刘氏蝎蛉卵巢管结构和卵子发生（英文）

卵巢管结构及卵子发生过程在探讨昆虫系统发育关系中有重要意义, 深入研究长翅目昆虫卵巢管结构及卵子发生可为确定其在全变态类昆虫中的系统发育地位提供依据。本文利用光学显微镜和扫描、透射电子显微镜技术研究了刘氏蝎蛉Panorpa liui Hua卵巢管超微结构及卵子发生过程。结果表明：蝎蛉卵巢由12根多滋式卵巢小管组成, 每个卵巢小管分为端丝、生殖区和生长区。根据滋养细胞、卵母细胞及滤泡细胞的变化, 卵子发生过程可分为5个阶段：卵黄发生前早期、卵黄发生前中期、卵黄发生前后期、卵黄发生期及卵壳形成期。在卵黄发生期, 滋养细胞为卵母细胞提供养分后逐渐消亡, 而此时的卵母细胞可通过滤泡之间的细胞间隙从血淋巴中获取营养。在卵壳形成期间, 3种不同类型的滤泡细胞参与形成不同区域的卵壳, 从而形成不同花饰的卵壳表面。据此推测, 与其他目的滋养细胞数目相比, 每个卵室中2次有丝分裂形成3个滋养细胞可能是比较原始的特征, 表明长翅目昆虫可能是全变态类群中近基部的分支。     

A new species of Corydalus Latreille from Venezuela (Megaloptera, Corydalidae)

A new species of dobsonfly, Corydalus wanningeri, from Venezuela, is described and illustrated. It superficially resembles Corydalus neblinensis Contreras-Ramos, with a uniform reddish coloration of body and wings. Yet, because of male genitalic structure it might be closely related to Corydalus crossi Contreras-Ramos. Specimens were collected from a rain forest transitional zone between the Orinoco lowlands and the Gran Sabana plateau, in Bolívar state. This is the 15(th) species of Corydalus to be recorded from Venezuela, rendering this the country with the highest number of documented Corydalus species. A key to the sexually dimorphic, long-mandibled Venezuelan species of the genus is provided.     

Phylogenetic review of the Chinese species of Acanthacorydalis (Megaloptera, Corydalidae)

The dobsonfly genus Acanthacorydalis Weele is a small genus which only occurs in Asia and comprises eight species. Seven species are restricted to the Oriental realm, while A. orientalis (McLachlan) extends into the Palaearctic realm. There are five species in China, four of which are endemic. In the present paper, the Chinese species are redescribed, illustrated, keyed, and subjected to phylogenetic and biogeographical analyses for the first time. Geographic distributions are updated. The cladistic analysis for the Chinese species was constructed by using Hennig86, based on 17 adult morphological characters. The phylogenetic relationships obtained are ( A. orientalis + A. yunnanensis + A. unimaculata + ( A. fruhstorferi + A. sinensis )). Six areas of endemism are identified based on Acanthacorydalis distributions: north, south-west, central and south China, north-eastern India and northern Vietnam.     

Structure of the ovaries and oogenesis in Cixius nervosus (Cixiidae), Javesella pellucida and Conomelus anceps (Delphacidae) (Insecta, Hemiptera, Fulgoromorpha)

Ovary organization in representatives of two families of Fulgoromorpha, Cixiidae (Cixius nervosus) and Delphacidae (Javesella pellucida and Conomelus anceps), was examined by light and transmission electron microscopy. Ovaries of studied fulgoromorphans consist of telotrophic ovarioles. From apex to base individual ovarioles have four well defined regions: a terminal filament, tropharium (trophic chamber), vitellarium and pedicel (ovariolar stalk). Tropharia are not differentiated into distinct zones and consist of syncytial lobes containing multiple trophocyte nuclei embedded in a common cytoplasm. Lobes are radially arranged around a branched, cell-free trophic core. Early previtellogenic (arrested) oocytes and prefollicular cells are located at the base of the tropharium. The vitellarium houses linearly arranged developing oocytes each of which is connected to the trophic core by a broad nutritive cord. Each oocyte is surrounded by a single layer of follicular cells that become binucleate at the beginning of vitellogenesis.     

Revision of the fishfly genus Ctenochauliodes van der Weele (Megaloptera, Corydalidae)

The first taxonomic revision and phylogenetic analysis of the Oriental fishfly genus Ctenochauliodes van der Weele, 1909 is presented. Except for C. punctulatus , where the male is unknown, all species of Ctenochauliodes and two outgroups ( Archichauliodes chilensis Kimmins and Protochauliodes bullocki Flint) were scored for 24 adult morphological characters, 21 of which were obtained from the male genitalia. The monophyly of Ctenochauliodes is corroborated by a series of synapomorphic characters. The pectinate female antenna was proposed as a diagnostic character. Two main clades within Ctenochauliodes were found based on the present phylogenetic analysis. All 12 Ctenochauliodes species are keyed, described and illustrated, with five species new to science. Ctenochauliodes forcipatus Kimmins is a junior synonym of C. friedrichi Navás, and C. moganshanus Yang & Yang is a junior synonym of C. griseus Yang & Yang. All Ctenochauliodes species were recorded from southern China, including 11 endemic species. Hence, there is no doubt that southern China should be acknowledged as the distribution centre of Ctenochauliodes .     

Sequencing and analysis of the complete mitochondrial genome of the giant dobsonfly Acanthacorydalis orientalis(McLachlan)(Insecta:Megaloptera:Corydalidae)

The complete mitochondrial genome of Acanthacorydalis orientalis(McLachlan)was determined and analyzed(GenBank accession number:KF840564).This paper represents the first mitochondrial(mt) genome of the dobsonfly genus Acanthacorydalis.The mt genome is a typical circular DNA of 15 753 bp composed of 37 genes with an A+T content of 76.7%.It has an ancestral gene arrangement of the insect mt genomes.Eleven of the 13 PCGs start with codon ATT and ATG,while several exceptions such as ATA and TTG respectively for atpS and nad\ are also present.Five protein-coding genes end with a single T,while others have a termination codon of TAA or TAG.Most tRNAs are folded into the typical clover-leaf structure except for the trnS 1 whose dihydrouridine arm was a simple loop.The secondary structure of rrnl consists of five structural domains and 50 helices,while the rrns includes three domains and 34 helices.The control region has a stretches of Ts with a length of 22 bp but lacks obvious tandem repeat region.Both Bayesian inference and maximum likelihood(ML) analyses,based on all 13 protein-coding genes and two rRNA genes of the mt genomes,confirm the monophyly of Corydalinae and suggest that Acanthacorydalis,together with Corydalus,which is an endemic dobsonfly genus from the New World,belong to a monophyletic lineage.     

Intra- and interspecific variation in body size ofProtohermes (Megaloptera: Corydalidae)

The life history of three populations ofProtohermes grandis and two populations ofProtohermes immaculatus (Megaloptera: Corydalidae) was compared. In general, the larvae lived in stream riffles for 2 years and the adults appeared in summer. Adult body size differed between these closely related species and also between the populations ofP. grandis. Dwarfism occurred inP. immaculatus, a species that is endemic to the small, isolated island, Amami Island. The population ofP. grandis on Yaku Island, located between Amami Island and the mainland Kyushu, had an intermediate body size between that ofP. immaculatus and the mainland population ofP. grandis. Despite being an insular population,P. grandis on Tsushima Island had a similar body size to mainlandP. grandis. In these populations with large adults, some larvae lived in the streams for 3 years. The size distribution of benthic animals, which are the prey available toProtohermes larvae, differed between the streams studied. The density of large prey was lowest on Amami Island, intermediate on Yaku Island, and highest on the mainland and Tsushima Island. Different size distributions of available prey may be caused by the differences of benthic fauna; most of Ecdyonuridae and Ephemerellidae (large mayflies) and Perlidae (large stoneflies) were not found on Amami and Yaku Islands. Thus, there is a tendency to dwarfism in the populations ofProtobermes inhabiting streams where the density of large prey is low.     

Distribution of cytoskeletal elements in the ovarioles of Mutilla sp. (Insecta,Hymenoptera)

The ovaries of Mutilla sp., as those of other hymenopterans, consist of meroistic-polytrophic ovarioles. Within each ovariole, a terminal filament, a germarium, and a vitellarium can be distinguished. The germaria contain numerous dividing and/or differentiating groups (clusters) of germ cells. The vitellaria are composed of several, linearly arranged, ovarian follicles; each follicle consists of an oocyte and a group of nurse cells. Distribution of cytoskeletal elements (microfilaments and microtubules) throughout the ovarioles of Mutilla sp. has been studied on whole mount preparations stained with rhodamine-conjugated phalloidin and FITC-labelled anti-tubulin.     

A revision of the genus Neoneuromus in China (Megaloptera: Corydalidae)

Lake Illawarra, is a typical shallow intertidal coastal barrier lagoon in New South Wales, Australia. This paper reports the first examination of photosynthetic characteristics of benthic microalgae and seagrass in this lake by measuring the oxygen exchange procedure (flux) using sediment-core incubations in the laboratory. Photosynthesis vs irradiance relationships (P–I curves) were generated from measurements made at nine irradiances for microphytobenthos (MPB) at five different water depths (sites) during September 2002. Maximum benthic gross primary production (GP_max) for MPB in this lake tended to decrease with the increasing water depth from Site 5 (about 0.2 m deep) to Site 1 (about 3.0 m deep), and was correlated with decreasing surface sediment Chl-a concentrations.     

Radio tracking and activity monitoring of the dobsonfly larva,Protohermes grandis (Megaloptera: Corydalidae)

Summary A miniature crystal-controlled radio transmitter, 7x17x2 mm³ and 185 mg in water, was attached to the back of prothorax of individual dobsonfly larvae, Protohermes grandis. Positions of these larvae in the stream bed were determined using a loop antenna, and they were tracked for 19 days. Actograms were also taken by recording the frequency variation of transmitting signals which were changed according to the larval posture. Larvae changed their positions in the stream bed in some nights, but never in the daytime. However, in most nights (92.7%), they continued to stay at the same position. Actograms revealed that larvae were quite motionless in most time (90.8% of daytime and 89.7% of night). Thus, larvae use the ambush mode of foraging in the central part of riffles where prey are continuously redistributed and sufficient oxygen is supplied with a water current.     

Seasonal change in the respiration of the dobsonfly larva, Protohermes grandis(Megaloptera: Corydalidae)

SUMMARY 1. Seasonal change in the respiration of the dobsonfly larva, Protohermes grandis ,was studied by measuring the oxygen consumption rate (resting metabolism) bimonthly for 2 years. The respiratory rate of the larva was significantly lower during the summer season when the stream temperature rose to 30°C.
2. Summer depression of respiration was confirmed by measuring the rate of carbon dioxide evolution. The mean value of the respiratory quotient was estimated to be 0.76 ± 0.05 SE. The larva is believed to conserve energy by this reduction in respiratory rate,
3. In other seasons, however, the larva maintained a higher respiratory rate and remained active even in the winter when the stream temperature decreased near to 0°C. In fact, significant growth in weight occurred from mid-October to late March.
4. This acclimation to temperature may enable the efficient allocation of energy during the long larval period (3 years) in streams which have large annual fluctuations in temperature.     

Ejaculate production schedule and the degree of protandry in fishflies (Megaloptera: Corydalidae)

1. To examine the relationship between male–female emergence patterns and ejaculate dynamics, patterns producing sperm and seminal fluids in male internal reproductive organs, the size of a spermatophore transferred at mating and the fate of spermatophore contents moved into female storage organs were compared among the fishflies (Megaloptera: Corydalidae: Chauliodinae), Parachauliodes continentalis, P. japonicus and Neochauliodes sinensis .
2. Spermatophore contents moved into female storage organs decreased rapidly in P. japonicus and N. sinensis , but hardly at all in P. continentalis . This suggests that the females of the former two species may remate sooner than the latter species as it is known in insects that material remaining in the storage organs mechanically inhibits receptivity to mating.
3. Male P. japonicus and N. sinensis increased in internal reproductive organ mass continuously after adult eclosion, and the spermatophore size produced at the first mating increased with male age. In contrast, the internal reproductive organs of P. continentalis were relatively small and did not increase in mass after emergence. P. continentalis transferred a constantly smaller spermatophore at any copulation than the former two species.
4. Males of P. japonicus and N. sinensis emerged earlier than females, while P. continentalis showed a nearly simultaneous emergence pattern between the sexes. It seems that males of P. japonicus and N. sinensis (more polyandrous than P. continentalis ) inhibit female receptivity for a longer time period by emerging earlier and transferring larger ejaculates. In these two species, the number of sperm ejaculated at the first mating also increased with male age. The increase in sperm number by emerging earlier may be adaptive for the males owing to numerical sperm competition when the female remates.     

Systematics of the Protohermes xanthodes species-group in eastern Asia (Megaloptera: Corydalidae)

A new species‐group of the dobsonfly genus Protohermes is proposed, the Protohermes xanthodes species‐group. Three species from eastern Asia belonging to the new species‐group are redescribed and illustrated. Phylogenetic relationships among the species in this group, as well as the biogeography of these species, are discussed on the basis of a cladistic analysis.     

Phylogeography of postglacial range expansion in Nigronia serricornis Say (Megaloptera: Corydalidae)

We have examined the effects of post-Wisconsinan glacial range expansion on the phylogeography of the saw-combed fishfly, Nigronia serricornis Say (Megaloptera: Corydalidae) because aquatic insects are under-represented in postglacial studies (and in phylogeography in general), and because the effects of ecological degradation on the population genetics of environmental indicator species like N. serricornis cannot be measured unless the underlying phylogeography is understood. Sequence data from a 630-base fragment of the mitochondrial cytochrome oxidase I (COI) gene were subjected to amova and nested clade analysis for 30 populations (n = 344) of N. serricornis. Both the amova and nested clade analysis revealed substantial population structure; 44.4% of the variance occured among populations. Three northward migrations are apparent: one from Tennessee into Illinois, Indiana, Wisconsin, Michigan and Ontario, a second that radiated eastward from Pennsylvania, and a third that moved along the coast from North Carolina into Connecticut, Massachusetts, Maine and then into New York. The latter two of these migrations were the result of contiguous range expansions, while the former expansion, out of Tennessee, appears to have been rapid with little gene flow from the source population. Additional clades included a group of haplotypes in central Kentucky that appear to have expanded along preglacial drainages, and clades in North Carolina and Georgia that have remained centrally located. Haplotype diversity decreased from south to north, a pattern that has been widely reported for animal and plant populations that expanded with the retreat of the Wisconsinan glaciation.     

Structural and functional dynamics of oogenesis in Glossina austeni: general features, previtellogenesis and nurse cells.

Glossina austeni oogenesis throughout its nine-day pregnancy cycle is described with the focus on previtellogenic stages. The ultrastructural details of the oocyte-nurse cell relationship and cyst formation is presented. The oocyte develops in a syncytial association with 15 nurse cells with the entire unit surrounded by a follicular epithelium. The nurse cells have large elaborate nucleoli. Evidence of nuclear emissions and the presence of an unusual cytoplasmic membrane association were found. A variety of nuclear inclusions are seen in the oocyte. Glycogen, lipid, ribosomes and membrane organelles accumulate in the oocyte during previtellogenesis.     

Life history variation in a dobsonfly, Protohermes grandis (Megaloptera: Corydalidae): effects of prey availability and temperature

SUMMARY. 1. The life cycle of a predatory insect, Protohermes grandis (Megaloptera: Corydalidae), was compared in four streams in central Japan. The effects of annual temperature regime and prey availability on life history characteristics were also assessed.
2. The larval period was 2 years and small adults emerged in the Morito River, where summer water temperature was high and large prey scarce.
3. In the Nagura River, rich in large prey, the larval period was also 2 years in spite of slightly lower temperature, and the adult size was largest among the streams.
4. In Anado Fork with a low summer temperature, the larval development took 3 years, and large adults emerged. Large prey were abundant in this stream.
5. Seasonal abundance of large prey also affected the time large larvae left the stream to pupate. Larvae emigrated earlier in streams where the density of large prey sharply decreased after spring, than in streams where large prey were available throughout the year.     

Structure and development of ovaries in the weevil, Anthonomus pomorum (Coleoptera, Polyphaga). I. Somatic tissues of the trophic chamber

In developing ovarioles of Anthonomus pomorum (Coleoptera, Polyphaga, Curculionidae) the trophic chambers (tropharia) are relatively large and consist of clusters (clones) of germ cells and various somatic tissues. Each ovariole is enclosed within an outer epithelial sheath (tunica externa). Throughout the pupal phase, the growth of this sheath is accelerated and precedes the development of the rest of the ovariole. As a result, the epithelial sheath proliferates anteriorly and forms an elongated "sleeve" that during the later stages of development becomes gradually filled by the growing tropharium. In the early pupal stage, a few terminal filament cells are observed in contact with the anterior end of the tropharium. These cells are separated from the rest of the trophic chamber by a transverse septum, which maintains continuity with the basal lamina. Beneath the basal lamina there is a layer of inner sheath cells, whereas inside the tropharium there are interstitial cells. These two types of cell differ morphologically in a mature ovary but they retain, until the end of the imago-B stage, a similar ultrastructure testifying to their common origin. At the posterior end of the tropharium, from the imago-B stage on, many young oocytes, surrounded by prefollicular cells, are observed. This is the so-called neck region of the tropharium. Extraction with Triton X-100 detergent showed that in a mature trophic chamber there are only individual microtubules arranged along the projections of interstitial cells. This indicates that the cytoskeleton elements (microfilaments and microtubules) participate only to a very limited extent in the spatial organisation of the tropharium in A. pomorum.     

Global diversity of dobsonflies,fishflies, and alderflies (Megaloptera; Insecta) and spongillaflies,nevrorthids, and osmylids (Neuroptera; Insecta) in freshwater

The insect orders Megaloptera and Neuroptera are closely related members of the superorder Neuropterida, a relict lineage of holometabolous insects that also includes the Raphidoptera. Megaloptera, composed of the families Sialidae and Corydalidae (including subfamilies Chauliodinae and Corydalinae), has fully aquatic larvae that occur in a wide variety of lotic and lentic habitats, including temporary streams. In total, 2 of 17 families of Neuroptera have aquatic larvae: Nevrorthidae live in the benthos of fast-flowing streams and Sisyridae reside on freshwater sponges. A third family of Neuroptera, Osmylidae, contains some water-dependent species that reside under leaves and rocks along the margins of waterbodies. We recognize 328 extant, described species of Megaloptera (composed of 116 species of Chauliodinae, 131 species of Corydalinae, and 81 species of Sialidae) and 73 species of aquatic Neuroptera (composed of 12 species of Nevrorthidae and 61 species of Sisyridae). Additionally, we estimate that 45 species of Osmylidae are water-dependent, although the ecology of this group is poorly understood. Chauliodinae and Corydalidae are both found in the New World, the Oriental region, and South Africa, but are absent from Europe, the Middle East, Central Asia, tropical Africa, and boreal regions. Chauliodinae is quite speciose in Australia, whereas Corydalinae is absent. Sialidae is most speciose in temperate regions, and is absent from tropical Africa and portions of the Oriental region. Sisyridae and Osmylidae are nearly cosmopolitan, but the relict family Nevrorthidae is limited to Japan, the Mediterranean, and Australia. The discovery of many new species in recent years, particularly among Corydalidae in the Neotropics and China, suggests that our knowledge of aquatic neuropterid diversity is far from complete. Guest editors: E. V. Balian, C. Lévêque, H. Segers and K. Martens Freshwater Animal Diversity Assessment