Description of Eucyclops tziscao sp. n., E. angeli sp. n., and a new record of E. festivus Lindberg, 1955 (Cyclopoida,Cyclopidae, Eucyclopinae) in Chiapas,Mexico

Two new species of the freshwater cyclopoid genera Eucyclops are described, Eucyclops tziscao sp. n. and E. angeli sp. n. Both species belong to the serrulatus-group defined by morphological features such as: the presence of distal spinules or hair-like setae (groups N1 and N2) on frontal surface of antennal basis; the fourth leg coxa with a strong inner spine that bears dense setules on inner side, yet proximally naked (large gap) on outer side; and a 12-segmented antennule with smooth hyaline membrane on the three distalmost segments. Eucyclops tziscao sp. n. is morphologically similar to E. bondi and E. conrowae but differs from these species in having a unique combination of characters, including a caudal ramus 4.05±0.25 times as long as wide, lateral seta of Enp3P4 modified as a strong, sclerotized blunt seta, coxal spine of fourth leg with inner spinule-like setules distally, and sixth leg of males bearing a strong and long inner spine 2.3 times longer than median seta. Eucyclops angeli sp. n. can be distinguished by an unique combination of morphological features: the short caudal ramus; the long spine on the sixth antennular segment of A1; the presence of one additional group of spinules (N12’) on the caudal surface of A2; the presence of long setae in females, or short spinules in males on the lateral margin of fourth prosomite; the strong ornamentation of the intercoxal sclerite of P4, specially group I modified as long denticles; the distal modified setae of Exp3P3 and Exp3P4 in females and males; and the short lateral seta of P5. Finally, we report on a new record of E. festivus in México, and add data on morphology of the species.     

Sense organs in post-embryonic stages of Hyalomma marginatum marginatum Koch, 1844 (Acari: Ixodida: Ixodidae). I. Tarsal sensory system.

Light and scanning electron microscopic studies showed the differences in morphology and in size of Haller's organ in larvae, nymphs and adults (females and males) of Hyalomma marginatum marginatum Koch, 1844. The length of the anterior pit setae increases during post-embryonic development. The localization of these setae is the same in all stages. Six setae (one porose seta, two grooved setae, two fine setae, one conical seta) contain anterior pit of various developmental stages. In nymphs and adults more numerous pores appear on the wall surface of porose seta than in the larval stage. The structure of the capsule roof also differs in various developmental stages. Haller's organ of Hyalomma m. marginatum shows great degree of morphological development which is connected with the complicated life cycle and feeding behaviour of this tick species.     

Ovipositor internal microsculpture in the Braconidae (Insecta, Hymenoptera)

Variation in the microsculpture of the ovipositor egg canal, the morphology of the tip of the upper valve, the structure of the valvillus and the apex of the lower valve seals, as revealed by scanning electron microscopy is described for members of 52 genera representing 30 subfamilies of Braconidae. The possible phylogenetic implications of this variation are discussed. Characters supporting monophyly of the cyclostome clade, and of the non-cyclostome subfamilies Agathidinae, Pselaphaninae and Sigalphinae are reported. Functional and phylogenetic implications are discussed and possible convergent evolution of some features associated with endoparasitism are considered in the light of recent molecular systematics findings. © 1998 The Norwegian Academy of Science and Letters     

吴氏角叶蚤幼虫形态记述及其与同属另外三种的比较（蚤目：角叶蚤科）

描述了吴氏角叶蚤Ceratophyllus wui Wang et Liu 的幼虫形态,并与同属三种蚤幼虫作比较,标本采自湖北省西北部神农架海拔2 300 m 短嘴金丝燕四川亚种 Collocalia brevirostris innominata巢窝内。     

Setal Structure, Functions and Interrelationships in Spirorbidae (Polychaeta, Sedentaria)

Typical thoracic setae are composed of longitudinally arranged cylinders ending as teeth at the oblique distal surface. Most thoracic 'blades' are rounded in cross section and show bilateral asymmetry. Some have teeth in oblique rows ("cross striations") on the side adjoining the tube wall. Sickle setae found posteriorly on the thorax have distal portions like abdominal setae. These are flat, each composed mainly of a palisade of spatulate units. On one side cylindrical elements may also be present, in patterns which are characteristic of some taxa. Uncini are made of rows (sometimes single) of shorter cylindrical elements with hooked ends pointing anteriorly. Anterior thoracic hooks are usually blunt, but pointed in the genus Janua. The collar setae assist withdrawal into the tube, the abdominal setae help with emergence, whilst other thoracic setae act as distance pieces, pushing the body to anchor the thoracic uncini against the opposite wall. The other uncini are brought into use by the prehensile abdomen. The flaccid ends of the sickle setae are readily lost in some taxa and their development or loss may reflect unimportant variations in strength of the adjacent abdominal field. Fin and blade setae are not very different from simple setae and the natural grouping of the genera into subfamilies shows that changes from one form of collar seta to another have occurred independently several times.     

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.     

Ultrastructure of tarsal sensilla and other integument structures of two Pseudocellus species (Ricinulei, Arachnida)

Ricinuleids are one of the least investigated groups of Arachnida. In particular, knowledge of their ultrastructure is poor. Observations of the distal tarsomeres of ricinuleids show differences in their shape and equipment of surface structures. Legs I and II are used by the Ricinulei to explore their surroundings with tentative movements. The tarsomeres of these legs show similarities in shape and surface structures that distinguish them from those of legs III and IV. In this study, 11 different structures of the tarsomere surfaces of two cave-dwelling species, Pseudocellus pearsei and P. boneti from México, were investigated for the first time with scanning and transmission electron microscopy and discussed regarding their possible function: 1) a single treelike ramifying seta resembles a no pore single-walled (np-sw) sensillum; 2) setae occurring in a small number and possessing a bipartite shaft represent terminal pore single-walled (tp-sw) sensilla. The surface of the proximal half of the shaft shows small branches. The distal half has a smooth surface; 3) long setae with conspicuous longitudinal lamellae show characteristics of chemoreceptive wall pore single-walled (wp-sw) sensilla; 4) frequent small wp-sw sensilla with flat and irregular lamellae; 5) very short wp-sw sensilla occurring solitary or in groups; 6) a few short setae with smooth surface correspond to wp-sw sensilla; 7) a single short clubbed seta articulating in a flat pit is considered to be a np-sw sensillum; 8) common long setae with a pointed tip show characteristics of mechanoreceptive np-sw sensilla; 9) ventral setae with adhesive and mechanosensory function are accompanied by multicellular "class III" glands; 10) slit organs with mechanoreceptive function; and 11) dome-like tubercles with no indication of sensorial function. Several of these sensilla form a sensory field on the dorsofrontal surface which is particularly pronounced on the distal tarsomeres of legs I and II.     

Redescription and assignment of Alona globulosa Daday, 1898 to a new genus Notoalona and a description of Notoalona freyi sp. nov.

The species Daday (1898) describes as Alona globulosa has been critically studied, based on many populations from tropical and subtropical regions of the world, over its whole geographical range. A new species and a new subspecies are described. Based on the morphological characters of this species group, which are markedly different from those of the genera previously used for this species, namely Alona, Alonella, and Indialona, a new genus Notoalona is established. N. globulosa (Daday, 1898) is designated as the type species. Morphological differences of Notoalona, Alona, Alonella, and Indialona are discussed. The diagnostic characters of the genus Notoalona include 1) two bean-like thickenings as headpores on the headshield, 2) a row of submarginal setae along the posterior half of the ventral margin of carapace, 3) first trunk limb ODL with one seta and IDL with 3 setae and a small seta-like notch, 4) small branched seta dorsal to posterior lobe of trunk limb-I, 5) entire carapace of the ephippial female modified as an ephippium with a foamy mass surrounding the egg. N. globulosa has a wide distribution in Asia, Africa, and Australia. The Australian material has been designated as the subspecies australiensis. N. freyi sp. nov. is known only from Florida, USA. More detailed studies are necessary to evaluate the taxonomic status of other populations from America including material described as Alonella sculpta, which certainly belongs to the genus Notoalona.     

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.     

河野脂螨发育各阶段外部形态扫描电镜观察

[目的]了解河野脂螨Lardoglyphus konoi各发育阶段外部形态和超微结构特征.[方法]利用室内培养获得的不同发育阶段的河野脂螨个体样本,在扫描电镜下观察各发育阶段(卵、幼螨、若螨和成螨)的外部形态和超微结构.[结果]河野脂螨卵呈椭圆形;幼螨足3对,未见生殖器官生长痕迹,生殖毛和肛毛缺如;若螨足4对,生殖器官...     

The Chemoreceptive Lattice Organs in Cypris Larvae Develop from Naupliar Setae (Thecostraca: Cirripedia, Ascothoracida and Facetotecta)

Lattice organs are peculiar chemoreceptors found only in the Crustacea Thecostraca (Facetotecta, Ascothoracida, Cirripedia). In these taxa, five pairs occur in the head shield (carapace) of the terminal larval instar (y-cyprid, ascothoracid larva, cyprid), which is the settlement stage. Lattice organs represent an autapomorphy for the Thecostraca but their evolutionary origin and possible homologues in other Crustacea remain obscure. We have used scanning electron microscopy to describe the setation pattern of the head shield in late nauplii of one species of Ascothoracida, one species of Facetotecta and several species of the Cirripedia Thoracica, Acrothoracica, and Rhizocephala. The naupliar head shield always carries two pairs setae situated anteriorly near the midline. Each of these setae carry a single pore, and positional, structural and ontogenetic evidence show that these setae are homologous in all the examined species and that they represent precursors of the two anterior pairs of lattice organs of the succeeding larval stage, viz., the ascothoracid larva (Ascothoracida), y-cyprid (Facetotecta), and cyprid (Cirripedia). This leads us to infer that lattice organs are among the most highly modified sensilla in all Crustacea and they have in most cases lost all external resemblance to a seta. The nauplii of the Rhizocephala carry an additional three pairs of setae situated more posteriorly on the head shield and they could be precursors of the three posterior pairs of lattice organs. All other species examined lack these posterior setae, except the Facetotecta which have one posteriorly situated pair.     

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.     

Idiosomal setae in the family Phytoseiidae (Acari: Mesostigmata): variation,geographical distribution and taxonomic considerations

Phytoseiidae classification is based on idiosoma chaetotaxy and the assumed evolutionary process is seta suppression. This article aims to determine how depilation could have taken place depending on seta position, subfamily and region. For this, the occurrence of 21 variable setae on dorsal and ventral shields was determined for 1996 species in seven biogeographical regions. The occurrence of eight rare setae assumed to be past relics and 11 rarely absent setae (assumed to be undergoing a loss process) was analysed. The subfamily Phytoseiinae has ‘lost’ the highest number of primitive setae, the subfamily Amblyseiinae has ‘retained’ the highest number and Typhlodrominae has an intermediate position, except for the seta z6. The subfamily Phytoseiinae shows the highest number of setae undergoing a loss process, whereas the subfamily Typhlodrominae has lost these setae in 674 species and subfamily Amblyseiinae in 415 species, making this latter subfamily that with the most retained dorsal setae. According to spatial seta occurrence, it could be hypothesized that Amblyseiinae originated from South Gondwana, Typhlodrominae from the Euro‐America region (Laurasia zone) and Phytoseiinae from the Ethiopian area. The presently admitted classification of Phytoseiidae is discussed with regard to the occurrence of rarely present setae (assumed to have been lost in high frequency). © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112 , 606–624.     

Giselinidae fam. nov., a new monophyletic group of cyclopoid copepods (Copepoda, Crustacea) from the Atlantic deep sea

Four new species of Cyclopoida from deep-sea waters are described and placed in two new genera: Giselina gen. n. and Sensogiselina gen. n. The new genera and species belong to a new monophyletic group within the cyclopinid cyclopoids. A new name, Giselinidae, is proposed for this monophylum. The new family is characterised by the combination of the following characters: (1) tergite of leg 1 fused to cephalosome dorsally, but incompletely fused laterally, (2) absence of aesthetascs on ancestral antennulary segments XVI, XXI and XXV, (3) absence of antennary exopodal setae, (4) presence of only three spines on distal exopodal segment of leg 1, (5) absence of inner setae on first endopodal segments of legs 1–4, (6) outer terminal and distal inner elements of distal endopodal segment of leg 4 transformed into spines, (7) distal outer element of leg 5 exopod transformed into a spine, (8) leg 6 with only one seta, and (9) furcal setae I and III located on dorsal margin. Received in revised form: 16 June 2000 Electronic Publication     

Ultrastructure of the frontal sensory fields in the Lynceidae (Crustacea,Branchiopoda, Laevicaudata)

The clam shrimp family Lynceidae is unusual in possessing paired fields of short setae on either side of the rostral carina. We describe the position of these fields relative to the direction of water movement in live animals as well as the external and internal structure of these setae. The majority of morphological features support a presumed chemosensory role for these sensilla. These features include the lack of a setal socket and the relatively short length of each seta. The low number of enveloping cells (three or four) is uncharacteristic of chemosensory setae and is more typical of mechanoreceptors, as is the absence of any pores on the setae; these characteristics indicate that these fields may have both functions. © 1994 Wiley-Liss, Inc.     

Ultrastructure of the spines and neck gland of Abananote hylonome Doubleday, 1844 (Lepidoptera: Nymphalidae)

The external morphology of the cuticular spines, and the ultrastructure of the spines and neck gland in fifth instar Abananote hylonome larvae was studied. The larvae are spiny along the length of their bodies. Along the length of the spines are setae with a swelling towards the apical region. Internally, in the base of each seta there is a complex of secretory cells surrounding a large vacuole continuous with the seta. The neck gland is eversible, composed of a pair of oval internal sacks connected to the exterior via an extracellular canal produced by an invagination of the cuticle. The sack cells surround a reservoir containing an amorphous substance. In both the spines and neck gland the nuclei are large and irregularly shaped, typical of defensive glands of Lepidoptera. The border of the cells adjacent to the vacuoles (spines) and the reservoir (neck gland) is made up of numerous microvilli. We suggest that defensive compounds are produced in the gland cells and then later released via the vacuoles in the spines and the extracellular canal in the neck gland.     

CHANGES IN THE CARBOHYDRATE CONSTITUENTS OF ELONGATING LOPHOCOLEA HETEROPHYLLA SETAE (HEPATICAE)

Sporophyte setae of Lophocolea heterophylla (a leafy liverwort) elongate solely as a result of the expansion of individual seta cells. Though seta walls thin considerably during elongation, colorimetric analysis indicates that 25-fold increase in seta cell length is accompanied by a 2-fold increase in cell wall carbohydrates. Carbohydrate reserves of setae were characterized histochemically and by paper chromatography. Starch diminishes during elongtion; polyfructosans and sucrose are replaced by fructose and glucose. Increase in wall material appears to be at the expense of these carbohydrate reserves in seta cells, and may be due as well to a transport of wall precursors from the gametophyte.     

Rheoptilum: A New Genus of Two-Tailed Baetidae (Ephemeroptera) from Madagascar

Rheoptilum gen. n. is established for R. arni sp. n. and R. lokohensis sp. n. from Madagascar. Imaginal and larval stages are both described. Rheoptilum nymphs have two important adaptations: mouthparts are highly modified for scraping and the habitus is adapted for fast flowing waters. The genus possesses an extremely broad labrum with distal margin almost straight, incisors almost fused, right prostheca long and slender, caudal filament reduced to a single segment, legs long and slender, dorsally bordered with long and thin setae and the body dorsoventrally flattened. This combination of features distinguishes Rheoptilum from other Afro-Malagasy baetid genera. The phylogenetic position of this new genus is discussed.