The subgenus Gnypetalia Cameron, 1939 is redefined and raised to the genus rank. Eleven valid species are recognised in the genus, six of which are described as new: Gnypetalia armata sp. n. (Solomon Islands), G. cuccodoroi sp. n. (Philippines: Luzon), G. insularis sp. n. (Solomon Islands), G. luzonica sp. n. (Philippines: Luzon, Palawan), G. nitida sp. n. (Indonesia: Sulawesi) and G. penrisseni sp. n. (Malaysia: Sarawak). One new synonym is established: Gnypetalia parva Cameron, 1950 = Ischnopoda (Caliusa) finitima Pace, 1998 syn. n. Five species are given in new combination: Gnypetalia indica (Cameron, 1939) comb. n (= Gnypeta (Gnypetalia) indica), Gnypetalia parva (Cameron, 1950) comb. n. [= Gnypeta (Gnypetalia) parva], Gnypetalia rougemontiana (Pace, 1986) comb. n [= Tachyusa (Caliusa) rougemontiana], Gnypetalia song (Pace, 1990) comb. n. [= Tachyusa (Caliusa) song] and Gnypetalia thoracica (Fauvel, 1879) comb. n. (= Tachyusa thoracica). Lectotype is designated for Gnypeta indica Cameron, 1939. The taxa are diagnosed, keyed and illustrated. The phylogeny of the aleocharine genus Gnypetalia is analysed using cladistic methods. The monophyly of Gnypetalia is confirmed and three major monophyletic species group are recognised.
The species of flea beetles of the genus Chaetocnema Stephens, 1831 occurring in Madagascar are revised. Four new species (C. cachani, C. hygrophila, C. malgascia and C. orophila) are described and five species (C. bamakoensis Bechyné C. confinis Crotch, C. fuscipennis Scherer, C. ganganensis Bechyné and C. picipes Stephens) are added to the Madagascar fauna. The following new synonymies are proposed: C. wollastoni Baly, 1877 = C. fraterna Harold, 1879 syn. nov. = C. monomorpha Bechyné, 1964 syn. nov.; C. pulla Chapuis, 1879 = C. tantilla Weise, 1910 syn. nov.; C. bilunulata Demaison, 1902 = C. sylvia Bechyné, 1964 syn. nov.; C. vadoni Bechyné, 1948 = C. alaotrensis Bechyné, 1964 syn. nov.; C. gregaria Weise, 1910 = C. insularis Weise, 1910 syn. nov. Lectotypes are designated for C. gregaria Weise, 1910, C. insularis Weise, 1910, C. similis Weise, 1910 and C. tantilla Weise, 1910. A key to all the species is presented. Line drawings of male and female genitalia of all the species are included. Ecological and brief zoogeographical data on some species are given.
The species of Lampetis (Spinthoptera) Casey, 1909 of Central America, North America and the West Indies are revised and 31 species are recognized. Six species from the West Indies [L. aurata (Saunders, 1871), L. aurifera (Olivier, 1790), L. bahamica (Fisher, 1925), L. guildini (Laporte & Gory, 1836), L. straba (Chevrolat, 1867), and L. torquata (Dalman, 1823)], eight species from Mexico [L. auropunctata (Kerremans, 1893) (new record for the USA), L. chalconota (Waterhouse, 1882), L. christophi Théry, 1923, L. dilaticollis (Waterhouse, 1882), L. geniculata (Waterhouse, 1889), L. granulifera (Laporte & Gory, 1837), L. mexicana Théry, 1923, and L. obscura Thomson, 1879], three species from Mexico and Central America [L. cortesi (Laporte & Gory, 1837), L. monilis (Chevrolat, 1834), L. simplex (Waterhouse, 1882)], and three from Central America [L. hirtomaculata (Herbst, 1801) = L. insularis (Casey, 1909) syn. n.; L. lesnei (Kerremans, 1910); and L. srdinkoana (Obenberger, 1924)] are redescribed. Seven new species (L. chamela sp. n., L. colima sp. n., L. cyanitarsis sp. n., L. hondurensis sp. n., L. tigrina sp. n., L. viridicolor sp. n., and L. viridimarginalis sp. n.) are described. Three species from Mexico and the United States [L. cupreopunctata (Schaeffer, 1905), L. drummondi (Laporte & Gory, 1836), and L. webbii (LeConte, 1858)], and one species from Mexico (L. chiapaneca Corona, 2004) are not described here, because they were (re)described recently. The diagnosis, distribution, host plants and phenology data of L. chiapaneca, L. cupreopunctata, L. drummondi, and L. webbii are given. Lampetis famula Chevrolat, 1838 and L. variolosa (Fabricius, 1801) are not recognized herein as Mexican species, because they are from South America according to the literature and specimens studied. Information on variation, distribution, and host plants are given for each species. Photographs of dorsal habitus and male genitalia are included.
1_The young larvae of insects living on dry food produce large amounts of water by the metabolic combustion of dietary lipids. The metabolic production of water needed for larval growth, previously known as hypermetabolic responses to juvenile hormone (JH), is associated with a 10- to 20-fold increase in the rate of O2 consumption (10,000 µl O2/g/h in contrast to the usual rate of 500 µl O2/g/h). Growing and moulting larvae are naturally hypermetabolic due to the endogenous release of JH from the corpora allata. At the last, larval-pupal or larval-adult moult there is no JH and as a consequence the metabolic rate is much lower and the dietary lipid is not metabolized to produce water but stored in the fat body. At this developmental stage, however, a hypermetabolic response can be induced by the exogenous treatment of the last larval instars with a synthetic JH analogue. In D. vulpinus, the JH-treated hypermetabolic larvae survive for several weeks without moulting or pupating. In T. castaneum and G. mellonella, the JH-treated hypermetabolic larvae moult several times but do not pupate. All these larvae consume dry food and the hypermetabolic response to JH is considered to be a secondary feature of a hormone, which is produced by some subordinated endocrine organ., 2_The organ is most probably the controversial prothoracic gland (PG), which is a typical larval endocrine gland that only functions when JH is present. According to our hypothesis, PG activated by JH (not by a hypothetical PTTH) releases an adipokinetic superhormone, which initiates the conversion of dietary lipid into metabolic water. This type of metabolic combustion of dietary lipid produces large quantities of endothermic energy, which is dissipated by the larvae in the form of heat. Thermovision imaging revealed that the body of hypermetabolic larvae of G. mellonella can be as hot as 43°C or more. In contrast, the temperature of "cold" normal last instar larvae did not differ significantly from that of their environment. It is highly likely that thermovision will facilitate the elucidation of the currently poorly understood hormonal mechanisms that initiate the production of metabolic water essential for the survival of insects that live in absolutely dry conditions., Karel Sláma, Jan Lukáš., and Obsahuje seznam literatury
The subgenus Alienosternus Lackner, 2016 of the genus Phoxonotus Marseul, 1862 (Coleoptera: Histeridae), described in Eur. J. Entomol. 113: 240-258, is a junior homonym of Alienosternus Martins, 1976 (Coleoptera: Cerambycidae) and is hereby replaced by Saprinosternus nom. n. The status of the single known type specimens of Phoxonotus suturalis Lewis, 1907, P. lectus Lewis, 1902 and P. venustus (Erichson, 1834) (assumed to be holotypes in Lackner, 2016) is clarified., Tomáš Lackner., and Obsahuje bibliografii
In insects, allometries of exaggerated traits such as horns or mandibles are often considered species specific and constant during a season. However, given that constraints imposed by the advancing season affect the developmental processes of organisms, these allometries may not be fixed, and the switch point between morphs may vary between populations and within populations during a season. The hypothesis of such a seasonal variation in exaggerated traits was tested using the dimorphic males of the beetle Lucanus cervus. The remains of specimens killed by predators were collected along forest tracks from mid May to late August 2008 in a protected lowland forest in northern Italy. The largest beetles were collected in mid May and average size thereafter decreased. Males collected early in the season mostly had large mandibles (i.e. they belonged to the major morph). In contrast, late in the season the probability of finding males with large mandibles was very low. The threshold body size determining morph expression also shifted during the season. Early in the season, the threshold pronotum width for a 50% chance of developing into the major morph was 1.74 cm, whereas later in the season it was 1.90 cm. This shift in the threshold body size was interpreted as the effect of phenotypic plasticity in a population exposed to constraints imposed by the advancing season. and Sönke Hardersen, Anna L.M. Macagno, Roberto Sacchi, Ilaria Toni.
Male dimorphism in insects is often accompanied by alternative mating tactics, which may, together with morphological traits, determine fitness of the different male morphs. Fitness consequences of male head horn size, male-male competition and male nest-staying behaviour were experimentally assessed in Copris acutidens, in which major and minor males can co-occur in nests. Possible differences in their reproductive behaviour and breeding success were assayed in a breeding experiment, in which females were paired with one major male, one minor male, or a pair of major and minor males. The advantage of major males staying in a nest along with a rival male is that major males are reproductively more successful than minor males in this species. The weight of dung transported into nests was significantly less in rearing containers containing two males than in those with a single male of either morph, although it did not differ between major and minor males when kept alone. The results indicate that the presence of a rival male negatively affects male provisioning due to interference from rival males. In contrast, in the present study, an increased incidence of male nest-staying behaviour was recorded in the two- male and one minor male treatment than in the one major male treatment. These results indicate that because of the risk of sperm competition, major males stay longer in nests if a rival male is present. Furthermore, minor males (which are subject to a higher risk of sperm competition) stay longer than major males in nests without a rival male. In other words, the present study revealed an alternative behaviour during the post-copulatory stage associated with horn dimorphism and the presence or absence of a rival male., Mayumi Akamine., and Obsahuje bibliografii
To conserve the predators and parasitoids of agricultural pests it is necessary to understand their population structure in a mixed landscape, and to consider the spatial and temporal changes in their distribution and movement of adults and larvae. We studied the distribution and movement of the ground beetle Carabus yaconinus (Coleoptera: Carabidae), which inhabits farmland-woodland landscapes. We placed a large number of pitfall traps along the border between a wood and an orchard and counted the number of C. yaconinus adults and larvae caught in the traps from 13 April to 28 June 2005. Some of the adults were marked before they were released. Adults were most abundant at the edge of the wood and the number caught gradually decreased when entering into the wood. In contrast, larvae were only found in the interior of the wood, although they moved closer to the edge of the wood as they matured. Adult females were collected within the wood and neighbouring orchards more frequently than adult males. It is likely that females enter woodlands in search of oviposition sites and leave woodlands in search of high-protein food sources to support reproduction. For sustaining populations of C. yaconinus it is necessary to have woodlands of at least 60 m in width adjacent to farmland. It is possible to design an appropriate landscape if the habitat requirements of the predatory arthropods are well understood.
1_Prey preferences and feeding-related behaviour of a Central European species of Scydmaeninae, Euconnus pubicollis, were studied under laboratory conditions. Results of prey choice experiments involving 50 species of mites belonging to 24 families of Oribatida and one family of Uropodina demonstrated that beetles feed mostly on ptyctimous Phthiracaridae (over 90% of prey) and only occasionally on Achipteriidae, Chamobatidae, Steganacaridae, Oribatellidae, Ceratozetidae, Euphthiracaridae and Galumnidae. The average number of mites consumed per beetle per day was 0.27 ± 0.07, and the entire feeding process took 2.15–33.7 h and showed a clear linear relationship with prey body length. Observations revealed a previously unknown mechanism for capturing prey in Scydmaeninae in which a droplet of liquid that exudes from the mouth onto the dorsal surface of the predator’s mouthparts adheres to the mite’s cuticle. Morphological adaptations associated with this strategy include the flattened distal parts of the maxillae, whereas the mandibles play a minor role in capturing prey. Mechanisms for overcoming the prey’s defences depended on the body form of the mite. When attacking oribatids that adopt the ptychoid defence (encapsulation) Euconnus opened the prodorsum and pressed the anal and genital plates deeply into the idiosoma, whereas it fed on all other mites by entering their bodies through small gnathosomal or/and genital openings, after breaking off mouthparts or/and genital plates., 2_The preferential feeding of a specialized and locally abundant ant-like stone beetle on one family of Oribatida, documented here for the first time, has implications for the population dynamics of the prey and raises questions about predator-prey co-evolution and costs of an unusually prolonged period spent feeding when at risk from competition and attack by larger predators, typical of the habitats where Scydmaeninae occur., Pawel Jaloszynski, Ziemowit Olszanowski., and Obsahuje seznam literatury
The first and third larval stages of Nearctic Anisotoma blanchardi (Horn, 1880) are described in detail and figured for the first time; measurements and chaetotaxy of head, mouthparts, thorax, abdomen, leg and urogomphi are given. Larval morphology of the blanchardi group is discussed. The blanchardi species group, proposed after a study of adult characters, is very important phylogenetically because it is a basal group in the genus and sister group to all the remaining groups. Larval characters confirm the monophyly of the group. The common larval characters of the blanchardi species group are: (i) presence of primary setae below the posterior row of terga, (ii) secondary microsculpture on the head, dense, present from the base of the head to the anterolateral arms of the epicranial suture and fronto-clypeal furrow, (iii) sclerotization around sockets of primary posterior setae of thorax of instar III, (iv) presence of clypeal furrow in the third stage, (v) presence of setae Dc1, Dd1, Dc2, Dd2a on head in instar III, (vi) urogomphomere 1 and 2 similar in length and proportion.