. simplex strongly suggest that dodecatrienol is a quantitatively minor component but a qualitatively important component of this trail pheromone. Trail-following bioassays confirmed the two-component nature of the trail pheromone. This is the first report of the use of the GC-EAD for the identification of trail pheromone in termites. These original results underline once again the special phylogenetic status of the Prorhinotermitinae among Rhinotermitidae.     

Compounds released by disturbed adults of the haematophagous bug Triatoma infestans (Hemiptera: Reduviidae): behavioural effects of single compounds and binary mixtures

Adults of the Chagas disease vector Triatoma infestans Klug (Hemiptera: Reduviidae: Triatominae), possess paired exocrine glands: the metasternal and Brindley's glands. Both glands are discharged by disturbed adults, releasing an alarm pheromone that elicits an escape response of larvae. The present study analyzes the individual (or combined) effects of some of the volatiles of the whole pheromone blend released under disturbance, searching for active compounds and for possible interactions (e.g. synergism, additive effects) between them. Using an experimental arena, different doses of components emitted by disturbed adults are tested against larvae. Larvae show escape responses to some of the acids, as well as to one alcohol, but no response to ketones. This is observed with certain doses of compounds from Brindley's glands (isobutyric, butyric and acetic acid; 2‐methyl‐1‐butanol), although the compounds tested in the present study that are produced by metasternal glands are shown to evoke random responses, suggesting that mainly Brindley's glands are involved in the alarm context. Two combinations of two individually repellent compounds (2‐methyl‐1‐butanol with acetic or isobutyric acid) evoke escape responses, although other combinations make the individual effect disappear. A different mixture of two individually repellent compounds (butyric and isobutyric acid) evokes attraction, although these are also host odours. The potential use of the active compounds released by disturbed adults to monitor triatomine populations is discussed.     

Sensory structures involved in prey detection on the labial palp of the ant‐hunting beetle Siagona europaea Dejean 1826 (Coleoptera,Carabidae)

Giglio, A., Ferrero E.A., Perrotta, E., Talarico, F.F. and Zetto Brandmayr, T. 2010. Sensory structures involved in prey detection on the labial palp of the ant‐hunting beetle Siagona europaea Dejean 1826 (Coleoptera, Carabidae). —Acta Zoologica (Stockholm) 91 : 328–334 The ultrastructure and distribution of sensilla on the labial palps of a myrmecophagous carabid beetle, Siagona europaea, were investigated using scanning and transmission electron microscopy techniques. Five types of sensilla were identified: three types of sensilla basiconica on the apical sensory area and two types, one sensillum trichodeum and one coeloconicum, on the external palp surface. On morphological grounds, the s. basiconica type 1 were considered as olfactory, the type 2 as gustatory, the type 3 and the s. trichodeum as mechanoreceptive, and the s. coeloconicum as a thermo/hygroreceptor. Their function is discussed in relation to prey detection and habitat adaptations.