Male Abdomen Research Articles

Identification and Expression Profiling of Odorant Receptor Protein Genes in Sitophilus zeamais (Coleoptera: Curculionoidea) Using RT-qPCR.

This study aimed to identify ORs (odorant receptors) and Orco (odorant receptor coreceptor) genes in Sitophilus zeamais Motschulsky (Coleoptera: Curculionoidea), to explore the relative expression levels of these genes in different adult tissues and obtain information on highly expressed receptor proteins. Putative OR and Orco genes were identified from transcriptomic data previously obtained for S. zeamais using bioinformatics methods. Quantitative real-time PCR was used to compare the differences in expression in seven adult tissues (male antennae, female antennae, heads, thoraxes, abdomens, wings, and legs). The candidate OR and Orco gene sequences were analyzed, and the protein physicochemical properties were predicted. We identified 64 OR genes including the Orco gene. Forty-seven OR genes, including Orco, were over expressed in male or female antennae. Seventeen OR genes appeared to be expressed at elevated levels in male antennae. Twenty-nine genes were expressed at significantly elevated levels in female antennae. In total, 11 OR genes were selected for further sequence analysis. The selected proteins were structurally characterized, and bioinformatics analysis was performed. Overall, in this study, candidate ORs of S. zeamais have been identified for the first time, and these ORs could be molecular targets for interference in the insect olfactory system.

Molecular basis of wax-based color change and UV reflection in dragonflies.

Many animals change their body color for visual signaling and environmental adaptation. Some dragonflies show wax-based color change and ultraviolet (UV) reflection, but the biochemical properties underlying the phenomena are totally unknown. Here we investigated the UV-reflective abdominal wax of dragonflies, thereby identifying very long-chain methyl ketones and aldehydes as unique and major wax components. Little wax was detected on young adults, but dense wax secretion was found mainly on the dorsal abdomen of mature males of Orthetrum albistylum and O. melania, and pruinose wax secretion was identified on the ventral abdomen of mature females of O. albistylum and Sympetrum darwinianum. Comparative transcriptomics demonstrated drastic upregulation of the ELOVL17 gene, a member of the fatty acid elongase gene family, whose expression reflected the distribution of very long-chain methyl ketones. Synthetic 2-pentacosanone, the major component of dragonfly's wax, spontaneously formed light-scattering scale-like fine structures with strong UV reflection, suggesting its potential utility for biomimetics.

New Middle Jurassic fossils shed light on the relationship of recent Panorpoidea (Insecta, Mecoptera)

ABSTRACT Examination of a diverse and abundant collection of Middle–Upper Jurassic scorpionflies from the Jiulongshan Formation of Daohugou village in Inner Mongolia, China, has enabled a further delimitation of the morphological variability of the polyphyletic family Orthophlebiidae. The family Protorthophlebiidae fam. nov. is herein erected on the basis of new characters present in new specimens of Protorthophlebia Tillyard, 1933 preserved with bodies. An emended diagnosis of the genus Orthophlebia is provided, adding morphological characters of the male abdomen and the head, and revising those of the wing venation. A new genus and species within the family Orthophlebiidae, Juraphlebia eugeniae gen. et sp. nov., and a new species of the genus Orthophlebia Westwood, 1845, O. chinensis sp. nov, are described. In the light of the new systematic concept and new taxonomic data relationships within the superfamily Panorpoidea and between the two modern families Panorpidae and Panorpodidae are discussed. urn:lsid:zoobank.org:pub:4C439272-F435-4AF6-A770-13868E990D4A

Sexually dimorphic gene expression and transcriptome evolution provide mixed evidence for a fast-Z effect in Heliconius.

Sex chromosomes have different evolutionary properties compared to autosomes due to their hemizygous nature. In particular, recessive mutations are more readily exposed to selection, which can lead to faster rates of molecular evolution. Here, we report patterns of gene expression and molecular evolution for a group of butterflies. First, we improve the completeness of the Heliconius melpomene reference annotation, a neotropical butterfly with a ZW sex determination system. Then, we analyse RNA from male and female whole abdomens and sequence female ovary and gut tissue to identify sex‐ and tissue‐specific gene expression profiles in H. melpomene. Using these expression profiles, we compare (a) sequence divergence and polymorphism; (b) the strength of positive and negative selection; and (c) rates of adaptive evolution, for Z and autosomal genes between two species of Heliconius butterflies, H. melpomene and H. erato. We show that the rate of adaptive substitutions is higher for Z than autosomal genes, but contrary to expectation, it is also higher for male‐biased than female‐biased genes. Additionally, we find no significant increase in the rate of adaptive evolution or purifying selection on genes expressed in ovary tissue, a heterogametic‐specific tissue. Our results contribute to a growing body of literature from other ZW systems that also provide mixed evidence for a fast‐Z effect where hemizygosity influences the rate of adaptive substitutions.

Skeleton and musculature of the male abdomen in Tanyderidae (Diptera, Nematocera) of the Southern Hemisphere.

The structure of the male terminalia and their musculature of species of tanyderid genera Araucoderus Alexander, 1929 from Chile and Nothoderus Alexander, 1927 from Tasmania are examined and compared with each other and with published data on the likely relatives. The overall pattern of male terminalia of both genera is similar to those of most Southern Hemisphere genera, with simple curved gonostyli, lobe-like setose parameres, and setose cerci inconspicuous under the epandrium. Both genera have terminalia similarly rotated by 180° (and 90° as an intermediate stage); rotation may be either clockwise or counterclockwise. However, the similar patterns are realized differently: segment VIII is the decreased and asymmetrical due to completely membranose tergite VIII in Nothoderus (the first record of such modification in Tanyderidae), but narrow and symmetrical in Araucoderus. Accordingly, pregenital muscles are very different between the genera. Based on localization of muscle attachment sites, the hypandrial origin of the stripe between gonocoxites is shown in both genera, and entire membranization of tergite VIII and partial membranization of hypoproct is shown in Nothoderus. Tanyderidae are characterized by highly specialized sclerites and muscles of male terminalia and provide no evidence of relationship with previously studied members of Psychodidae, Blephariceridae and Ptychopteridae.

The identification of the species of the ‘Spilogona contractifrons species-group’ and the ‘Spilogona nitidicauda species-group’ (Diptera, Muscidae) based on morphological and molecular analysis

Muscid species of the ‘Spilogona contractifrons species-group’ (Spilogona alticola (Malloch, 1920), S. arctica (Zetterstedt, 1838), S. contractifrons (Zetterstedt, 1838), S. orthosurstyla Xue & Tian, 1988) and of the ‘Spilogona nitidicauda species-group’ (S. nitidicauda (Schnabl, 1911), S. hissarensis Hennig, 1959, S. imitatrix (Malloch, 1921), S. platyfrons Sorokina, 2018) are notoriously difficult to distinguish. In this paper, their morphological features are analysed, images of the male head, frons and abdomen of all the species are given, and the male terminalia are figured. The study of extensive material has shown that all the morphologically recognised species in each of these groups are valid species. An identification key is provided for both groups of species. To confirm the morphological differences, genetic differences in the cytochrome oxidase I gene of flies of the ‘Spilogona contractifrons species-group’ and of the ‘Spilogona nitidicauda species-group’ were analysed. It is shown that members of both groups of species have not only distinguishing morphological characters but also fixed substitutions in the DNA sequences. Since a low interspecific polymorphism is known in the Muscidae Latreille, 1802, the revealed genetic distances confirm the existence of separate species or subspecies in each of the groups studied.

Linear viscoelastic and microstructural properties of native male human skin and in vitro 3D reconstructed skin models

The study reports first ever account of measurements of linear viscoelastic moduli under small amplitude oscillatory shear deformations, for commercially available juvenile and aged in vitro 3D reconstructed skin models. The results were compared with those of native male whole human and dermis-only foreskin samples, catering to a wide age group from 0.5 to 68 years, including samples from a 23-year-old male abdomen. In the strain sweep tests, the dermis of the juvenile/young age group assumed a higher intrinsic elastic modulus than the whole skin. A reverse qualitative trend was noted for the adult/aged age group. Confirmed by the histological examination of the stained cross-sections, this is attributed to the nascent epidermal differentiation and the high fiber density of dermal collagen. The oscillation frequency sweeps exposed a greater dependence of the elasticity on the frequency for the native male dermis foreskin samples as compared to the whole skins, irrespective of age. This is anticipated since the extremely structured epidermis confers higher resistance to the whole skins towards intracycle deformations compared to the dermis, thereby storing smaller elastic energy. The 3D skin models examined in this work exhibited a broader linear viscoelastic region, a larger viscoelasticity, and much higher dynamic moduli, compared to the native skin. The rheological trends are a significant addition to the literature and may be used as a reference for the design of next generation of scaffolds.

Sensilla on organs of female and male Aphidius gifuensis (Hymenoptera: Aphidiidae).

Aphidius gifuensis Ashmaed parasitizes several species of aphids that cause economic damage to globally important crops; however, the mechanism of host location in this species is unclear. Here, we studied the sensory system in A. gifuensis to explore the likely mechanisms of host location that could be useful in the improved application of this species in aphid biological control programs. We used scanning electron microscopy to observe the external morphologies of the sensilla recorded from the entire body of female and male A. gifuensis. We recorded 16-18 segments and five types of sensilla on female antennae, including Böhm bristle, Chaetica sensillum, basiconic sensillum, trichoid sensillum, and placodea sensillum. The male antennae consisted of 18-20 segments, and distribution of sensilla was similar to female antennae with minor differences. No hole on the surface or tip of the sensilla was observed. Interestingly, scattered pores around the TS were found on the entire body of females, but only from the antennae, abdomen, and thoracic legs in males. TS was the most abundant and widely distributed sensillum. Tympana structures were found on antennae and femur of thoracic legs. Antenna cleaner was found on the tibia of propodeum and wing cleaner was found on the tibia of metapedes. Special crevice-shaped structures were found on the abdomen in both sexes, whereas strip-shaped structures were found only on the abdomen of females. Possible functions of the sensilla in relation to their morphologies are discussed.

Morphological changes in different caste adult ant specificities of Polyrhachis vicina Roger (Hymenoptera, Formicidae) caused in estrogen-related receptor

The estrogen-related receptor (ERR) gene is a member of the nuclear receptor subfamily. Previous studies have indicated that ERR plays important roles in regulating insect growth and development. How ERR is associated with ant caste specificities remains unclear. In this study, we attempted to identify the role of ERR in the regulation of different adult caste specificities of Polyrhachis vicina Roger. Significant variations were detected in the ants including PvERR expressions, some physiological indexes and morphological traits including survival rate, body weight, body length, head width and abdominal appearance by different techniques. The results revealed that when PvERR expressions is up-regulated, boundaries of the abdominal segments were indistinct on the ventral side of the abdomen in males. Down-regulation of PvERR expressions caused abdominal swelling in males and a distended ventral abdomen in females and workers. Variation in PvERR expressions led to a remarkable decline in ant survival rates, particularly for males. These results indicated that different caste adults appeared to have different degrees of sensitivity in physiological response and morphological changes caused by variation in PvERR expressions. Thus, our data demonstrate that PvERR plays an important role in regulating the different adult caste specificities of P. vicina.

Silencing of Chemosensory Protein Gene NlugCSP8 by RNAi Induces Declining Behavioral Responses of Nilaparvata lugens.

Chemosensory proteins (CSPs) play imperative functions in chemical and biochemical signaling of insects, as they distinguish and transfer ecological chemical indications to a sensory system in order to initiate behavioral responses. The brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae), has emerged as the most destructive pest, causing serious damage to rice in extensive areas throughout Asia. Biotic characteristics like monophagy, dual wing forms, and annual long-distance migration imply a critical role of chemoreception in N. lugens. In this study, we cloned the full-length CSP8 gene from N. lugens. Protein sequence analysis indicated that NlugCSP8 shared high sequence resemblance with the CSPs of other insect family members and had the typical four-cysteine signature. Analysis of gene expression indicated that NlugCSP8 mRNA was specifically expressed in the wings of mated 3-day brachypterous females with a 175-fold difference compare to unmated 3-day brachypterous females. The NlugCSP8 mRNA was also highly expressed in the abdomen of unmated 5-day brachypterous males and correlated to the age, gender, adult wing form, and mating status. A competitive ligand-binding assay demonstrated that ligands with long chain carbon atoms, nerolidol, hexanal, and trans-2-hexenal were able to bind to NlugCSP8 in declining order of affinity. By using bioinformatics techniques, three-dimensional protein structure modeling and molecular docking, the binding sites of NlugCSP8 to the volatiles which had high binding affinity were predicted. In addition, behavioral experiments using the compounds displaying the high binding affinity for the NlugCSP8, revealed four compounds able to elicit significant behavioral responses from N. lugens. The in vivo functions of NlugCSP8 were further confirmed through the testing of RNAi and post-RNAi behavioral experiments. The results revealed that reduction in NlugCSP8 transcript abundance caused a decrease in behavioral response to representative attractants. An enhanced understanding of the NlugCSP8 is expected to contribute in the improvement of more effective and eco-friendly control strategies of BPH.

Expression Profiles and Functional Characterization of Two Odorant-Binding Proteins From the Apple Buprestid Beetle Agrilus mali (Coleoptera: Buprestidae).

The apple buprestid beetle, Agrilus mali Matsumura (Coleoptera: Buprestidae), can respond to various volatiles, but the underlying mechanism of odorant perception for this insect is poorly understood. Here, we cloned A. mali's odorant-binding proteins 3 (AmalOBP3) and 8 (AmalOBP8) and characterized their expression patterns and binding profiles. Sequence and phylogenetic analyses showed that AmalOBP3 and AmalOBP8 were distributed in the classic and minus-C OBP subfamily, respectively. AmalOBP3 was specifically and abundantly expressed in antennae of both sexes. AmalOBP8 displayed high transcript levels in antennae of both sexes, abdomens of males, and wings of both sexes. Both AmalOBPs exhibited much higher expression in male antennae than in female antennae, suggesting that they could be important in perception of male-specific olfactory cues (e.g., some sex pheromones). Out of the 40 odorant ligands tested, AmalOBP3 and AmalOBP8 bound to 15 and 21 different odorants, respectively, indicating a distinct and selective binding profile for them. Both AmalOBPs seemed to have very strong binding affinity to aliphatic alcohols and aldehydes with 12 to 15 carbon atoms. Alcohols, esters, and terpenoids were more likely to be good ligands for both AmalOBPs than aldehydes and alkanes. Together with its broad expression in different tissues, strong binding with higher numbers of putative ligands for AmalOPB8 means that this protein can have more extensive functional roles in chemosensation of A. mali. Our results provide insights into the molecular basis of chemosensation in A. mali, as well as a basis for developing detection, monitoring, and management tools for this serious pest.

New Mesopsyllus species from the Bohai Sea, China, re-evaluation of the validity of Vibriopsyllus Kornev & Chertoprud, 2008 and proposal of Sympodella gen. n. (Copepoda, Harpacticoida, Canthocamptidae).

Two new species of the genus Mesopsyllus Por, 1960 (Canthocamptidae) are described from the Bohai Sea, eastern China. Mesopsyllus dimorphus sp. n. and M. spiniferus sp. n. differ from their congeners by the presence of two instead of three outer spines on P2–P3 exp-3. They can be differentiated from each other by (1) number of inner setae on P3–P4 enp-2; (2) anterior margin of antennulary segment 7 of male; (3) ornamentation of male abdomen; (4) sexual dimorphism on P2 endopod and P3–P4 exp-3; and (5) differences in length of setae on male P5. Some observations in the original description of M. atargatis Por, 1960 are reinterpreted and the type material of M. secundus (Wells, 1965) is re-examined. Comparison between the type species of Vibriopsyllus Kornev & Chertoprud, 2008 and the four known species of Mesopsyllus shows the former as a junior subjective synonym of the latter. Consequently, Vibriopsyllus curviseta Kornev & Chertoprud, 2008 is formally transferred to Mesopsyllus as M. curvisetus (Kornev & Chertoprud, 2008), comb. n. A key to species and an updated generic diagnosis of Mesopsyllus are presented.The taxonomic status of the genus Carolinicola Huys & Thistle, 1989 is re-evaluated. The characters of its type species, C. trisetosa (Coull, 1973), indicate that the latter (and – by inference – the genus Carolinicola) should remain in the Danielsseniinae. Carolinicola galapagoensis Mielke, 1997 is fixed as the type species of a new genus Sympodella gen. n. and placed in the Hemimesochrinae (Canthocamptidae) as the putative sistertaxon of Pusillargillus Huys & Thistle, 1989. The relationships and potential synonymy of the genera Pyrocletodes Coull, 1973, Perucamptus Huys & Thistle, 1989 and Isthmiocaris George & Schminke, 2003 are briefly discussed.

The male abdominal, genital and pregenital sclerites and musculature in Neria commutata (Czerny, 1930) (Diptera, Micropezidae)

The muscles of the male abdomen and genitalia of Micropezidae were studied for the first time by the example of Neria commutata (Czerny, 1930). Based on analysis of the sclerites and musculature of the male genitalia of Micropezidae as compared to those of the previously studied Acalyptratae and Aschiza, we revealed several apomorphies of this group. The hypandrial complex is characterized by the presence of the phallic retractors and protractors M1 and M2, and the epandrial complex, by the presence of muscles M3 of the subepandrial sclerite, muscles M4 of the surstyli, muscles M7 of the cerci, and also the tergosternal muscles M5; all these muscles correspond to the ground plan of Cyclorrhapha. The following characters are considered apomorphic: the splitting of intersegmental sternal muscles ISM5–6 into 4 pairs that ensure the functioning of the forcipate appendages of sternite V; development of syntergosternite VII and reduction of muscles ISM6–7; the splitting of muscles M3 of the subepandrial sclerite into 4 pairs, enhancing the function of this sclerite; the appearance of pregonites with the associated muscles M42, which probably occurred independently several times in the evolution of different groups of Cyclorrhapha; asymmetry of syntergosternites VII and VIII and their muscles. The sclerites and muscles of the epandrium and hypandrium are characterized by complete symmetry.

Life history traits and patterns of sexual dimorphism in the freshwater crab Potamon ibericum (Bieberstein, 1809) (Decapoda: Brachyura: Potamidae) from the western Alborz Mountains, Iran

The assessment of life history traits can help to better understand the population dynamics of the respective species. We present some life history traits of the freshwater crab Potamon ibericum (Bieberstein, 1809) from the western Alborz Mountains, Iran. Carapace size at the onset of morphometric maturity was estimated using the breakpoint of the relative growth of the chela and abdomen in males and females, respectively, by implementing piecewise linear regressions. In order to quantify variations in the estimated breakpoint, a bootstrap resampling method was applied. Allometric trajectories of chelar dimensions were also applied to juveniles and adults. Sexual size dimorphism was evaluated using the dimensions of the carapace and chelae, and patterns of the carapace shape dimorphism were investigated by implementing geometric morphometric analysis. The results showed that females reach morphometric maturity at smaller sizes than males, which could be of advantage in the fluctuating environment of their freshwater habitat in order to mate as soon as possible and increase fecundity. Positive allometric trends in the length of the major chela was observed in adults of both sexes, and the possible adaptive forces on the evolution of this pattern are discussed. Results of sexual dimorphism analyses confirmed male-biased sexual size dimorphism and functional adaptation of carapace shape in both sexes.

128 slice computed tomography dose profile measurement using thermoluminescent dosimeter

The increasing use of computed tomography (CT) in clinical practice marks the needs to understand the dose descriptor and dose profile. The purposes of the current study were to determine the CT dose index free-in-air (CTDIair) in 128 slice CT scanner and to evaluate the single scan dose profile (SSDP). Thermoluminescent dosimeters (TLD-100) were used to measure the dose profile of the scanner. There were three sets of CT protocols where the tube potential (kV) setting was manipulated for each protocol while the rest of parameters were kept constant. These protocols were based from routine CT abdominal examinations for male adult abdomen. It was found that the increase of kV settings made the values of CTDIair increased as well. When the kV setting was changed from 80 kV to 120 kV and from 120 kV to 140 kV, the CTDIair values were increased as much as 147.9% and 53.9% respectively. The highest kV setting (140 kV) led to the highest CTDIair value (13.585 mGy). The p-value of less than 0.05 indicated that the results were statistically different. The SSDP showed that when the kV settings were varied, the peak sharpness and height of Gaussian function profiles were affected. The full width at half maximum (FWHM) of dose profiles for all protocols were coincided with the nominal beam width set for the measurements. The findings of the study revealed much information on the characterization and performance of 128 slice CT scanner.

A reference gene set for sex pheromone biosynthesis and degradation genes from the diamondback moth, Plutella xylostella, based on genome and transcriptome digital gene expression analyses

BackgroundFemale moths synthesize species-specific sex pheromone components and release them to attract male moths, which depend on precise sex pheromone chemosensory system to locate females. Two types of genes involved in the sex pheromone biosynthesis and degradation pathways play essential roles in this important moth behavior. To understand the function of genes in the sex pheromone pathway, this study investigated the genome-wide and digital gene expression of sex pheromone biosynthesis and degradation genes in various adult tissues in the diamondback moth (DBM), Plutella xylostella, which is a notorious vegetable pest worldwide.ResultsA massive transcriptome data (at least 39.04 Gb) was generated by sequencing 6 adult tissues including male antennae, female antennae, heads, legs, abdomen and female pheromone glands from DBM by using Illumina 4000 next-generation sequencing and mapping to a published DBM genome. Bioinformatics analysis yielded a total of 89,332 unigenes among which 87 transcripts were putatively related to seven gene families in the sex pheromone biosynthesis pathway. Among these, seven [two desaturases (DES), three fatty acyl-CoA reductases (FAR) one acetyltransferase (ACT) and one alcohol dehydrogenase (AD)] were mainly expressed in the pheromone glands with likely function in the three essential sex pheromone biosynthesis steps: desaturation, reduction, and esterification. We also identified 210 odorant-degradation related genes (including sex pheromone-degradation related genes) from seven major enzyme groups. Among these genes, 100 genes are new identified and two aldehyde oxidases (AOXs), one aldehyde dehydrogenase (ALDH), five carboxyl/cholinesterases (CCEs), five UDP-glycosyltransferases (UGTs), eight cytochrome P450 (CYP) and three glutathione S-transferases (GSTs) displayed more robust expression in the antennae, and thus are proposed to participate in the degradation of sex pheromone components and plant volatiles.ConclusionsTo date, this is the most comprehensive gene data set of sex pheromone biosynthesis and degradation enzyme related genes in DBM created by genome- and transcriptome-wide identification, characterization and expression profiling. Our findings provide a basis to better understand the function of genes with tissue enriched expression. The results also provide information on the genes involved in sex pheromone biosynthesis and degradation, and may be useful to identify potential gene targets for pest control strategies by disrupting the insect-insect communication using pheromone-based behavioral antagonists.

Morphology of the adult male and pupal exuviae of Glyptotendipes (Glyptotendipes) glaucus (Meigen 1818) (Diptera, Chironomidae) using scanning electron microscope (SEM).

In this paper, a study of the morphology of the pupa and male imago of Glyptotendipes (G.) glaucus (Meigen 1818) was carried out, with the aid of a scanning electron microscope (SEM). The SEM provided additional valuable information on the morphology of the species. Adult male head, antenna, wing, leg, abdomen, hypopygium, pupal cephalothorax and abdomen were examined. It is emphasized that SEM was not often used in Chironomidae studies. The present results confirm SEM as a suitable approach in carrying out morphological and taxonomical descriptions of Chironomidae species.

The systematics of land crabs of the genus Gecarcoidea and recognition of a pseudocryptic species, G. humei, from the eastern Indian Ocean (Crustacea : Decapoda : Gecarcinidae)

The gecarcinid genus Gecarcoidea H. Milne Edwards, 1837 is currently represented by two species from the Indo-West Pacific – the widely distributed purple land crab, G. lalandii H. Milne Edwards, 1837, and the red crab endemic to Christmas Island, G. natalis (Pocock, 1889). One species, G. humei (Wood-Mason, 1874), described from the Nicobar Islands, has had a confused taxonomic history, but was treated as a junior synonym of G. lalandii by Türkay (1974) in his revision of the family. In this study, using molecular as well as morphological characters, we show that G. humei is a valid species. Gecarcoidea lalandii and G. humei have distinct non-overlapping distributions throughout much of their range, with G. lalandii occurring in most of South-east Asia and the West Pacific, while G. humei is known only from the eastern Indian Ocean. On Christmas Island, in the eastern Indian Ocean, however, all three species are present. As a result, Christmas Island is the only locality where all extant species of Gecarcoidea are found. The three species can also be separated by differences in live colours and patterns, as well as proportions of the carapace, male abdomen, ambulatory legs and third maxillipeds, and details of the orbits and male first gonopods.

Redescription of Potamonautes walderi (Colosi, 1924) from the lower Congo River basin in Central Africa (Brachyura, Potamoidea, Potamonautidae)

Potamonautes walderi (Colosi, 1924), is redescribed from the lectotype and the male gonopods, abdomen, mouthparts, chelipeds, and sternum are illustrated. Photographs of the lectotype are provided and its distribution and conservation status is discussed. Potamonautes walderi is also compared to the other species of this genus that are found in the Congo River basin in Central Africa.

Studies on reproductive efficiency and biometric parameters of progeny adults of Nesolynx thymus (Girault) (Hymenoptera: Eulophidae) – a parasitoid of Exorista bombycis (louis) (Diptera: Tachinidae) subjected to higher temperature

Of the various factors, which influence the developmental characteristics of the parasitoid, the occurrence of high degree of sensitivity to temperature among the parasitoid is considered to be one of the drawbacks in biological control programmes of the pests using parasitoids. In the backdrop of this, initially, an attempt was made know whether Nesolynx thymus an indigenous, gregarious ecto-pupal parasitoid, would complete its life cycle at temperatures between 30 and 35°C. Later at the upper vital temperature limit for development, the female parasitoid was maintained for 10 generations to induce temperature tolerance. It was observed that the parasitoid could successfully complete its life cycle upto 32°C. No significant decline in rate of parasitization was observed upto 8th generation. Though there was no consistency in the progeny production at different generation, some decline was observed from 8th generation onwards. While, the parasitoid sex ratio remained unchanged. Further, The study was continued for 10 generations and the biometric characters 1 to 10 generations an increase in the body length, head width, wingspan of male and female and abdomen width and length of females. However, in the initial 5 generations, these parameters were significantly lower compare to control and thereafter, subsequent generations, they are significantly higher over the control. The results are discussed in relation to the induction of temperature tolerance in N. thymus and stabilization in the parasitoid progeny production.