Morphology of the fifth sternal glands of Neotropical social wasps (Hymenoptera,Vespidae, Polistinae)

Glands play a central role in the social behavior of insects, and comparative analysis of their structure may provide insights about their evolution and their role in insect social biology. Here, we describe the glands of the fifth metasomal sternite of ten polistine wasps with different social behaviors. The glands of foragers of these species were studied using semithin sections of Araldite‐embedded tissue, and scanning electron microscopy. The structure of the glands observed was mostly similar to what has previously been reported for independent‐founder and swarm‐founder species, respectively. Scale‐shaped modifications in the fifth sternite are reported for the first time for members of the genera Synoeca and Epipona. Two previously unreported glands in the fifth sternite are also described. A more restrictive definition of the name Richards' gland is proposed, applying to the class 3 cells associated with scale modifications of the fifth sternite, based on structural differences between the glands observed, homology requirements, and functional evidence. Previous phylogenetic reconstructions of this character suggest that it appeared early in the Vespidae and disappeared four times, with a single reappearance in the genus Vespula. The restricted definition of Richards' gland suggests that this structure is an exclusive trait of the Epiponini, with two reversals.     

Morpho-functional variety of the coxal glands in cheyletoid mites (Prostigmata). II. Cheyletidae

Trombidiform mites are characterized by the presence of several paired glands in the anterior body portion united by a common conducting duct (podocephalic canal). Apart from the acinous (salivary) glands the podocephalic system includes a pair of tubular coxal glands (CGs) responsible for osmoregulation. The aim of the present study was to figure out how functional changes of acinous glands reflect on the corresponding CG. For this purpose, the anatomy and fine structure of the CG were analyzed in two mite species, Bakericheyla chanayi and Ornithocheyletia sp. (Cheyletidae), which have a different composition of their single acinous gland.The results showed that in both species the CG lacks a filtering saccule. It is composed of the proximal and distal tubes and leads into a cuticle-lined excretory duct. Both tubes demonstrate a similar species-specific fine structure. They are characterized by an extensive system of apical membrane invaginations (internal canals) associated with numerous large mitochondria. Local areas of modified internal canals were regularly observed in both species. They contain structures resembling those constituting filtering slit diaphragms of other animals.In O. sp., CG cells in addition demonstrate features characteristic of protein-like secretion. Apparently this correlates with the loss of true salivary glands in this species, as its acinous gland was previously assumed as silk producing. Contrary to this, the CG of B. chanayi shows no kind of granulation, which coincides with the presence of a salivary portion in its complex acinous gland.The microtubule-rich intercalary cells at the base of the excretory duct were associated with special muscles presumably regulating the dilation of the duct lumen. These cells might represent a basic feature common to different types of podocephalic glands.     

A new species of the leaf-beetle genus <Emphasis Type="Italic">Cryptocephalus</Emphasis> Geoffroy (Coleoptera,Chrysomelidae: Cryptocephalinae) from Southeastern Kazakhstan

A new species of the genus Cryptocephalus is described from the Malaysary Mountains (Southeastern Kazakhstan). The new species belongs to the subgenus Asionus and is closest to the group of species with a deep impression on the male anal (V) sternite (C. halophilus, C. impressipygus and C. mniczechi). Cryptocephalus malaysaryensis sp. n. clearly differs in the structure of the aedeagus and abdominal sternite V of the male.     

Topographical and numerical study of the idiosomal integumentary structures of the larva of four Neotropical species of <Emphasis Type="Italic">Amblyomma</Emphasis> Koch, 1844 (Acari: Ixodidae)

Integumentary structures of the larvae of Amblyomma longirostre (Koch, 1844), A. parvum Aragão, 1908, A. rotundatum Koch, 1844 and from three populations of A. cajennense (Fabricius, 1787) were studied using light microscopy. A new nomenclature for the localisation of the integumentary structures is proposed. Three types of integumentary structures were identified in the larval idiosoma of the four Amblyomma species: lyrifissures, small glands and large wax glands. These structures were observed isolated or associated over the entire idiosoma, except in the scutum, which lacked lyrifisures and large wax glands. Large wax glands were the most stable within and between the tick species, followed by lyrifissures and small glands. Small glands, although relatively stable, showed the highest number of numerical variations within and between the tick species. Even though there were intra-population variations in the topographical and numerical pattern of some integumentary structures of A. cajennense larvae, there was a definitive pattern for most of the specimens, as showed by the similar modal and mean numbers of integumentary structures per tick side. The patterns of lyrifissures, small glands and large wax glands showed little differences when compared between the four Amblyomma species; however, a few differences were well evident. These differences were sufficient to differentiate larvae of the four species. Thus, we expect that the study of integumentary structures on the larvae of other Amblyomma species will be useful in future taxonomic keys for the identification of Amblyomma larvae from the Neotropical region.     

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

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

Comparative morphology of the epidermis of seven species of polyclad flatworms (Platyhelminthes: Rhabditophora)

The ultrastructure of the epidermis of seven species of polyclad flatworms (Phaenocelis medvedica, Phaenocelis peleca, Pleioplana atomata, Boninia divae, Pericelis orbicularis, Enchiridium periommatum, and Cycloporus variegatus) representing six families is described. In all seven species, the epidermis consists of a single layer of columnar cells that rests on a bipartite basement membrane. Epithelial cell surfaces are covered by numerous microvilli and cilia. Cilia contain microtubules arranged in the 9 + 2 pattern, and from their basal bodies two striated rootlets arise, a rostrally directed one running parallel to the apical cell membrane, and a vertical one at a right angle to the first rootlet. Numerous epithelosomes and mitochondria occupy the apical parts of the cells. The basal part of the cells is highly folded, forming a cell web that connects to the basement membrane. The basement membrane consists of a thin basal lamina and a thick, multilayered reticular lamina. The number of layers in the reticular lamina varies among the different species and appears to be correlated with body size. Numerous canals containing either pigment granules or nervous processes perforate the basement membrane. We have identified four different types of glands: rhabdite glands, rhabdoid glands, mucoid glands containing vacuoles filled with flocculent material, and mucoid glands resembling thread cells of hagfish slime glands. The latter have been found only in P. orbicularis. Pigment cells were found in all species examined with the exception of C. variegatus, which takes its coloration from its ascidian prey. Our results further support the unique taxonomic status of Boniniidae.     

Sperm structure of Trichoptera. IV. Rhyacophilidae and Glossosomatidae

The families Rhyacophilidae and Glossosomatidae (Trichoptera) are considered to be the most primitive ones within the order. We examined the spermatozoa of members of these families to see whether their ultrastructure is consistent with an ancestral position. Axonemal structures, after fixation with a tannic acid-containing fixative, have been shown to be particularly useful as taxonomical indicators. It was found that 4 members of Rhyacophilidae, representing 3 subgenera (Rhyacophila, Pararhyacophila, and Hyporhyacophila) all have motile spermatozoa, with a 9 + 9 + 2 axoneme in which inner (but no outer) dynein arms are present. The accessory tubules have a wall consisting of 17 protofilaments, decreasing to 16 near the distal end, whereas the examined member of Glossosomatidae, Catagapetus nigrans, has accessory tubules with 18 protofilaments and a 9 + 9 + 2 axoneme with inner dynein arms and with motility similar to the Rhyacophilidae. Sperm motility is consistent with the inclusion of these 2 families within the suborder Integripalpia, and the axonemal pattern 9 + 9 + 2 indicates that the families indeed occupy a primitive position within Trichoptera.     

A new species of tumbling flower beetles of the genus Mordellaria (Insecta: Coleoptera: Mordellidae) from the Baltic amber

The beetle Mordellaria friedrichi sp. nov. is described from the Baltic amber. The new species differs from extant species of the genus in the shape of the eyes and antennae and in the ratios of the length of the pygidium and length of the elytron, pronotum, and anal sternite.     

Cardiocondyla pirata sp. n. – a new Philippine ant with enigmatic pigmentation pattern (Hymenoptera,Formicidae)

A new species of the ant genus Cardiocondyla Emery, 1869 – Cardiocondyla pirata sp. n. – is described from the Philippines. The species belongs to an Indo-Malayan group of six species that is characterized by workers having a strongly bilobate postpetiolar sternite and a thickset mesosoma with strongly convex dorsal profile as well as wingless, ergatoid males with sickle-shaped mandibles. The female castes show a pigmentation pattern not known from any ant worldwide. If having any adaptive value, a possible function of this structure is supposed to be visual dissolution of body shape in order to irritate predators.     

A new genus and species of Coenosiini from Costa Rica (Diptera,Muscidae, Coenosiinae)

Palpilongus gen. n. is herein described for one species – Palpilongus bifurcus sp. n., from Costa Rica, based on male and females. The striking morphological characters of the species – palpus very long, about as long as prementum; upper calypter truncate and very short and setae of male sternite 5 bifurcated, confirm that this new species is also a new genus in the tribe Coenosiini. Male and female terminalia were dissected and illustrated.     

To the species composition of rhagionid flies of the group subaquilus of the genus Chrysopilus (Diptera, Rhagionidae) in the Russian Far East

A group of the species closely related to Chrysopilus subaquilus and distributed in the eastern regions of Russia is considered. Two new species are described. Ch. leleji is closely related to Ch. kurenzovi Kriv. et Sid. Its tergites II-V are blackish brown at their bases, not paler than the others; sternite VIII is broad and rectangular; tergite IX forms a distinct cone-shaped opening. Ch. paradoxus is similar to Ch. subaquilus Nag., but its clypeus is red, not brown. In addition, this species differs distinctly from all the known species of this genus in the presence of lateral tubercles on tergite IX. The main morphological characteristics of Ch. subaquilus Nag., Ch. lilianae Sob., and Ch. yezonis Nag. are analyzed.     

西藏地区有瓣蝇类记述(三)花蝇科七新种描述

本文报道采自西藏的有瓣蝇类7个新种,均属花蝇科。正模标本保存在中国科学院上海昆虫研究所。 银额泉种蝇Pegohylemyia argyrometopa,新种（图1—3） 雄:体长6毫米。复眼裸,额宽约为前单眼宽的2倍,间额黑,间额鬃1,下眶鬃7—8,侧额及侧颜黑色上具银白色粉被,侧颜宽为触角第三节宽的4/3倍,触角黑,第三节长为宽的2倍,芒具毳毛,最长毛与芒基宽相等,颊高为眼高的1/5,银白色粉被明显,上倾口缘鬃3行,下颚须黑,中喙具粉被,长为高的4倍,口上片与额齐,后头背区有小毛。     

Species-specific sex pheromones secreted from new sexual glands in two sympatric fungus-growing termites from northern Vietnam, <Emphasis Type="Italic">Macrotermes annandalei</Emphasis> and <Emphasis Type="Italic">M. barneyi</Emphasis>

Summary Reproductive isolation in termites is not well known. Our study carried out on two sympatric species from northern Vietnam, Macrotermes annandalei and M. barneyi, showed that dispersal flights and sex pheromones were two important factors in their reproductive isolation. These fungus-growing termites were isolated, partially due to the timing of their respective dispersal flights. M. annandalei flew the first day after rain, while the flights of M. barneyi occurred the second day after rain. However, the flights can also be simultaneous in the two species. Sex pheromones of M. annandalei and M. barneyi were shown to be species-specific. In both species, they were secreted by females from two glandular sources, from tergal glands located on tergite 6 to 10 in M. annandalei and tergite 5 to 10 in M. barneyi, and from posterior sternal glands located on sternite 6 and 7 in both species. These posterior sternal glands, found for the first time in the Termitidae, were sex-specific glands. Although not fully identified, sex pheromones of M. annandalei and M. barneyi were clearly different from the trail-following pheromone secreted by the sternal gland stricto sensu located on the sternite 5. These results show that in termites, the sexual behaviour, the glandular origin of sex pheromones and their role in reproductive isolation greatly vary depending on the species and deserve to be more extensively studied.Received 8 April 2003; revised 1 September 2003; accepted 10 September 2003.     

New exocrine glands in the legionary ants of the genus Leptanilla (Hymenoptera,Formicidae, Leptanillinae)

Summary This paper reports the results of the first detailed study of the morphology of exocrine glands in two species of the ant subfamily Leptanillinae. Workers of Leptanilla escheri and L. japonica possess a large, unpaired sternal gland in the VIIth abdominal sternite, and an hypertrophied poison gland which is surrounded by a massive muscle layer. The sternal gland is absent in the queen of L. japonica, and the poison gland is highly degenerated. The queen is, however, endowed with a series of large, paired, intersegmental tergal and sternal glands, which occur between the IVth through the VIIth segments. The queen also posseses large spiracular plate glands.     

Comparative morphology of abdominal glands in Paederinae (Coleoptera : Staphylinidae)

Glandular structures at the sternites of 31 species of Paederinae (Coleoptera : Staphylinidae) are described in detail for the first time. A median gland of unknown biological significance is situated at the front margin of the 4th sternite in Paederus and Paederidus (Paederus s.l.). A gland tissue at the posterior border of the antecosta opens into a reservoir situated between the antecosta and the intersegmental membrane. Each of the numerous glandular units obviously consist of 2 secretory cells that are drained by a tubule. They are thus related to dermal glands. Two types of pores, single pores and pore plates, are dispersed over the body, but are aggregated in the vicinity of the aperture of the reservoir. In Rugilus, 2 hitherto unknown glands of the same shape are located at the front margins of sternites 4 and 5. In contrast to the glands of Paederus s.l., there are big pores under the gland tissue and the opening area lies in a pit. One further species, Stilicosoma rufipes, was recently classified in the genus Rugilus, but does not have any glands, and therefore the genus Stilicosoma Casey, which was once named for S. rufipes, is re-established. Ochthephilum fracticorne does not have a reservoir, but otherwise combines features of both the glands of Paederus s. l. and those of Rugilus. This link points out the possible derivation of these glands from a common origin. All species of Lathrobiina have accumulations of tubules at the front margins of at least the 4th sternites, and thus represent a rather primitive stage in the development of the glands, while the lack of glandular peculiarities at the 4th sternites in Medonina is plesiomorphic. With respect to a special type of dermal tubules, the genera Medon, Pseudomedon, and Sunius are distinguished from Lithocharis, hence denoting a clear dividing line between the subtribes Medonina and Lithocharina. These features as well as the glands themselves, provide the basis for clarifying the largely unknown phylogeny of Paederinae.     

Schistosoma mansoni: penetration apparatus and epidermis of the miracidium

Free swimming miracidia of Schistosoma mansoni were studied with the electron microscope for the purpose of describing the penetration apparatus and the epidermis. The penetration apparatus was composed of 3 unicellular glands which contain membrane-bound vesicles containing macromolecular diglycols. Each gland contained a nucleus, rough endoplasmic reticulum, Golgi complexes, numerous mitochondria, and glycogen stores. Each gland cell opened to the exterior through the apical papilla.The surface of the miracidium, with the exception of the apical papilla, was covered with ciliated epidermal cells containing numerous mitochondria, membranous bodies, and glycogen. No nuclei were detected within these epidermal cells. Intercellular ridges connecting with subepidermal cytons interrupted the epidermal cells at numerous points. The ridges were joined to the epidermal cells by septate desmosomes. Beneath the epidermal cells were found circular and longitudinal muscle bundles.Sensory structures of various types were associated with the outer covering. These consisted of (1) numerous “knob-like” cytoplasmic projections associated with epidermal cells, (2) bulbous, lamelloid structures with external cytoplasmic projections, and (3) ciliated nerve endings with posterior epidermal tiers and ciliated nerve pits associated with apical papilla.     

Ultrastructural and histochemical observations on the epidermis, presumptive tegument and glands of the miracidium of Gigantocotyle explanatum (Trematoda:Paramphistomidae)

Dunn T. S., Hanna R. E. B. and Nizami W. A. 1987. Ultrastructural and histochemical observations on the epidermis, presumptive tegument and glands of the miracidium of Gigantocotyle explanatum (Trematoda: Paramphistomidae). International Journal for Parasitology17: 885–895. The miracidium is invested with 20 ciliated epidermal cells arranged in four tiers (6: 8: 4: 2 = 20). Non-ciliated ridges of cytoplasm, located between the epidermal cells, are continuous with an extensive multivesiculate syncytium which underlies the body musculature and comprises the main bulk of the miracidium. It is suggested that the syncytium represents the presumptive sporocyst tegument. Two distinct types of glands are present in the anterior region of the miracidium, viz. a large, syncytial apical gland and a single pair of small, unicellular lateral glands. The apical papilla is formed by the bounding membrane of the apical gland, which is elevated into a complex network of anastomosing lamellae. The lateral glands terminate in discrete rosetteshaped areas on the apical papilla. The possible function of glands in digenetic miracidia and the nature of their secretions are discussed.     

Fine structure of the vomeronasal organ in the grass lizard, Takydromus tachydromoides

The squamates are composed of many taxa, among which there is morphological variation in the vomeronasal organ (VNO). To elucidate the evolution of chemoreception in squamate reptiles, morphological data from the VNO from a variety of squamate species is required. In this study, the morphology of the VNO of the grass lizard Takydromus tachydromoides was examined using light and electron microscopy. The VNO consists of a pair of dome-shaped structures, which communicate with the oral cavity. There are no associated glandular structures. Microvilli are present on the apical surfaces of receptor cells in its sensory epithelium, as well as on supporting cells, and there are centrioles and ciliary precursor bodies on the dendrites. In addition to ciliated cells and basal cells in the non-sensory epithelium, there is a novel type of non-ciliated cell in T. tachydromoides. They have constricted apical cytoplasm and microvilli instead of cilia, and are sparsely distributed in the epithelium. Based on these results, the variation in the morphology of the VNO in scincomorpha, a representative squamate taxon, is discussed.     

Functional anatomy of vagina muscles in the blood-feeding insect,Rhodnius prolixus

The physiology of the muscles associated with the vagina in the blood-feeding insect, Rhodnius prolixus Stal, was investigated with the use of Methylene Blue staining to visualize the anatomy, and a micro force transducer to record spontaneous and neurally-evoked contractions. The vagina is associated with a dorsal muscle and a set of paired lateral muscles. The dorsal muscle extends from the base of the common oviduct to apodemes located laterally on sternite VIII, the first genital segment. The lateral muscles extend from a medially-located apodeme on the posterior edge of sternite VI around each side of the common oviduct to travel posteriorly along the side of the vagina before inserting laterally on apodemes on sternite VIII. The vagina muscles display spontaneous and neurally-evoked contractions that are prolonged but transient. The response to evoked contractions shows that the muscles are innervated by both excitatory and inhibitory motor axons. The degree of tension generated by evoked contractions is dependent on the frequency of stimulation with maximal tension being generated at 20–30 Hz. This tension, which often exceeds 400 mg, is transient and returns to a baseline within 1 to 2 min during continuous stimulation. These results, which are the first to describe this chamber in this well-studied insect, are discussed with respect to the act of egg laying.