Male Pupa Research Articles

A new member of the Stictochironomus caffrarius group from West Bengal, India, with emendation of generic diagnosis (Diptera, Chironomidae).

Stictochironomus bengalensis n. sp. is described based on the male adult, pupa and larva from West Bengal, India. The species is a new member of the S. caffrarius group. Generic diagnoses for the pupa and larva are emended to accommodate the characteristics of the species group. In addition, a key to the known males of Stictochironomus from the Oriental region is provided.

Identification and Characterization of the Masculinizing Function of the Helicoverpa armigera Masc Gene

The Masculinizer (Masc) gene has been known to control sex development and dosage compensation in lepidopterans. However, it remains unclear whether its ortholog exists and plays the same roles in distantly related lepidopterans such as Helicoverpa armigera. To address this question, we cloned Masc from H. armigera (HaMasc), which contains all essential functional domains of BmMasc, albeit with less than 30% amino acid sequence identity with BmMasc. Genomic PCR and qPCR analyses showed that HaMasc is a Z chromosome-linked gene since its genomic content in males (ZZ) was two times greater than that in females (ZW). RT-PCR and RT-qPCR analyses revealed that HaMasc expression was sex- and stage-biased, with significantly more transcripts in males and eggs than in females and other stages. Transfection of a mixture of three siRNAs of HaMasc into a male embryonic cell line of H. armigera led to the appearance of female-specific mRNA splicing isoforms of H. armigera doublesex (Hadsx), a downstream target gene of HaMasc in the H. armigera sex determination pathway. The knockdown of HaMasc, starting from the third instar larvae resulted in a shift of Hadsx splicing from male to female isoforms, smaller male pupa and testes, fewer but larger/longer spermatocytes and sperm bundles, delayed pupation and internal fusion of the testes and follicles. These data demonstrate that HaMasc functions as a masculinizing gene in the H. armigera sex-determination cascade.

The genetic adaptations of fall armyworm Spodoptera frugiperda facilitated its rapid global dispersal and invasion.

The fall armyworm (Spodoptera frugiperda) is a lepidopteran insect pest that causes huge economic losses. This notorious insect pest has rapidly spread over the world in the past few years. However, the mechanisms of rapid dispersal are not well understood. Here, we report a chromosome-level assembled genome of the fall armyworm, named the ZJ-version, using PacBio and Hi-C technology. The sequenced individual was a female collected from the Zhejiang province of China and had high heterozygosity. The assembled genome size of ZJ-version was 486Mb, containing 361 contigs with an N50 of 1.13Mb. Hi-C scaffolding further assembled the genome into 31 chromosomes and a portion of W chromosome, representing 97.4% of all contigs and resulted in a chromosome-level genome with scaffold N50 of 16.3Mb. The sex chromosomes were identified by genome resequencing of a single male pupa and a single female pupa. About 28% of the genome was annotated as repeat sequences, and 22,623 protein-coding genes were identified. Comparative genomics revealed the expansion of the detoxification-associated gene families, chemoreception-associated gene families, nutrition metabolism and transport system gene families in the fall armyworm. Transcriptomic and phylogenetic analyses focused on these gene families revealed the potential roles of the genes in polyphagia and invasion of fall armyworm. The high-quality of the fall armyworm genome provides an important genomic resource for further explorations of the mechanisms of polyphagia and insecticide resistance, as well as for pest management of fall armyworm.

Morphological traits for sex identification of the oriental armyworm, Mythimna separata (Lepidoptera: Noctuidae)

The oriental armyworm, Mythimna separata (Lepidoptera: Noctuidae) is a harmful pest which causes heavy loss in agricultural crops. Sex identification of M. separata is very important for understanding the biology and management of this pest. Development of fast and convenient methods to identify M. separata female and male is the necessary prerequisite for conducting gender-related studies. In this study, new methods to differentiate sex of M. separata at pupal and adult stages were investigated. Our results showed that posterior abdominal segments containing genital organs which are morphological traits to differentiate female and male. Genital openings are important characters for the female and male pupae differentiation. For female pupa, it locates on the ventral side of eighth and ninth abdominal segments and appears as a visible longitudinal suture; for male pupa, it locates on the ventral side of the ninth abdominal segment and appears as a short slit surrounded by a pair of visible semicircular lumps. Bristle numbers are another indicator for sex differentiation of adults. Each female has three-bristled frenulum and each male has one bristled-frenulum near the base of hind wing of each side of moth body. We confirmed the two sex differentiation methods manually by dissecting genitalia of adults and found their genger was as same as what we examined the sex of pupae and adults using the morphological methods.

A new species of armored scale, Fiorinia yongxingensis (Hemiptera: Coccomorpha: Diaspididae) from Hainan Province, China.

The adult female, adult male and all immature stages (except the male prepupa and pupa) of a new species of Fiorinia (Hemiptera: Coccomorpha: Diaspididae), F. yongxingensis Liu, Cai Feng sp. n., collected from Hainan Province, China, are described and illustrated. A key is provided to identify the Fiorinia species known to occur in Hainan Province, China. The new species may become a significant pest on coconut palms.

Gender associated morphological differences in Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae)

The sexual dimorphism in pupal and adult stages of rice moth, Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) was studied. Distinct slit on eighth abdominal segment is present in female pupa, while it absent in male pupa. Female moths have longer and snout- like palpi and male moth has shorter and blunt labial palpi.

The biology of Sesamia inferens (Walker) (Lepidoptera: Noctuidae) on maize in the north western plains of India

The biology of Sesamia inferens (Walker) was studied at 25±1 °C and 70±5 per cent relative humidity on PMH 1 maize hybrid. The incubation period was 6.82±0.05 days. There were six larval instars and the larval development was completed in 29.95±0.16 days. The duration of instars I-VI was 4.17±0.09, 3.60±0.08, 4.47±0.02, 4.40±0.03, 6.18±0.06 and 7.13±0.05 days, respectively. The pre-pupal period was 2.83±0.02 days. The male and female pupa had duration of 8.05±0.12 days and 10.33±0.16 days, respectively. The adult emergence was 93.02±0.01 per cent, with a sex ratio of 1:1.05. The males had shorter longevity of 3.92±0.23 days, while females had 5.05±0.28 days. The pre-oviposition, oviposition and post-oviposition period was 1.11±0.10, 2.96±0.19 and 0.79±0.10 days, respectively. The fecundity was 211.92 ±11.92 eggs with 53.69±10.78 eggs per cluster. The egg hatchability was 92.19±0.01 per cent. The total life cycle was completed in 47.65±0.24 days (Male) and 49.93±0.21 days (female). The observations on the biology will help in developing efficient strategies to manage S. inferens on maize in the north western plains of India.

Description of the adult male, larva and pupa of Topomyia (Topomyia) aureoventer (Diptera: Culicidae) in India.

The original description of Topomyia aureoventer by Theobald (1910) included only the adult female. Description of the adult male, pupa and larva, with figures of the male genitalia, pupa and larva, are provided. The larva is predacious with well-developed mandibles and inhabits leaf axils of Colocasia plants.

Taxonomic review of Ablabesmyia Johannsen (Diptera: Chironomidae: Tanypodinae) from Oriental China, with descriptions of six new species.

Six new species of the genus Ablabesmyia are described and illustrated from Oriental China: A. (Ablabesmyia) lyrata sp. n. and A. (Ablabesmyia) pectinata sp. n. each based on the male adult and pupa; and A. (Ablabesmyia) huananensis sp. n., A. (Ablabesmyia) praegracilis sp. n., A. (Ablabesmyia) bifurca sp. n. and A. (Karelia) daiensis sp. n. each based on the male adult. The subgenus Karelia is recorded from China for the first time. In addition, A. (Ablabesmyia) alba Chaudhuri, Debnath et Nandi and A. (Ablabesmyia) maculitibialis Chaudhuri, Debnath et Nandi are redescribed based on the male adult, and new distribution records are given for A. (Ablabesmyia) prorasha Kobayashi et Kubota, A. (Ablabesmyia) amamisimplex Sasa and A. (Ablabesmyia) jogancornua Sasa et Okazawa.

The functional difference of eight chitinase genes between male and female of the cotton mealybug, Phenacoccus solenopsis.

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is a polyphagous insect that attacks tens of plant and causes substantial economic loss. Insect chitinases are required to remove the old cuticle to allow for continued growth and development. Though insect chitinases have been well studied in tens of insects, their functions in mealybug are still not addressed. Here, we sequenced the transcriptomes of adult males and females, from which eight chitinase genes were identified. We then used the method of rapid amplification of cDNA ends to amplify their full length. Phylogenetic analysis indicated that these genes clustered into five subgroups. Among which, groupII PsCht2 had the longest transcript and was highly expressed at second instar nymph. PsCht10, PsCht3-3 and PsIDGF were highly expressed in the adult females, whereas PsCht4 and PsCht4-1 were significantly expressed at the male pupa and adult male. Next, we knocked down all eight chitinase genes by feeding the double-stranded RNA. Knockdown of PsCht4 or PsCht4-1 led to the failure of moult and, silencing PsCht5 resulted in pupation defect, while silencing PsCht10 led to small body size, suggesting these genes have essential roles in development and can be used as a potential target for pest control.

New data on taxonomy and systematics of the genus Diamesa Meigen (Diptera: Chironomidae: Diamesinae) from Tien Shan and Pamir Mountains, with description of two new species

An illustrated morphological description of two new species of the genus Diamesa Meigen, 1835 are provided from Tien Shan and Pamir mountains: D. akhrorovi sp. nov., as male adult; D. alibaevae sp. nov., as male adult and pupa. DNA barcoding results of the two new described species with comparative database on some related Diamesa species are also given. The two new described species key both near D. planistyla Reiss, 1968, which was known from Nepal and redescribed here from Tian Shan. The diversity of Diamesa genus using three mitochondrial (COI, COII, 16S rRNA), two nuclear (18S rRNA, EF-1a) markers and estimating phylogenetic relationships is also highlighted. Six of the studied Diamesa species including D. akhrorovi sp. nov. and D. alibaevae sp. nov. represent a well-supported monophyletic clades with high Bayesian posterior probability, while D. cinerella Meigen and D. hamaticornis Kieffer have a lower interspecific sequence divergence.

Description of a new species of Hemiberlesia Cockerell (Hemiptera: Coccomorpha: Diaspididae) from China, with a key to Hemiberlesia species known from China.

The diagnostic characters of the genus Hemiberlesia Cockerell (Hemiptera: Coccoidea: Diaspididae) are reviewed. The adult female, adult male and all immature stages (except the male prepupa and pupa) of a new species, H. serrulata Liu Feng sp. n., collected from Henan Province, China, are described and illustrated. A key is provided to identify the Hemiberlesia species known to occur in China.

Chaetocladius coppai sp. nov. and C. diai sp. nov., two mountain species inhabiting glacial springs and cold streams of the Alps and Lebanon (Diptera: Chironomidae, Orthocladiinae)

Two new species of the genus Chaetocladius are described, C. (s. str.) coppai sp. nov. as male adult and C. (s. str.) diai sp. nov. as male adult and pupa. The descriptions are based on the material collected at glacial alpine springs and small streams located in the Maritime French Alps and the Swiss Alps for C. coppai sp. nov., and the Mount Lebanon range for C. diai sp. nov. According to the characters of the adult males, C. coppai sp. nov. belongs to the laminatus-group, while C. diai sp. nov. is close to C. elegans Makarchenko et Makarchenko, 2001. The comments on the taxonomic position, ecology and geographical distribution of the new species are given.

The Diatraea Complex (Lepidoptera: Crambidae) in Colombia's Cauca River Valley: Making a Case for the Geographically Localized Approach.

The sugarcane stem borers Diatraea saccharalis (Fabricius) and D. indigenella Dyar & Heinrich are common pests of sugarcane crops in Colombia's Cauca river valley (CRV). In 2012, however, D. tabernella Dyar was recorded for the first time in northern CRV and just 1year later, D. busckella Dyar & Heinrich was detected, also for the first time, in central CRV. The Diatraea outbreak in the CRV was studied, its distribution and population in the region was analyzed, and levels of larval parasitism were observed. During the study of the outbreak, Diatraea species in the CRV were characterized based on the morphology of larval, pupal, and adult stages. Keys to the identification of Diatraea in the CRV based on male genitalia and pupa are provided. Pupal cephalic horns and lateral lobes were discovered as new, reliable characteristics to separate the species at the pupal stage. We suggest biological control program modifications to decrease economic impact and studies at geographically localized levels to better understand the dynamics between the pest species and their parasitoids.

A new species of Polypedilum Kieffer, 1912 (Diptera: Chironomidae) from India

Life stages of Polypedilum (Polypedilum) aduncum sp. nov. is described and illustrated as male imago, pupa and larva from India.http://www.zoobank.org/urn:lsid:zoobank.org:pub:C5978143‐1540‐4565‐B81C‐12E30E299AC4

Impact of microsporidian infection on growth and development of silkworm Bombyx mori L. (Lepidoptera: Bombycidae)

Several species and strains of microsporidia have been isolated from infected silkworms among which pebrine caused by Nosema bombycis Nageli is the most important. Infection from this disease causes severe economic loss in sericulture. Reduction of larval and pupal development and reduced weights in silkworms due to infection has been reported. In the present study, five microsporidian (Nosema) isolates from mulberry silkworm, Bombyx mori L. collected from different locations in West Bengal, India were sampled to study the impact of their infection on the growth and development of B. mori. The study revealed significant differences among the isolates in their ability to cause a reduction in the larval and pupal development of silkworm. Healthy larvae showed better body and tissue weights which were significantly higher than in infected lots. Among the isolates, M5 registered the maximum reduction in relative growth rate, larval silk gland tissue somatic index, larval male and female gonad tissue somatic index (GTSI) and pupal female GTSI compared to the healthy control. Male and female pupa treated with M5 spores died before emergence, suggesting that the M5 isolate was the most virulent.

Description of a new species of the genus Hulecoeteomyia (Diptera: Culicidae) from Meghalaya, India.

Female and male adults, female and male genitalia, pupa and larva of Hulecoeteomyia cherrapunjiensis, a new mosquito species, are described from Meghalaya, India. Keys to separate larvae and adults are provided.

Two species of Nilothauma Kieffer (Diptera, Chironomidae) from Japan,with description of a new species.

The male and female adults and pupa of Nilothauma niidaense n. sp. are described and illustrated on the basis of the material collected from a fontal stream in Fukushima Prefecture, Japan. N. sasai Adam & Sæther is treated as a junior synonym of N. hibaratertium Sasa, of which the male is redescribed. The Adam & Sæther key to Nilothauma males is revised.

Effect of female vs. male pupa of Scirpophaga excerptalis Walker on reproductive potential of Tetrastichus howardi (Olliff) (Hynenoptera: Eulophidae)

Tetrastichus howardi (Olliff) (Eulophidae: Hymenoptera) is gregarious and polyphagous endopupal parasitoid associated with sugarcane stem borers. It is adapted in its host-searching strategy to penetrate tunnels excavated by stem borers which is a prerequisite for a good biological control agent of stem borers. The experiment was conducted at 25 ± 2°C and 65 ± 5% relative humidity in BOD with ten replications at Biological in Division of Crop Protection, ICAR, Lucknow. The number of adult emerged (81.29) from female pupa (81.29) was more than male pupa (65.30). The smaller host pupae (i.e. male pupa) gave rise to small number of parasitoids whereas larger ones (i.e. female pupa) supported development of more parasitoids. The parasitoid completed development in 19.5 days on both pupae. There was no significant difference of development period in male vs. female pupa. The female emergence (%) on female and male pupa was 86.94 and 74.23, respectively. The number and sex ratio of adult progeny emerging from host pupa depends on the size. The large host size is more beneficial to the fitness of daughters than to sons and selection would then favor wasps to lay more daughters in large hosts and more sons in small hosts. It is concluded that parasitoid had high reproductive potential, more female biasesd sex ratio and its gregarious development make possible to multiply on sugarcane top borer in the laboratory.

New species and records of Goeldichironomus Fittkau, 1965 from Brazil(Diptera: Chironomidae).

One new species named Goeldichironomus adhaerens sp. n. is described from urban area in Manaus, Brazilian Amazon, based on male adult, pupa and larva. New records of G. neopictus Trivinho-Strixino & Strixino, G. maculatus Trivinho-Strixino & Strixino, G. pictus Reiss and G. fluctuans Reiss are also provided.