Multiple-chromosome sex systems in the darkling beetles Blaps gigas and Blaps gibba (Coleoptera, Tenebrionidae)

We have studied mitotic and meiotic chromosomes in the males of two species of Blaps: B. gigas and B. gibba. Karyological characteristics such as the occurrence of a multivalent configuration at diakinesis and two types of metaphase-II spreads support the notion that multiple-chromosome sex systems involving five chromosomes in B. gigas and eight chromosomes in B. gibba have developed in these species. Results obtained by means of silver staining and C-banding techniques suggest that the complex sex systems occurring in B. gigas and B. gibba may have originated from exchanges of terminal ribosomal genes among the Y chromosome and some autosomes.     

Higher level molecular phylogeny of darkling beetles (Coleoptera: Tenebrionidae)

Insect diversity represents about 60% of the estimated million‐and‐a‐half described eukaryotic species worldwide, yet comprehensive and well‐resolved intra‐ordinal phylogenies are still lacking for the majority of insect groups. This is the case especially for the most species‐rich insect group, the beetles (Coleoptera), a group for which less than 4% of the known species have had their DNA sequenced. In this study, we reconstruct the first higher level phylogeny based on DNA sequence data for the species‐rich darkling beetles, a family comprising at least 20 000 species. Although amongst all families of beetles Tenebrionidae ranks seventh in terms of species diversity, the lack of knowledge on the phylogeny and systematics of the group is such that its monophyly has been questioned (not to mention those of the subfamilies and tribes contained within it). We investigate the evolutionary history of Tenebrionidae using multiple phylogenetic inference methods (Bayesian inference, maximum likelihood and parsimony) to analyse a dataset consisting of eight gene fragments across 404 taxa (including 250 tenebrionid species). Although the resulting phylogenetic framework only encompasses a fraction of the known tenebrionid diversity, it provides important information on their systematics and evolution. Whatever the methods used, our results provide strong support for the monophyly of the family, and highlight the likely paraphyletic or polyphyletic nature of several important tenebrionid subfamilies and tribes, notably the polyphyletic subfamilies Diaperinae and Tenebrioninae that clearly require substantial revision in the future. Some interesting associations in several groups are also revealed by the phylogenetic analyses, such as the pairing of Aphtora Bates with Phrenapatinae. Furthermore this study advances our knowledge of the evolution of the group, providing novel insights into much‐debated theories, such as the apparent relict distribution of the tribe Elenophorini.     

Life forms and strategies of lichen-feeding darkling beetles (Coleoptera,Tenebrionidae: Helopini)

Trophic relations of lichen-feeding darkling beetles of the tribe Helopini in Turkey, the Caucasus, and Anti-Atlas are considered. This group is the most diverse in relict Anatolian forests of Cedrus libani, Abies cilicica, Pinus nigra, Juniperus spp., and Quercus cerris, where multitaxon lichenophagous assemblages exist. Three life strategies for attenuation of interspecific competition are distinguished: (1) differentiation of the consumed lichens, (2) separation of the life forms based on the types of the lichens consumed, and (3) segregation of circadian activity in adults. We assume that adaptation of the Helopini larvae to the soil life promoted their wide distribution in different landscapes by elimination of the limiting factor for completing their life cycles, namely the need for ligneous substrate of old rotting trees. The possibility of using lichen-feeding beetles of the tribe Helopini in ecosystem and lichen indication is considered.     

台湾和日本拟步甲在纬度分布上的比较研究

台湾和日本处在不同的地理纬度上,同属岛屿海洋性气候,前者地域面积远小于后者,拟步甲的物种多样性却大于后者。为弄清楚这些科学问题,作者采用G-F指数对从台湾到日本不同纬度梯度上的拟步甲多样性分布格局进行了比较分析,得到如下初步结论：(1) G-F指数从大到小依次是：台湾(21°N-25°N)(0．826)>日本(24°N-45°N)(0．824)>日本Ⅱ纬度区(30°N-35°N)(0．792)>日本Ⅰ纬度区(24°N-30°N)(0．765)>日本Ⅲ纬度区(35°N-40°N)(0．761)>日本Ⅳ纬度区(40°N-45°N)(0．603);(2)台湾拟步甲属的多样性(DG)、族的多样性(DF)和G-F指数(DG-F)均最高,分别是4．263、24．464和0．826;(3)各纬度上拟步甲的物种分布情况：台湾(21°N-25°N)(541种)>日本(24°N-45°N)(489种)>日本Ⅰ纬度区(24°N-30°N)(257种)>日本Ⅱ纬度区(30° N-35° N)(231种)>日本Ⅲ纬度区(35° N-40° N)(172种)>日本Ⅳ纬度区(40° N-45° N)(60种)。研究数据显示, G-F指数能较好地反映台湾和日本各地拟步甲族、属的多样性。其物种多样性在纬度上的分布表现为从南向北递减的趋势,并对其基本原因进行分析。作者首次基于台湾和日本两个岛屿拟步甲物种多样性的比较分析,对现有岛屿生物多样性的有关理论提出个人看法,认为岛屿生物地理学的“物种-面积关系理论”中的“岛屿面积越大,物种数量就越多”可能存在一定的局限性,不一定能客观地反映种类众多的现生岛屿昆虫物种多样性的实际情况。     

Spatial structure of community of darkling beetles (Coleoptera: Tenebrionidae) in the Negev Highlands, Israel

The distribution of niches in resource space of darkling beetles of Negev desert, Israel were studied using discriminant analysis Seventeen environmental variables (substrate structure and vegetation) were measured at 375 plots within 15 grids The first three discriminant axes account for 77% of the variance and reflect a soil structure gradient from sand to clay (the first axis), a gradient of increasing productivity (the second axis), and a type of vegetation architecture (the third axis) Abundance and biomass of tenebrionids increased linearly along the first, the second and the third axes Species richness and diversity had a slanting parabola shape along the substrate axis and increased along the productivity axis There were two distinct spatial guilds of tenebrionid species One guild was composed by species that preferred sandy-gravel soils, and another guild consisted of species that preferred clay soils Niche overlapping of the "sandy-gravel" species was lower than that of the "clay" species Niches of the "sandy-gravel" species were randomly distributed in the resource space Those of the "clay" species formed a tight cluster with most niches placed in the center of the space, representing the centrifugal type of organization The conformity of the guild structure with the different types of organization was supported by compansons between empirical data and stochastic models The border between these two guilds matches with proposed earlier biogeographical boundary (Ramon-Zohar line)     

The taxocene of lichen-feeding darkling beetles (Coleoptera,Tenebrionidae: Helopini) in a forest-steppe ecotone

The taxocene of lichen-feeding darkling beetles from the tribe Helopini is studied in the steppes of the south of Rostov Province. The species of lichens grazed on by the representatives of this tribe are identified for the first time and dependence of circadian activity and spatial distribution of adults on temperature and air humidity is shown. Global warming and human activities may have caused degradation of steppe lichen communities that formed the dietary base for the lichen-feeding darkling beetles in natural ecosystems. As a result, 3 out of 4 beetle species completely left steppe biotopes for tree shelterbelts. This caused a change in the trophic relationships (transition from epigeic to epiphytic lichens) and in the spatial distribution of darkling beetles, promoted the establishment of competitive interactions, and increased the duration of circadian and seasonal activity due to the lengthening of the periods with optimum temperature and air humidity for each species.     

A new genus and species of darkling beetles of the tribe Helopini (Coleoptera,Tenebrionidae) from Turkey

A new genus and species Microdocnemis xerophilicus gen. et sp. n. of the tenebrionid-beetle tribe Helopini is described from southwestern Turkey. The new genus belongs to the cylindrinotoid group of genera and is closely related to the genus Odocnemis Allard, 1876 in the structure of the male genitalia and female genital tubes and in the denticulation of the inner margin of the fore tibia. Microdocnemis differs from Odocnemis in the following characters: body very weakly flattened dorsally and ventrally; apical part of elytra, body ventrally, and epipleura with hairs; anal sternite with double bordering; apical margins of tibiae with short thick spines. The only species of the new genus inhabits xerophytic stony biotopes and has been found under stones; the species of the genus Odocnemis live on tree trunks covered with lichens.     

Pythiopina,an enigmatic subtribe of darkling beetles (Coleoptera: Tenebrionidae: Pedinini): taxonomic revision,microtomography, ecological niche models and phylogenetic position

Morphological, anatomical, and distributional data concerning the S outh A frican endemic beetle subtribe P ythiopina (T enebrionidae: P edinini) are revised. Five species, representing two genera, are recognized. Included in this total is one new species (Meglyphus mariae K amiński sp.n. ). The following species are placed in synonymy: Meglyphus ciliatipes [=Meglyphus calitzensis syn.n. ]; Meglyphus laenoides [=Meglyphus andreaei syn.n. ; =Meglyphus namaqua syn.n. ]. Microtomographic models for all valid P ythiopina species, including the holotype of the newly described species, are presented and analysed. Endoskeleton morphology (specifically characters of the tentorium and metendosternite) proved to be informative at the specific and generic levels. An identification key is provided to all known species of the subtribe. Environmental niche models are presented for the majority of species. A molecular phylogeny of P edinini based on six genetic loci (28S : D 1–D 3 region; 28S : D 4–D 5 region, COII , A rgK , CAD 2, wg) was also produced to explore the phylogenetic position of P ythiopina. This analysis is the first to include representatives of all seven subtribes of P edinini, and supports a sister relationship between P ythiopina and the P alaearctic subtribe D endarina. Results also suggest the existence of a second pair of sister taxa within P edinini (in addition to M elambiina) with an amphitropical A frican distribution. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:285AD87A‐46B1‐4FE9‐BC57‐949EA1F70D49 .     

Home range size in two darkling beetle species (Coleoptera,Tenebrionidae) from Southern Kazakhstan

The repeated collecting of marked darkling beetle species, including the diurnal species Tentyria gigas and the nocturnal species Cyphogenia gibba from Kazakhstan demonstrated that their home ranges constituted 457 and 360 m², respectively. More than 500 beetles from an area of 2.5 ha were marked by engraving numbers on their elytra. Beetles were observed during two seasons at a distance covering 2 km from the site of release. Sex was determined in a quarter of all the beetles. In females and males of T. gigas, the home range constituted 700 and 552 m², respectively; in C. gibba, 599 and 343 m², respectively. Small home ranges of these species can be explained by the presence of numerous predators, occasional death of beetles under cattle’s hoofs, and a great number and high density of shelters.     

Reevaluation of Blapimorpha and Opatrinae: addressing a major phylogeny‐classification gap in darkling beetles (Coleoptera: Tenebrionidae: Blaptinae)

The taxonomic concepts of Blapimorpha and Opatrinae (informal and traditional, morphology‐based groupings among darkling beetles) are tested using molecular phylogenetics and a reassessment of larval and adult morphology to address a major phylogeny‐classification gap in Tenebrionidae. Instead of a holistic approach (family‐level phylogeny), this study uses a bottom‐up strategy (tribal grouping) in order to define larger, monophyletic lineages within Tenebrioninae. Sampling included representatives of 27 tenebrionid tribes: Alleculini, Amarygmini, Amphidorini, Blaptini, Bolitophagini, Branchini, Cerenopini, Coniontini, Caenocrypticini, Dendarini, Eulabini, Helopini, Lagriini, Melanimini, Opatrini, Pedinini, Phaleriini, Physogasterini, Platynotini, Platyscelidini, Praociini, Scaurini, Scotobiini, Tenebrionini, Trachyscelini, Triboliini and Ulomini. Molecular analyses were based on DNA sequence data from four non‐overlapping gene regions: carbamoyl‐phosphate synthetase domain of rudimentary (CAD) (723 bp), wingless (wg) (438 bp) and nuclear ribosomal 28S (1101 bp) and mitochondrial ribosomal 12S (363 bp). Additionally, 15 larval and imaginal characters were scored and subjected to an ancestral state reconstruction analysis. Results revealed that Amphidorini, Blaptini, Dendarini, Pedinini, Platynotini, Platyscelidini and Opatrini form a clade which can be defined by the following morphological features: adults—antennae lacking compound/stellate sensoria; procoxal cavities externally and internally closed, intersternal membrane of abdominal ventrites 3–5 visible; paired abdominal defensive glands present, elongate, not annulated; larvae—prolegs enlarged (adapted for digging); ninth tergite lacking urogomphi. To accommodate this monophyletic grouping (281 genera and ～4000 species), the subfamily Blaptinae sens. nov. is resurrected. Prior to these results, all of the tribes within Blaptinae were classified within the polyphyletic subfamily Tenebrioninae. The non‐monophyletic nature of Terebrioninae has already been postulated by previous authors, yet no taxonomic decisions were made to fix its status. The reinstatement of Blaptinae, which groups ～50% of the former Tenebrioninae, helps to clarify phylogenetic relations among the whole family and is the first step towards a complete higher‐level revision of Tenebrionidae. The Central Asian tribe Dissonomini (two genera, ～30 species) was not included in Blaptinae due to a lack of representatives in the performed phylogenetic analyses; however, based on morphological features, the tribe is listed as a potential addition to the subfamily.     

Susceptibility of last instar red flour beetles and confused flour beetles (Coleoptera: Tenebrionidae) to hydroprene.

Last instar larvae of the red flour beetle, Tribolium castaneum (Herbst), and the confused flour beetle, Tribolium confusum Jacquelin du Val, were either exposed for 8-144 h on concrete treated with 1.9 x 10(-3) mg(AI)/per cm2 hydroprene, or continually exposed on concrete treated with 9.8 x 10(-4) to 1.9 x 10(-3) mg[AI]/per cm2 hydroprene. In both tests, larvae were exposed and held at 27 or 32 degrees C and 40, 57, or 75% RH. When larvae were exposed with no food to hydroprene for different time intervals, then transferred to untreated concrete containing flour, consistent effects were produced only at 144 h. At this exposure interval, the percentage of beetles arrested in the larval stage after 3-4 wk was generally greater at 75% RH compared with 40 and 57% RH, but there were no differences between species or temperature. The percentages of dead adult red flour beetles and live adults with morphological deformities were also greatest at 75% RH, and defects were more prevalent in red flour beetles than in confused flour beetles. When larvae were continually exposed to different concentrations of hydroprene on concrete that contained flour, the percentage of arrested larvae, dead adults, and live adults of both species generally increased with concentration. There were more deleterious effects at 75% RH compared with either 40 or 57% RH, and effects were more pronounced in the red flour beetle compared with the confused flour beetle. In both experiments, temperature effects were variable and inconclusive. Results indicate that continual exposure of last instar red flour beetle and confused flour beetle to hydroprene can limit population development, but exposure intervals of >6 d may be required for maximum effectiveness.     

Optimal hatching conditions of Zophobas atratus (Coleoptera: Tenebrionidae) eggs under various culture conditions

Supermealworm, Zophobas atratus (Coleoptera: Tenebrionidae) is a tropical species used for human consumption and as an ingredient in animal feed. We investigated the hatching characteristics of Z. atratus eggs under varying conditions to optimize artificial rearing conditions. Overall, the average egg weight, width, and length decreased by 42.3%, 3.7%, and 10.1%, respectively, on the 6th day post-oviposition. We varied either temperature, photoperiod, illuminance, or humidity, while the other conditions remained constant. Of the four experimental temperatures—25 °C, 27 °C, 30 °C, and 33 °C–30 °C was associated with the highest hatching rate (91.0%) during days 5–7. Although other experimental conditions did not have a significant effect on hatchability, we were able to elucidate the ideal conditions for improved hatchability. For photoperiod, hatchability was the highest (84%) at 12L/12D, followed by 81.0% at 15L/9D, and 70% at 9L/15D. Among the illuminance conditions tested—600, 1800, and 3000 lx—hatchability was the highest at 1800 lx (82.3% on days 4–6). Among the relative humidity (RH) levels tested—50%, 65%, and 80%—hatchability was the highest at 65% RH (88.5% on days 5–6). Thus, the ideal conditions for maximum hatchability were 30 °C, 12L/12D, 65% RH, and 1800 lx. Under these combined conditions, the hatching rate increased by 93.6%, and the hatching time was reduced by two days.     

The oldest opatrine terrestrial darkling beetle (Coleoptera: Tenebrionidae: Tenebrioninae) from the Paleocene of Menat (France)

The oldest terrestrial darkling beetle of the opatrine lineage, Palaeosclerum pohli gen. et. sp. nov. (subfamily Tenebrioninae) is described from the Middle Paleocene of Menat (France). The complex of characters, combining the peculiar shape of body (robust, adapted to a fossorial lifestyle), structure of fossorial protibia, 5-segmented antennal club demonstrates a considerable similarity of the new genus to the extant representatives of the ‘sclerina’ generic group of the subtribe Opatrina. Palaeosclerum gen. nov. is compared with recent genera Sclerum Dejean, 1834, Platynosum Mulsant and Rey, 1859 and Eurycaulus Fairmaire, 1868.     

洋虫成虫脱脂蛋白酶解液的抗氧化作用

对洋虫Martianus dermestoides Chevrolat成虫脱脂蛋白酶解液的抗氧化作用进行了研究。用木瓜蛋白酶水解洋虫成虫脱脂蛋白,用截留分子量分别为10 kDa和6 kDa的超滤膜将其分离成3个组分,用邻苯三酚 鲁米诺发光法、DPPH自由基清除法、Fenton法和Oyaizu法,分别测定不同分子量的洋虫成虫脱脂蛋白酶解液清除超氧阴离子自由基、DPPH自由基及羟基自由基的能力。结果表明：洋虫成虫蛋白酶解液3个组分都有很好的清除自由基能力,且还原性较强,以分子量＜6 kDa的组分清除效果最佳(P＜0.05)。结果揭示洋虫成虫脱脂蛋白酶解液具有很好的抗氧化作用。     

A multidimensional characterization of rarity applied to the Aegean tenebrionid beetles (Coleoptera Tenebrionidae)

This paper attempts to use museum collection data to estimate measures of species rarity and then to relate these measures to extinction risk. For this purpose, 170 taxa (138 species and 32 subspecies) of tenebrionid beetles from 32 Aegean Islands (Greece) were considered. For each taxon, rarity was evaluated as geographic distribution (mean incidence on islands in the archipelago), potential habitat exploitation (total area of the islands occupied on the total area of the study system) and contactability (number of decades of taxon’s records on the total number of decades of assumed persistence from 1870 to 2000). All of these indices were correlated to each other. Whether expressed in terms of range size or habitat exploitation rarity was a major determinant of a species’ risk of extinction (evaluated as extinction decade). Thus, the designation of rarity provides a good basis for identifying species that are most in need of conservation at a particular scale.     

Climatic correlates of body size in European tenebrionid beetles (Coleoptera: Tenebrionidae)

Tenebrionidae are one of the largest families of beetles and are known for their adaptations to hot and dry climates. An increase in body size also increases the volume/surface area ratio, which reduces transpiration, and hence water loss. If an increase in body size is an important adaptation in tenebrionids to cope with increasing aridity, we expect a correlation between body size and climatic gradients in the major tenebrionid clades. Alternatively, we can postulate that arid climates do not drive body size evolution, but rather select, from a wider fauna containing species of any size, those that have larger bodies. In this case we expect that drier regions will host faunas that contain, on average, larger species. To test the first hypothesis, we correlated inter-specific body size variation in the main tenebrionid clades with climatic gradients in Europe. We found only weak trends. To test the second hypothesis, we regressed mean body size of European country faunas against climatic characteristics. We found a strong increase in body size in southern faunas experiencing hot and dry climates. Therefore, increase in body size is not a major adaptation in tenebrionid evolution, but climate is an important filtering factor that determines a prevalence of larger species in southern Europe.     

Complete mitochondrial genome of the darkling beetle Gonocephalum outreyi (Coleoptera: Tenebrionidae) with phylogenetic implications

The complete mitochondrial genome (mitogenome) of Gonocephalum outreyi was determined by using next-generation sequencing approach. The full length of this mitogenome is 15,836?bp, which consists of 37 typical metazoan mitochondrial genes with an identical genome organization to ancestral insects. The majority of the protein-coding genes begin with the codon ATN, except for cox1 and cox2 with AAT and AAA, respectively. To elucidate the phylogenetic position of G. outreyi, we used various sequence coding schemes for protein-coding genes and the combined nucleotide sequences of all mitochondrial genes for tree building under the Bayesian and Maximum Likelihood inferences. The phylogenetic results consistently supported G. outreyi as a member of the family Tenebrionidae. The monophyly of both Tenebrionoidea and Tenebrionidae were strongly supported. The Scraptiidae and Melandryidae were recovered to be non-monophyletic in regards to the Osphya. Within Tenebrionidae, the subfamilies Diaperinae and Tenebrioninae were found to be non-monophyletic.     

Selection for high and low amylase activity in adult flour beetles (Tribolium confusum) (Coleoptera,Tenebrionidae)

As a result of selection for high amylase activity in two strains of the flour beetle Tribolium confusum, mean activity considerably increased. Selection for low activity was ineffective in one strain, and mean activity increased, contrary to expectation, in the downward-selection line of the other.Heritabilities of amylase activity were 0.52 and 0.18 for the two strains (estimated by offspring-midparent regression in generation 1). Environmental factors have considerable effects on activity.The outcome of selection and possible models for the genetic control of amylase activity in Tribolium are discussed.