Le filet-piège de la larve de Plectrocnemia conspersa (Trichopteres,Polycentropodidae)

Summary The catching-net of P. conspersa larva was studies with particular reference to: structure, building, larval activity inside it and its function in prey catching.The microscopic and macroscopic structure of this catching-net is similar to that Neureclipsis larvae, with an open-ended tunnel and two funnel shaped openings, but its shape is less regular.The building of this net lasts about four to six hours. After a wandering period, the larva first builds the open-ended tunnel and the two openings.Most of the time, the larva lives inside the open-ended tunnel, but it can also crawl into the entrances. Its activity does seem to be related to a diel periodicity.During the catching process, the chief function of the net is detection, after which the prey is taken in the same way as in a spider's web.     

A New Species of Plectrocnemia from Sicily (Trichoptera,Polycentropodidae)

Plectrocnemia alicatai sp.n. from Sicily (Nebrodi Mountains) is described and figured from the adult male.     

The genus Plectrocnemia Stephens of Japan (Trichoptera; Polycentropodidae)

The Japanese species of the genus Plectrocnemia Stephens (Trichoptera; Polycentropodidae) are revised based on examination of male material. Five new species are described: P. divisa, P. suzukii, P. corna, P. scoparia, and P. odamiyamensis. P. levanidovae Vshivkova et al. is recorded from Japan for the first time and redescribed. P. wui (Ulmer), P. tochimotoi Schmid, P. tsukuiensis (Kobayashi), and P. okiensis Kobayashi are redescribed. Arctopsyche hirayamai Matsumura is transferred to Plectrocnemia and redescribed. P. asuana Kobayashi, P. kadowakii Kobayashi, and P. makiensis Kobayashi are transferred to the genus Nyctiophylax Brauer.     

Microsatellites for the net‐spinning caddisfly Plectrocnemia conspersa (Polycentropodidae)

Six polymorphic microsatellites were developed for the caddisfly Plectrocnemia conspersa from two enriched partial genomic libraries. These represent the first microsatellites published for the order Trichoptera. We show that, whilst it is possible to develop a highly enriched library, isolation of polymorphic microsatellites is difficult for this species, as has been found in some other of invertebrate groups. The genotypes of 160 individuals were determined using these new loci. Observed heterozygosities ranged from 0.013 to 0.788. Despite their problematic isolation, polymorphic microsatellite loci show greater levels of variation than previously studied allozyme markers.     

New species of Plectrocnemia and Nyctiophylax (Trichoptera, Polycentropodidae) from China

Four new species of genus Plectrocnemia and 4 new species of genus Nyctiophylax are described, namely: Plectrocnemia verticalissp. n.; Plectrocnemia acuminatasp. n.; Plectrocnemia cryptoparameresp. n.; Plectrocnemia qianshanensissp. n.; Nyctiophylax (Nyctiophylax) senticosussp. n.; Nyctiophylax (Paranyctiophylax) gracilissp. n.; Nyctiophylax (Paranyctiophylax) pungenssp. n.; and Nyctiophylax (Paranyctiophylax) auriculatussp. n.     

Ultrastructure du labium de la larve du Speophyes lucidulus delarouzeei (Coleoptera,Catopidae)

We successively examined the two main parts of the labium: the ligula and the palps. The organs located on the ligula have a simple innervation and may represent various types of mechanoreceptors. The palps are crowned by 13 different sensilla which have various receptions (mechanoreception, olfaction, gustation). Several described sensilla hold an unknown function.     

Modalités du déclenchement du comportement de capture chez la larve d‘Agrion (Calopteryx auct.) splendens Harris (Odonatoptères)

Das Fangverhalten der Larven von Agrion splendens wird hauptsächlich durch Schwingungen ausgelöst, die durch den Platzwechsel der Beute entstehen. Ein künstlicher mechanischer Stimulator ermöglichte es, nacheinander den Einfluß der Amplitude, der Dauer und der Frequenz der Reize und der Form der Schwingungen zu untersuchen. Die Latenzzeit des Fangschlages verkürzt sich mit zunehmender Frequenz und Amplitude und mit abnehmender Dauer der Reize. Gleichzeitig erhöht sich die Frequenz der Fangschläge, ohne daß der Köder vorher genau untersucht wird. Ein Köder, der mit einer abklingenden oscillatorischen Bewegung vibriert, ist wirksamer als einer mit halb sinusoidaler Bewegung. Künstliche Reizung mit der Ködermethode erlaubte, die sofortige oder verzögerte Wirkung der durch die Beute erzeugten Schwingungen auf das Auslösen des Fangschlages zu prüfen: Die Fangmaske wird während oder nach den Reizserien ausgeworfen. Beide Wirkungen scheinen abhängig von den unregelmäßig verlaufenden oder sinusoidalen Schwingungen, die der Köder erzeugt, und von den Veränderungen der Amplitude während der Reizung: Das Einstellen auf den Fang scheint durch eine wellenförmige Bewegung mit geringfügigen Amplitudenschwankungen erleichtert zu werden. Wenn eine Welle am Anfang oder während der Reizung besonders groß ist, dann führt dies zu einem sofortigen oder späteren Fangschlag.     

A revised key to larvae of the genus Plectrocnemia (Polycentropodidae: Trichoptera) in Britain, with notes on Plectrocnemia brevis McLachlan

SUMMARY. The key distinguishes the previously unknown larva of Plectrocnemia brevis McLachlan from larvae of the other two British Plectrocnemia species, P. conspersa (Curtis) and P. geniculata McLachlan. Notes are given on the larval habitat, life cycle and identification of the adult of P. brevis.     

Two New Species of the Genus Plectrocnemia Stephens (Trichoptera: Polycentropodidae) from the Russian Far East

Two new species of the genus Plectrocnemia Stephens, Plectrocnemia levanidovae, sp. n., from Sakhalin Island and the southern Kuril Islands, and Plectrocnemia martynovae, sp. n., from southern Primorye, are described and illustrated. The new species belong to the P. tortosa Group and are the sister species of P. tortosa Banks, from China, and P. appensata Mey, from Vietnam.     

Location of copper in larvae of Plectrocnemia conspersa (Curtis) (Trichoptera) exposed to elevated metal concentrations in a mine drainage stream

Using histological techniques together with transmission electron microscopy and X-ray microanalysis, copper-containing granules (which also contain significant amounts of sulphur) have been observed in the cells of the malpighian tubules and in the subcuticular region of larvae of Plectrocnemia conspersa. It is suggested that the granules in both these regions are primarily pigment granules, which provide a mechanism for taking potentially toxic concentrations of copper (and possibly other metals) out of circulation. This mechanism of metal tolerance may in part account for the reported occurrence of larvae of P. conspersa in waters with elevated concentrations of trace metals.     

Ultrastructure de l'équipement sensoriel de la mandibule chez la larve duSpeophyes lucidulus Delar. (Coléoptère cavernicole de la sous-famille desBathysciinae)

Summary The sensorial organization of the mandible of theSpeophyes lucidulus larva is studied by means of electron microscopy.This sensorial apparatus is remarkably homogeneous, i.e. it includes only mechanoreceptors: — tactile receptors such as trichoide sensillae in the external edge of the mandible, — proprioceptors such as campaniform sensillae and scolopidia which are the more numerous.The latter, end in the zone of the mandible which are widely concerned with strains and deformations during mandibular movements.Furthermore, these receptors present certain original morphological features which are described below.Résumé L'organisation sensorielle de la mandibule de la larve duSpeophyes lucidulus est étudiée au microscope électronique. L'équipement sensoriel est remarquablement homogène puisqu'il ne comprend que des mécanorécepteurs: — récepteurs tactiles, comme les sensilles trichoïdes du bord externe de la mandibule, — propriocepteurs, comme les sensilles campaniformes d'une part et les récepteurs scolopidiaux d'autre part, qui sont les plus abondants.Ceux-ci se terminent dans les zones de la mandibule qui sont le plus fortement soumises à des tensions et des déformations lors des mouvements mandibulaires. Ces récepteurs présentent en outre certaines caractéristiques morphologiques originales que nous décrivons.

     

Twenty-four new species of Polycentropus (Trichoptera, Polycentropodidae) from Brazil

Twenty-four new species of the caddisfly genus Polycentropus (Insecta: Trichoptera: Polycentropodidae) occurring in Brazil are diagnosed, described, and the male genitalia of each are illustrated. Eighteen of the new species are placed in the Polycentropus jorgenseni species complex of the Polycentropus gertschi group of New World Polycentropussensu lato. Furthermore, 6 new species within the Polycentropus gertschi group (Polycentropus ancistrussp. n., Polycentropus boraceiasp. n., Polycentropus cariocasp. n., Polycentropus froehlichisp. n., Polycentropus galharadasp. n., and Polycentropus graciosasp. n.) are placed in an informal diagnostic cluster of species with Polycentropus urubici Holzenthal and Almeida. Ten of the other Polycentropus gertschi group species form a second cluster of diagnostically similar species, the Polycentropus soniae cluster (Polycentropus caaetesp. n., Polycentropus carolaesp. n., Polycentropus cheliceratussp. n., Polycentropus fluminensissp. n., Polycentropus itatiaiasp. n., Polycentropus minerosp. n., Polycentropus santateresaesp. n., Polycentropus soniaesp. n., Polycentropus tripuisp. n., and Polycentropus virginiaesp. n.). Two of the remaining 8 new species are included in the Polycentropus jorgenseni species complex (Polycentropus cipoensissp. n. and Polycentropus verruculussp. n.), while the remaining 6 are unique and cannot be placed in one of the groups at this time (Polycentropus acinaciformissp. n., Polycentropus amphirhamphussp. n., Polycentropus cachoeirasp. n., Polycentropus inusitatussp. n., Polycentropus paprockiisp. n. and Polycentropus rosalysaesp. n.).