The Genus Rhyacophila Pictet (Trichoptera: Rhyacophilidae) in Vietnam

Currently, 20 species of the genus Rhyacophila are known from Vietnam. Of these, 17 species are distributed among eight species groups, with three species unassigned. Examination of material collected by personnel of the Royal Ontario Museum in Toronto, Canada has revealed six new species and five new records of Rhyacophila from Vietnam, distributed among six species groups, four of which are new to Vietnam. Newly described species include: Rhyacophila smithi, Rh. curriei, Rh. laocai, Rh. meyi, Rh. olahi, and Rh. fernandi. Rhyacophila bidens Kimmins, Rh. inaequalis Denning and Schmid, Rh. lhabu Schmid, Rh. malayana Banks, and Rh. rhombica Martynov are recorded from Vietnam for the first time. The females of four species, Rh. bidens, Rh. immaculata Mey, Rh. malayana Banks, and Rh. tamdaona Oláh, are described for the first time. All 31 species of Rhyacophila now known from Vietnam are included in this work, organized by branch and species group.     

Two new species of the genus Rhyacophila Pictet (Trichoptera: Rhyacophilidae) from India

Two new species of the genus Rhyacophila Pictet from the Indian Himalayas, i.e. Rhyacophila himalayensis n. sp. from Badrinath (Uttarakhand) of the R. divaricata branch and Rhyacophila indica n. sp. from Gangtok (Sikkim) of the R. vulgaris branch are described and illustrated.     

The larva of Rhyacophila ferox Graf, 2006 (Trichoptera: Rhyacophilidae) from the Eastern Alps (Carinthia,Austria)

The hitherto unknown larva of Rhyacophila ferox Graf, 2006, is described and discussed in the context of contemporary Rhyacophilidae keys. In addition, zoogeographical and ecological notes are included.     

The larva of Rhyacophila loxias Schmid, 1970 (Trichoptera: Rhyacophilidae) with notes on its ecology

The larva of Rhyacophila loxias Schmid, 1970 is re-described. The diagnostic features of the species are listed and illustrated, and some information on the ecology and distribution of R. loxias is included.     

Receptor neuron responses to potential sex pheromone components in the caddisfly Rhyacophila nubila (Trichoptera: Rhyacophilidae)

Olfactory single sensillum responses of male and female caddisflies Rhyacophila nubila (Trichoptera: Rhyacophilidae) were examined with the tungsten penetration technique to investigate the presence of receptor neurons tuned to potential sex pheromone components. The compounds tested in the experiment were heptan-2-one, nonan-2-one, (R)-heptan-2-ol, and (R)-nonan-2-ol, which have all been found to be present in female abdominal glands, plus the two antipodes (S)-heptan-2-ol and (S)-nonan-2-ol. Four types of receptor neurons were found in equal proportions in males and females. One type responded primarily to heptan-2-one. A second type responded primarily to (R)-heptan-2-ol and a third type primarily to its enantiomer (S)-heptan-2-ol. The fourth type of receptor neuron responded to nonan-2-one, (R)-nonan-2-one, and (S)-nonan-2-ol, with a bias to nonan-2-one. The receptor neurons responding to the tested compounds made up a great majority of the contacted neurons in both males and females.     

Trichoptera fauna from Nakhon Si Thammarat Range (southern Thailand), with the description of a new species of Rhyacophila Pictet, 1834 (Trichoptera: Rhyacophilidae)

Seventy-five species of caddisflies were found near eight waterfalls in the Tai Rom Yen National Park and the Khao Luang National Park, within Nakhon Si Thammarat Range, in southern Thailand. Rhyacophila suratthaniensis sp. n. is described and figured, based on adult males. Rhyacophila suratthaniensis sp. n. is distinguished from other species of the genus by the shape of its paramere: their basal part is broader than the apical one and is separated from it by a step; apex of the paramere bears many strong spines, which are arranged like in a toothbrush. Occurrence of Trichoptera species in the observed and neighbouring areas is discussed.

http://zoobank.org/urn:lsid:zoobank.org:pub:336401B5-DAAA-4818-90EA-5DCB1944D1F0     

Microhabitat selection and life cycle patterns of two Rhyacophila species (Trichoptera: Rhyacophilidae) in southern Ontario streams

SUMMARY.

• 1 Two species of predatory caddisfly larvae—Rhyacophila fuscula (Walker) and R. melita Ross—have overlapping longitudinal distributions in southern Ontario streams.
• 2 The populations were studied at sites in areas of overlap (sympatry) and allopatry to determine what resources were partitioned, and if partitioning varied in the zones of overlap.
• 3 Life cycle and species size variation resulted in substantial physical differences between these univoltine species for most months of the year.
• 4 In May, when larvae of both species were not significantly different in size, a detailed microhabitat field study found no difference in microhabitat use between allopatric populations of R. fuscula and R. melita. Microhabitat selection by R. fuscula remained constant at sympatric sites but R. melita showed a significant change resulting in reduced microhabitat overlap with R. fuscula.

     

The larval head anatomy of Rhyacophila (Rhyacophilidae) with discussion on mouthpart homology and the groundplan of Trichoptera

The external and internal features of the larval head of Rhyacophila fasciata (Trichoptera: Rhyacophilidae) were described in detail. Anatomical examinations were carried out using a multimethod approach including histology, scanning electron microscopy, confocal laser‐scanning microscopy, microcomputed tomography, and computer‐based three‐dimensional reconstructions. Additionally, the information on the larval head of Limnephilus flavicornis (Limnephilidae) and Hydropsyche angustipennis (Hydropsychidae) available in the literature were reinvestigated. These anatomical data were used to address major questions of homology and terminology, that is, the ventral closure of the head capsule, the sclerites, and appendages of labium and maxilla and their muscles. These topics were discussed by summarizing the main hypotheses present in the literature and a critical inclusion of new findings. Consequently, the inner lobe of the maxilla very likely represents the galea. The distal maxillary sclerite (palpifer) is an anatomical composite formation at least including dististipes and lacinia. Based on these homology hypotheses several potential groundplan features of the larval head of Trichoptera were reconstructed. The head of Rhyacophila shows several presumably plesiomorphic features as for instance the prognath orientation of the mouthparts, the well‐developed hypocranial bridge, the triangular submentum and eyes composed of seven stemmata. Derived features of Rhyacophila are the reduced antennae, the anterior directing of three stemmata and the shift of the tentorio‐stipital muscle to the mentum. J. Morphol. 276:1505–1524, 2015. © 2015 Wiley Periodicals, Inc.     

Molecular phylogeny of Himalopsyche (Trichoptera,Rhyacophilidae)

Species of the genus Himalopsyche (Trichoptera, Rhyacophilidae) inhabit alpine to montane environments in Central and East Asia and North America. Diversity of the genus is concentrated primarily in the Himalayas and surrounding mountain ranges. Phylogenetic hypotheses have hitherto been proposed based on morphological data. Here, we present the first molecular phylogeny of Himalopsyche based on six gene fragments, using three methods of phylogenetic inference. Based on the phylogenetic analyses, we re‐evaluated species groups suggested by previous authors based on adult male morphology. We found that the previously defined groups are largely supported by molecular evidence as well as larval and adult morphology. However, we modify the species groups so that Himalopsyche phryganea and Himalopsyche lepcha constitute monotypic groups, and so that the tibetana group and anomala group sensu Schmid & Botosaneanu are merged to a single group, here defined as the tibetana group. Thus, we propose that Himalopsyche can be divided into five groups: kuldschensis group, lepcha group, navasi group, phryganea group, and tibetana group. We also provide a biogeographic synthesis of Himalopsyche distributions.     

Unusual behaviour and morphology of some Rhyacophila Pictet, 1834 caddisfly (Trichoptera: Rhyacophilidae) larvae reflect their ability to use the hyporheic zone

We found that larvae of four Rhyacophila Pictet, 1834 species preferred the hyporheic biotope in rapids and glides, which appears to be an unusual habitat among species in this genus. These species, i.e., Rhyacophila nigrocephala Iwata, 1927, R. nipponica Navas, 1933, R. shikotsuensis Iwata, 1927 and R. kawamurae Tsuda, 1940, belonging to the nigrocephala species group, of which six species occur in Japan. To study the movement behaviour of these species in the hyporheic biotope, we introduced their larvae into a small aquarium with a sandy bottom substrate. The larvae of these species burrowed into the sand bed and moved smoothly through interstices using their forelegs and their highly flexible and elastic abdomens. The larval morphology of these six species differs from that of the representatives of the other species group of Japanese Rhyacophila. They have more slender and flatter head capsules, more elongate abdominal segments, shorter thoracic legs and more slender anal prolegs. These features are adaptations that allow these species to effectively use the hyporheic biotope by enabling them to burrow through the interstices.     

Xanthochorema paniensis (Trichoptera,Hydrobiosidae) New Species from Upland New Caledonia

Xanthochorema is a genus of the Hydrobiosidae (Trichoptera) endemic to New Caledonia, with four described species. A fifth, Xanthochorema paniensis new species, is described herein, based on a mature male pupa from the We Caot River, Mont Panié, northeast New Caledonia.     

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.     

云南等翅石蛾科五新种记述（毛翅目）

记述中国云南毛翅目等翅石蛾科 4属 5新种 ;杨氏梳等翅石蛾 Kisaura yangaeSun & Gui,sp.n.,双突短室等翅石蛾 Dolophilodes didactylus Sun & Yang,sp.n.,喙突闭室等翅石蛾 Doloclanes rhynchophysa Sun & Gui,sp.n.,齿肢闭室等翅石蛾 Doloclanes dentata Gui & Yang,sp. n.及四瓣合脉等翅石蛾 Gunungiella te-trapetala Sun & Gui,sp. n.,其中合脉等翅石蛾属 Gunungiella为中国新记录属。新种模式标本保存于南京农业大学昆虫标本室。     

The genus Rhyacophila Pictet, 1834 (Insecta: Trichoptera) in Kosovo

The Balkan Peninsula is known for its high species diversity, but it is also one of the least known areas of Europe. Many previously inaccessible regions lack reliable faunistic records. There are especially few data available for the highly diverse aquatic insects of the region. To help fill the gap, we conducted an extensive survey to map the Trichoptera fauna of the Republic of Kosovo, an area where faunistic records are extremely scarce. Adult specimens were collected during 2009 and 2010, with light traps and entomologic nets. Of 84 Trichoptera species identified from the 21 investigated stations, 15 belong to the genus Rhyacophila. This makes the genus the most species-rich in Kosovo. Rhyacophila fasciata and R. tristis are widespread in many streams and rivers all over the country, while R. balcanica, R. trescavicensis, R. obtusa and R. bosnica have limited distribution. Ten Rhyacophila species presented in this paper are recorded for the first time on the area of Kosovo. We also provide new data for the disjunctive distribution of R. palmeni in south-eastern Europe, from Kosovo and Croatia.     

Instar sizes,life cycles,and food habits of five Rhyacophila (Trichoptera: Rhyacophilidae) species from the Appalachian Mountains of South Carolina,U.S.A.

The larval head widths at each instar, life cycles, and food habits of late instars were determined for five species of Rhyacophila from two Appalachian mountain streams in South Carolina, U.S.A. Rhyacophila acutiloba Morse & Ross was univoltine with two cohorts, one emerging in the spring and another presumably emerging in early autumn. Rhyacophila fuscula (Walker), R. nigrita Banks, and R. carolina Banks were apparently multicohort, univoltine species with extended flight periods. Rhyacophila minor Banks was univoltine with a spring emergence. All species were predaceous and consumed mainly Plecoptera nymphs and Trichoptera larvae.     

Two New Species of Chaetopterygini (Trichoptera,Limnephilidae) from North-Eastern Turkey

In the present study, two new species of the tribe Chaetopterygini (Trichoptera, Limnephilidae) from north-eastern Turkey are described and illustrated. Rizeiella camiliensis sp.n. is the second species of the northern Anatolian genus Rizeiella and Kelgena macahelensis sp.n. is the third species of the Caucasian genus Kelgena.     

Prey switching in Rhyacophila dorsalis (Trichoptera) alters with larval instar

1. Ontogenetic shifts in predator behaviour can affect the assessment of food‐web structure and the development of predator–prey models. Previous studies have shown that the diel activity pattern and functional response differed between larval instars of the carnivorous caddis, Rhyacophila dorsalis. The present study examines switching by larvae of R. dorsalis presented with different proportions of two prey types; either small (length 2–4 mm) and large (5–8 mm) Chironomus larvae for second, third, fourth and fifth instars of R. dorsalis; or Baetis rhodani (9–12 mm) and large Chironomus larvae for fourth and fifth instars. Experiments were performed in stream tanks with one Rhyacophila larva per tank and 200 prey arranged in nine different combinations of the two prey types (20 : 180, 40 : 160, 60 : 140, 80 : 120, 100 : 100, 120 : 80, 140 : 60, 160 : 40 and 180 : 20). Prey were replaced as they were eaten. A model predicted the functional response in the absence of switching and provided a null hypothesis against which any tendency to switch could be tested. 2. There was no prey switching in the second and third instars, with both instars always showing a preference for small over large Chironomus larvae. Prey switching occurred in the fourth and fifth instars. As the relative abundance of one prey type increased in relation to the alternative, the proportion eaten of the former prey changed from less to more than expected from its availability, the relationship being described by an S‐shaped curve. In the experiments with small and large Chironomus, the two instars switched to large larvae when their percentage of the total available prey exceeded 29% and 37% for fourth and fifth instars, respectively. In the experiments with Baetis and large Chironomus, both instars switched to Baetis larvae when their percentage of the total available prey exceeded 36%. 3. Non‐switching in second and third instars was related to their feeding strategies, both instars preferring smaller prey items. When the fourth and fifth instars foraged actively at night, they preferred larger over small Chironomus larvae, but when they behaved as ambush predators at dusk, they captured the more active Baetis larvae in preference to the more sedentary large Chironomus larvae and only switched to the latter when they were >64% of the available prey.     

梳等翅石蛾属二新种记述(毛翅目:等翅石蛾科)

记述了梳等翅石蛾属2新种,即膨肢梳等翅石蛾Kisaura inflate,sp.nov.和凹背梳等翅石蛾Kisaura alveiformis,sp.nov.。     

Differences in drifting of larval stages of Rhyacophila nubila (Trichoptera)

Larval drift of the trichopteran Rhyacophila nubila (Zett.) was studied in a West Norwegian river. The frequency distribution of different instars in the drift samples was significantly different compared with the benthic samples. The drift, measured as the number which passed a transect of the river, rised markedly in periods of high water discharge. Different instars can be arranged according to the extent in which they are drifting: 2>3>4>1>5. Instar 1 and 2 shared a neutral phototaxis. From the 2nd instar and on, the larvae became increasingly night-active with a culmination in the last instar which was highly night active, also confined by laboratory studies. It is suggested that changes in activity patterns is associated with a shift towards a more carnivorous way of life.     

Dietary variations of predaceous caddisfly larvae (Trichoptera: Rhyacophilidae,Polycentropodidae and Arctopsychidae) from British Columbian streams

The diets of larval Rhyacophilidae (Rhyacophila inculta), Polycentropodidae (Polycentropus variegatus) and Arctopsychidae (Parapsyche almota and P. elsis) from five streams in the University of British Columbia Research Forest, British Columbia (Canada), are recorded and related to feeding mode/constructional activities and prey representation in the habitat. Particular attention was paid to the extent of dietary overlap and the degree of intraspecific dietary variations between streams. An overall similarity of the diets of the study species was notable and all commonly consumed chironomid (Diptera) larvae, Simulium (Diptera) and Zapada (Plecoptera), although there was interspecific variation in the relative importance of these items. Polycentropus variegatus and Parapsyche spp. ate Baetis and Paraleptophlebia, the latter predators also consuming Hydrachnellae (Acarina). Other prey were generally of minor importance and consequently interspecific dietary overlaps were high. Differences in the range of prey consumed by predaceous Trichoptera were apparent. Free-foraging R. inculta which selectively consumed sedentary simuliid larvae had the narrowest niche breadth. Parapsyche spp. and Polycentropus variegatus foreguts generally contained an over-representation of chironomid larvae compared to their proportionate occurrence in the benthos, and these caddisflies exhibited high niche overlap. The relative importance of chironomids as food for Parapsyche spp. and Polycentropus variegatus is attributed to prey behaviour, i.e. drift, and poorly developed escape responses when they are caught on the predator's net.