中国海南长足寄蝇属一新种(双翅目,寄蝇科)

长足寄蝇属幼虫主要寄生于土壤中生活的金龟总科昆虫,分布于东洋区、非洲热带区和古北区,其幼虫尾节背部均具2根特征性长鬃,区别于长足寄蝇族其它属而为一单系群.记述了采自我国海南省的长足寄蝇属1新种:海南长足寄蝇Dexia hainanensis sp.nov.,与分布东洋区的异长足寄蝇Dexia divergens Walker近似,但胸部背板黑色内侧纵条较窄,雌、雄腹部第3背板均具完整的1列后缘鬃,肛尾叶较窄.新种模式标本保存在沈阳师范大学昆虫研究所.     

Ultrastructure of mediodorsal setae in biting midge larvae of the genus Atrichopogon Kieffer with notes on their biological significance (Diptera: Ceratopogonidae)

The ultrastructure of the strong mediodorsal setae in terrestrial stage IV larvae of Atrichopogon (Meloehelea) oedemerarum and A. (M.) meloesugans was examined using light, scanning and transmission electron microscopy. Serrated setae placed on prominent processes are distributed in pairs on all thoracic and abdominal segments. Setae are innervated by a single dendrite and their surface has no pores. The trichogen cell is not retracted from the setal lumen on completion of the hair-forming process but fills the mediodorsal seta also when the larval cuticle is fully sclerotised. Such a phenomenon was previously reported in terrestrial larvae of the genus Forcipomyia. We suggest that the mediodorsal setae described in Atrichopogon are plesiotypic mechanoreceptors for the subfamily Forcipomyiinae. They are preserved in the truly terrestrial larvae of Atrichopogon, but modified to secretory setae in the genus Forcipomyia. Both genera bearing distinct mediodorsal setae have developed functional tracheal gills, unknown in other biting midges.     

A revised numerical chaetotaxy for neotropical Phlebotomine sandfly larvae (Diptera: Psychodidae)

Phlebotomine larval taxonomy is briefly reviewed with particular reference to New World species, of which under one fifth have been adequately described as immature stages. A new numerical chaetotaxy is proposed following studies on the larvae of six species from Brazil. Setal numeration is used in a manner which demonstrates apparent segmental homologies and the use of letter designations for some setae has been reduced. With two exceptions the mesothoracic, metathoracic and abdominal setae are homologized with those of the posterior prothorax, and the anterior prothoracic setae are regarded as atypical.     

Tarsal attachment devices of the southern green stink bug Nezara viridula (Heteroptera: Pentatomidae)

Based on analyses with cryo‐scanning and transmission electron microscopy, the present study reports on the morphology and ultrastructure of the attachment structures of the green stinkbug Nezara viridula L. (Heteroptera: Pentatomidae), a cosmopolitan pest of different crops in most areas of the world. In addition, the presence and distribution of large proportions of the elastic protein resilin in these structures was revealed by confocal laser scanning microscopy. The attachment structures of each leg comprise two sclerotised claws, a pair of smooth flexible pulvilli and a hairy adhesive pad located at the ventral side of the basitarsus. No sexual dimorphism is evident. Contact areas of resting individuals on a smooth surface show that N. viridula creates contact to the substrate with the ventral surface of (a) the distal portions of the pulvilli, (b) the setae of the hairy adhesive pad, (c) the two paraempodia representing mechanosensory setae, and (d) the tips of the claws. Each pulvillus is a sac‐like structure formed by complex cuticular layers that vary in their structure and resilin content. The dorsal side consists of sclerotised chitinous material, while the ventral cuticle consists mainly of resilin and shows a very thin epicuticle and a thick exocuticle. The setae of the hairy adhesive pad are pointed and socketed. They exhibit a pronounced longitudinal gradient in the material composition, with large proportions of resilin being present in the setal tips. In most of these setae, especially in those of the distal‐most part of the pad, also a transverse gradient in the material composition is visible.     

Morphology and histology of secretory setae in terrestrial larvae of biting midges of the genus Forcipomyia (Diptera: Ceratopogonidae)

Apneustic larvae of the genus Forcipomyia possess unique secretory setae located on the dorsal surface along the body in two rows, one pair on each thoracic and abdominal segment and two pairs on the head. Morphological and histological studies of secretory setae in fourth instar larvae of Forcipomyia nigra (Winnertz) and Forcipomyia nigrans Remm indicate they are modified mechanoreceptors (sensilla trichodea) in which the trichogen cell is a glandular cell producing a hygroscopic secretion. The cytoplasm of the glandular trichogen cell fills the lumen of a secretory seta, which shows one or more pores on the apex. The cytoplasm contains numerous microtubules responsible for transportation of proteinaceous vesicles, and an extremely large polyploid nucleus typical of gland cells. The main role of the hygroscopic secretion is to moist the body and thus facilitate cuticular respiration.     

Setiferous structures of male coleoptera

A scanning electron microscopy study was made of the male setiferous sex patches and analogous structures in 11 families of Coleoptera (Anthribidae, Bruchidae, Ciidae, Cleridae, Coccinellidae, Dermestidae, Leiodidae, Ptinidae, Staphylinidae, Tenebrionidae, and Ostomatidae). These secondary sexual characters appear to have several features in common including relatively long, often ridged, setae, cuticular ducts (frequently cribriform pore plates), and the production of a secretion. It is suggested that these structures may all be concerned with the production, release, and dissemination of pheromones.     

Segmental mismatch in crustacean appendages: the naupliar antennal exopod of Artemia (Crustacea, Branchiopoda, Anostraca)

Based on traditional techniques and confocal laser scanning microscopy for external morphology, and immunohistochemistry for the muscular system, we describe here the segmental features of the antennal exopod of Artemia nauplii. Two kinds of serial elements are present, i.e. setae (with cuticular folds at their base) and ringlets (serially arranged sclerites separated by joint-like cuticular folds not extending to form complete rings around the appendage). The two series are usually not in register. The cuticular folds of the setae and of the ringlets are also sites of intermediate insertions of the three exopod muscles: as the two tegumentary structures are discordant in periodicity, this is also mirrored in the pattern of muscle insertions on the two sides of the appendage. Similar cases of segmental mismatch are known for the trunk of several arthropods, but segmental mismatch along the appendages has received very little attention. The occurrence of segmental mismatch in the naupliar appendages of both extant and fossil crustaceans is reviewed and it is suggested here to be a primitive feature of the exopods of both second antennae and mandibles. Problems in the interpretation of morphological evidence are discussed, also in relation to development and evolution of segmentation of naupliar appendages.     

Distinguishing features of immature stages of Panchaetothripinae (Thysanoptera: Thripidae) known in New Zealand

Diagnostic morphological characters of the juvenile Panchaetothripinae in New Zealand are illustrated. Keys developed enable colonies with only immature stages to be identified without needing to rear adults. Live larvae or larvae in ethanol are distinguished by the presence of expanded tips of body setae (Parthenothrips dracaenae), the absence of setae at the abdomen tip (Hercinothrips bicinctus), setae at abdomen tip not longer than abdominal tip width (Heliothrips haemorrhoidalis) and abdominal tip setae longer than abdominal tip width (Sigmothrips aotearoana, endemic species). The presence or absence of spine-like setae on abdominal segments 9 and 10, and the number and length of setae on the wing buds, enable identification of pupae. Abdominal spine-like setae were on the prepupa and pupa of H. bicinctus and S. aotearoana, species that pupate off the plant, and are probably defensive structures. This is the first record of spine-like setae on segment 10 of terebrantian pupae.     

The evolution of pedipalps and glandular hairs as predatory devices in harvestmen (Arachnida,Opiliones)

Pedipalps are the most versatile appendages of arachnids. They can be equipped with spines (Amblypygi), chelae (Scorpiones), or adhesive pads (Solifugae), all of which are modifications to grasp and handle fast‐moving prey. Harvestmen (Opiliones) show a high diversity of pedipalpal morphologies. Some are obviously related to prey capture, like the enlargement and heavy spination of Laniatores pedipalps. Many Dyspnoi, by contrast, exhibit thin, thread‐like pedipalps that are covered with complex glandular setae (clavate setae). These extrude viscoelastic glue that is used to immobilize prey items. Comparable setae (plumose setae) have previously been found in representatives of both Eupnoi and Dyspnoi, yet comprehensive data on their distribution are lacking. This study examined the distribution and ultrastructure of glandular setae in harvestmen and related them to pedipalpal morphology. Pedipalpal and setal characters were analysed in a phylogenetic framework. We found that glandular setae are synapomorphic for and widespread in the Palpatores clade (Eupnoi plus Dyspnoi). Their occurrence correlates with pedipalp morphology and feeding habit. Remnants of arthropod cuticular structures or secretions, frequently found attached to glandular setae, and behavioural observations, underlined the importance of the setae for capturing and securing prey. We hypothesize that glandular setae evolved as an adaptation to capture small and agile prey, which are hard to catch with a capture basket. Details of ultrastructure indicate that the setae are derived sensilla chaetica, with both a secretory and sensory function. Derived ultrastructural characters of the glandular setae, such as slit‐like channel openings and a globular arrangement of the microtrichia, may increase their effectiveness. The functional role of further pedipalpal modifications, such as apophyses, stalked and hyperbendable joints, and curved segments, as well as sexual dimorphism and ontogenetic polymorphism, are discussed. Some implications of the results obtained for the taxonomic treatment of Phalangiidae are also discussed. These results shed new light on the biology and evolutionary history of this fascinating group of arthropods.     

Sense organs in post-embryonic stages of Hyalomma marginatum marginatum Koch, 1844 (Acari: Ixodida: Ixodidae). II. Palpal organ.

Light microscopy and scanning electron microscopy (SEM) studies show the differences in structure, number and topography of terminal setae in the palpal organ in different stages of Hyalomma marginatum marginatum Koch, 1844. The palpal organ contains eight terminal setae in larvae and nymphs, and ten setae in adults. The length of these setae increases in the course of post-embryonic development. Other setae on palpal segments also undergo quantitative and morphological changes.     

Early leaf miners and the ground plan of the lepidopteran larval trunk: Caterpillar morphology of the basal moths Heterobathmia,Eriocrania, and Acanthopteroctetes

The larval trunk morphology including chaetotaxy, locomotory structures, and trunk musculature of Heterobathmia pseuderiocrania, Eriocrania cicatricella, and Acanthopteroctetes unifascia is described using conventional light, polarization, and scanning electron microscopy. The ground plan morphology of the lepidopteran larva and neolepidopteran caterpillar is discussed in light of the life history succession from free soil dwelling organism to endophagous and finally to a primarily free living, angiosperm associated organism. I suggest that the larval morphology is argued to be strongly influenced by the shift in number of surfaces present in the larval environment. Especially the environment of the endophagous species, where the upper surface of the leaf mine is linked to the presence of dorsal locomotory structures such as the retractable calli and dorsal friction patches is proposed to have had a significant impact on the morphology and locomotory mechnism of the lepidopteran caterpillar. The chaetotaxy of the lepidopteran ground plan is found to be simple, consisting only of primary and secondary tactile setae and segmental proprioceptors. The presumption of Gerasimov ([1935] Zool Anz 112:177–194) that MXD1 of the prothorax is a shifted mesothoracic MD setae is supported. I suggest that the serial arrangement of the proprioceptors MD1, present on all trunk segments except the prothorax, and a trisetous MV group on all the thoracic segments is part of the lepidopteran larval ground plan. The absence of apodeme structures associated with trunk musculature in the nonglossatans suggests that this is an autapomorphic character of the Lepidoptera and it is further found to have been influential in the evolution of the typical caterpillar trunk. The attachments of the thoracic muscles directly to the trunk integument, suggest that the apodemal structures ancestral to the Amphiesmenoptera have been reduced in the Lepidoptera. Within the non‐Neolepidoptera, the lifehistory shift may have resulted in reduction of the dorsal locomotory structures, such as calli. The abdominal musculature and structural similarities further suggest that the ventral calli are structural predecessors to the crotchet bearing proleg of the “typical caterpillar.” J. Morphol. 274:1239–1262, 2013. © 2013 Wiley Periodicals, Inc.     

Studies of male sexual tubes in hermit crabs (crustacea, decapoda, anomura, paguroidea). I. Morphology of the sexual tube in Micropagurus acantholepis (Stimpson, 1858), with comments on function and evolution

The external morphology and internal structure of the male sexual tube of the hermit crab Micropagurus acantholepis, a member of the family Paguridae from Australian waters, is described in detail using histological thick sectioning and scanning and transmission electron microscopy techniques. This is the first in-depth study of a sexual tube in the Paguroidea, a group where a remarkable number of genera (55.9% in the family Paguridae) with species having these intriguing sexual structures are known. In M. acantholepis a sexual tube is present on the left side, whereas only a gonopore is present on the right side. The tube is used for the delivery of spermatophores to the female and consists of a sheath of cuticular origin surrounding an internal, functional extension of the posterior vas deferens. Pedunculate spermatophores were observed within the lumen and partially extruding from the terminal opening of the tube in preserved specimens. The tube protrudes from the left coxa of the fifth pereopod as an elongate 3-mm-long, hollow, coiled structure with a terminal opening. Exteriorly the tube consists of a conspicuous thick chitinous cuticular ridge throughout its length, and a thin chitinous cuticle with sparse, regularly arranged simple setae. Interior to the cuticle, the tube contains loose connective tissue, secretory cells, oblique muscle, circular muscle, and epithelial cells. The latter cells line a central lumen that runs the length of the sexual tube. The morphology, cellular composition, and function of the tube are discussed.     

Agnetina den, a new species of perlid stonefly (Plecoptera: Perlidae) from Vietnam

A new species of perlid stonefly, Agnetina den, is described from Vietnam. Male adults of this species can be easily distinguished by their black body color pattern, submedian patches of sensilla basiconica on hemitergites 7–8, and clusters of long dense fine setae on the inner sides the abdominal tergites. Illustrations of habitat and diagnostic characters are presented.     

The setae of parasitic Liphyra brassolis butterfly larvae form a flexible armour for resisting attack by their ant hosts (Lycaenidae: Lepidoptera)

Caterpillars of the lycaenid butterfly, Liphyra brassolis, live inside the nests of arboreal weaver ants, Oecophylla smaragdina, and eat their brood. Observations of mature larvae suggest that they are impervious to relentless ant molestation, yet they lack sclerotized cuticular plates. We document a novel form of integumental defence that imparts protection from ant attack whilst maintaining the flexibility necessary to walk with a hydraulic skeleton. Analysis of the trunk integument and cuticular structures of early and late instars of L. brassolis using light microscopy, scanning electron microscopy, and histology revealed three new setae types (disc, clavate, and lanceolate), as well as three new cuticular structures (pored sockets, cuticular pores, and cuticular domes). The unique cuticle is covered with lanceolate setae, which act as endocuticular struts, and overlapping scale‐like sockets, which form a hard, flexible integument. The imperfect armour of the early‐instar larvae suggests that abundant, putatively secretory pores are likely to be homologous to pore cupola organs (PCOs) found in other lycaenid larvae and thus may exude semiochemicals to allay ant aggression. The importance of these pores presumably wanes as structural (setal) cuticular defenses are reinforced in later instars, when adult ants have been observed attacking caterpillars to no avail. The caterpillar's antennae are unusual and seem to be involved in manipulating ant larvae into the caterpillar's mouth. Behavioural observations indicate that the dexterity of these structures is associated with eating ants (myrmecophagy).     

Morphological diversity of setae on the grooming legs in Anomala (Decapoda: Reptantia) revealed by scanning electron microscopy

The fifth pereiopods (P5) in Anomala are specialized appendages used mainly for grooming. We studied the articulated cuticular outgrowths, setae, on the distal segments of the P5 in 40 species from 18 Anomala families using light and scanning electron microscopy. Five general classes of setae can be found on the P5: serrate, serrulate and simple setae which all appear bristle-like, and tooth-like and scale-like cuspidate setae. We classified the bristle-like setae according to criteria of shape and the arrangement of distinct outgrowths – denticles and setules – on the shaft of the seta. In this way we were able to distinguish eleven mainly serrate and serrulate types of seta. Some setal types imply homology due to their distinctness and could thus help to solve problematic phylogenetic questions. One setal type, for example, is only present in pagurid hermit crabs and king crabs, which corroborates the theory that these two morphologically very dissimilar groups are, in fact, closely related.     

Pheromonal emission during the mating behavior ofEurycotis floridana (Walker) (Dictyoptera: Blattidae)

The sexual behavior of males and females ofEurycotis floridana was investigated and the various associated behavioral sequences are described. Olfactometer data proved that the male produces a volatile sex pheromone attractive at a distance to conspecific females. The male initiates courtship behavior by exposing the glandular areas on the anterior parts of abdominal tergites 2, 7, and 8. This male calling behavior was observed throughout the day. The males can mate when 8 days old, whereas virgin females are sexually receptive 18 days after becoming adults. Once attracted near the male, the female opens her genital atrium and climbs on the back of the male, where she feeds on the glandular secretions that oozed around a little tuft of setae on the first tergite. These setae are mechanoreceptors and they are stimulated when licked by the females, which informs the male that she is in a proper position for copulation.     

Local sex-ratio dynamics: a model for the dioecious liverwort Marchantia inflexa

In many dioecious bryophyte species, population sex ratios range from all female to all male. The focal species of the present study, the liverwort Marchantia inflexa, forms patches on rock and bark surfaces, and these differ widely in sex ratio at a rainforest field site in Trinidad. This analysis – to our knowledge the first modeling study of sex-ratio dynamics in a dioecious clonal organism – addresses abundances of male and female M. inflexa through time within an individual patch. We represent the life history of this species using seven different stages (non-reproductive, asexually reproductive, sexually reproductive males, non-reproductive, asexually reproductive, unfertilized and fertilized sexual females) and express their dynamics using ordinary differential equations. Some of the stages become more abundant as thalli extend over the substrate and may overgrow each other to capture space. Our simple representation of dynamics within the patch failed to stabilize the sex ratio: females gradually eliminated males at low to moderate disturbance frequency and males eliminated females at high disturbance frequency. This pattern did not hinge on whether sexual propagules could germinate within the patch, but asexual reproduction (via gemmae dispersed within the patch) played an important role. This suggests that the maintenance of sex in these populations may hinge on metapopulation structure and dynamics. Though sexual reproduction appears to be unimportant within patches, spores provide the primary means of recolonizing patches eliminated by large-scale disturbances. We found that shortly after the patch was fully occupied, the production of these wind-dispersed spores was maximized, but spore production declined thereafter as the sex ratio became increasingly biased toward one sex or the other. Much additional modeling and empirical work is needed to link within-patch dynamics across patches and account for dynamics at the metapopulation level.     

Sexually dimorphic mechanosensitive swimmeret sensilla affect abdominal posture in the lobster

The sensilla on the male and female second swimmerets are sexually dimorphic. Female swimmerets contain many long "smooth hairs" (long simple setae) on the coxa and rami. The endopodite of the male swimmeret has an accessory lobe covered with short "bristly spines" (serrate setae). In both sexes the swimmeret rami are lined by "feathered hairs" (plumose setae). The influence of mechanosensory stimulation of these sensilla upon abdominal tonic motor activity was analyzed in an in vitro swimmeret-nerve cord preparation. Movement of several clusters of smooth hairs produced an abdominal extension program by exciting the flexor inhibitor f5, inhibiting the flexor excitors, and activating several extensors. Stimulation of the male bristly spines excited the medium-sized flexor excitors f3 and f4. In both sexes the feathered hairs did not generate any response to mechanical stimulation. We infer that in nongravid females the smooth hairs are involved in receiving mechanosensitive cues to support abdominal extension. Bristly spines may contribute to postural adjustments that assist mating. The long latencies of these responses and their propagation to adjacent ganglia suggest that they are mediated by postural interneurons rather than by direct afferent terminations on postural motoneurons.     

Chemoreception in four species of water mites (Acari: Hydrachnida): behavioural and morphological evidence

Silver nitrate staining of the solenidial and eupathidial sensilla on the palpi, tarsi and tibiae of legs I and II of Arrenurus acutus, Geayia ovata, Mideopsis reelfootensis and Albia caerulea, along with ultrastructural studies, showed that these setae have a porous shaft cuticle. These setae are hollow and contain dendrites in their lumens and more than one neuron is associated with each setae. Behavioural experiments supported the involvement of these sensilla in the perception of chemical cues from prey and sexual partners.