Phylogenomics recovers multiple origins of portable case making in caddisflies (Insecta: Trichoptera), nature's underwater architects.

Caddisflies (Trichoptera) are among the most diverse groups of freshwater animals with more than 16 000 described species. They play a fundamental role in freshwater ecology and environmental engineering in streams, rivers and lakes. Because of this, they are frequently used as indicator organisms in biomonitoring programmes. Despite their importance, key questions concerning the evolutionary history of caddisflies, such as the timing and origin of larval case making, remain unanswered owing to the lack of a well-resolved phylogeny. Here, we estimated a phylogenetic tree using a combination of transcriptomes and targeted enrichment data for 207 species, representing 48 of 52 extant families and 174 genera. We calibrated and dated the tree with 33 carefully selected fossils. The first caddisflies originated approximately 295 million years ago in the Permian, and major suborders began to diversify in the Triassic. Furthermore, we show that portable case making evolved in three separate lineages, and shifts in diversification occurred in concert with key evolutionary innovations beyond case making.

The genus Palaeagapetus Ulmer (Trichoptera, Hydroptilidae, Ptilocolepinae) in North America.

The genus Palaeagapetus Ulmer (Trichoptera, Hydroptilidae, Ptilocolepinae) is revised in North America. Descriptions of the western species, P. nearcticus Banks 1938, are provided with the first descriptions of the female, pupa, larva, egg and case and with notes on food, habitat and annual life cycle. The male and female of the eastern species, P. celsus Ross 1936, are described or redescribed with some ecological notes. Distributions of the two species are summarized.

Calamoceras sp. nov. (Trichoptera: Calamoceratidae) from the Western Rif area, Morocco.

We describe a new species of the genus Calamoceras which currently has only two species: Calamoceras illiesi Malicky & Kumanski 1974 and Calamoceras marsupus Brauer 1865. We also discuss its ecology by analyzing some biophysical parameters. The larva and the adult of this new species, Calamoceras riffensis sp. nov. have been found by specialists from the Rif region in northwestern Morocco since 1998. All the specimens collected differ from the two known species by conspicuous morphological differences.

Five new species of the genus Cheumatopsyche (Trichoptera: Hydropsychidae) from the Phetchabun Mountains, Thailand.

Five new species of the genus Cheumatopsyche (Trichoptera: Hydropsychidae) from the Phetchabun Mountains, Thailand, are described and illustrated. The national parks and wildlife sanctuaries in the Phetchabun Mountains are recognized as areas with a high density of endemic species deserving protection. Four new species of Cheumatopsyche (C. recta, C. diversa, C. triangula, and C. tongto) have been found in Phu Khieo Wildlife Sanctuary, Phu Kradueng National Park and Thung Salaeng Luang National Park; a fifth new species (C. cava) has been found in Phu Kradueng National Park. Describing hydropsychid species is important not only to study diversity and distribution but also to facilitate eventual descriptions of larvae for use in freshwater biomonitoring programs to detect pollution.

Associating life stages and sexes of Nearctic Polycentropus Curtis, 1835 (Trichoptera: Polycentropodidae) using mitochondrial DNA barcoding.

Alpha taxonomy of caddisflies (order Trichoptera) is based primarily on male genital morphology. As such, associations of adult females and other life stages typically require conclusive association with the species' identifiable male. The aim of this study was to use molecular methods to associate females and larvae of Polycentropus species represented in the Nearctic. Analysis of mtCOI sequences using distance- and tree-based methods resulted in the association of larvae for 14 species of Polycentropus (P. alabamensis Hamilton, Harris & Lago, 1990, P. blicklei Ross & Yamamoto 1965, P. carlsoni Morse 1971, P. carolinensis Banks 1905, P. colei Ross 1941, P. confusus Hagen 1861, P. denningi Smith 1962, P. elarus Ross 1944, P. gertschi Denning 1950, Polycentropus halidus Milne 1936, P. maculatus Banks 1908, P. pentus Ross 1941, P. rickeri Yamamoto 1966, and P. variegatus Banks 1900) and females for 2 species (P. carolinensis and P. chelatus Ross & Yamamoto 1965). Searches for, and descriptions of, diagnostic morphological characters for these previously unidentifiable life forms are now possible. The identity of the larva of P. centralis Banks, 1914 is confirmed and some interesting phylogenetic relationships and a possible cryptic species and potential synonyms are implied in the results. Targets for future immature- and female-male associations are discussed along with a preliminary assessment of morphological differences among larvae.

Caddisflies (Trichoptera) of Mongolia: an updated checklist with faunistic and biogeographical notes.

To establish the biogeographic affinities of the caddisfly fauna of Mongolia, published records and results of our faunistic studies were analyzed. This study captured more than 47,000 adults collected from 386 locations beside lakes, ponds, streams/rivers, and springs in ten sub-basins of Mongolia using Malaise traps, aerial sweeping, and ultraviolet lights. In total, 201 species have been recorded, and approximately 269 species may occur in Mongolia according to our estimation. In a comparison of species richness for the family level, the Limnephilidae and Leptoceridae were the richest in species. The families Brachycentridae, Glossosomatidae, and Psychomyiidae had low species richness, but they included the most dominant species in terms of abundance and/or the percentage of occurrence in the samples from multiple sub-basins. Comparing the sub-basins, the Selenge had the highest Shannon diversity (H' = 3.3) and the Gobi sub-basin had the lowest (H' = 1.5). According to the Jaccard index of similarity, caddisfly species assemblages of Mongolia's ten sub-basins were divided into two main groups: One group includes the Selenge, Shishkhed, Bulgan, Tes, and Depression of Great Lakes sub-basins; the other group includes the Kherlen, Onon, Khalkh Gol, Valley of Lakes, and Gobi sub-basins. The majority of Mongolian species were composed of East Palearctic taxa, with a small percentage of West Palearctic and Nearctic representatives and an even smaller percentage from the Oriental region, suggesting that the Mongolian Gobi Desert is, and has been, a significant barrier to the distribution of caddisfly species between China and Mongolia.

Distribution of Ecnomus McLachlan, 1864 (Trichoptera, Ecnomidae) from the Lower Mekong River with a description of Ecnomusstungtrengensis new species.

Background: Trichoptera were surveyed from four different physiographic regions of the Lower Mekong River, including the Northern Highlands, the Khorat Plateau, the Tonle Sap Basin and the Mekong Delta in Myanmar, Laos, Thailand, Cambodia and Vietnam. New information: Twenty-three species of the genus Ecnomus, including a new species, were identified and mapped. Ecnomusmammus Malicky & Chantaramongkol, 1993 is a common species which is found from Tonle Sab Basin and Mekong Delta. Ecnomusalkmene Malicky & Chantaramongkol, 1997, E.volovicus Malicky & Chantaramongkol, 1993 and Ecnomusquordaio Malicky, 1993 are the common species in the area of the Northern Highlands and the Khorat Plateau. Ecnomusplotin Malicky & Laudee 2010 is found in the Mekong Delta. Ecnomustriangularis Sun, 1997 is a new species record for Southeast Asia. In addition, E.stungtrengensis sp. n. is described and illustrated. The male genitalia of E.stungtrengensis sp. n. are clearly different from those of other species in the genus Ecnomus by the shape of superior appendages which are slender and bent downwards distally in lateral view.

Larval Taxonomy and Distribution of Genus Hydropsyche (Trichoptera: Hydropsychidae) in Northwestern Algeria.

The main purpose of our paper is to document genus Hydropsyche (Trichoptera: Hydropsychidae) in northwestern Algeria and to provide the larval descriptions of the species set. Larvae, pupae, and imagines were collected from 14 sampling sites over a five-year period (2014-2019). Eight Hydropsyche species have been identified, with Hydropsyche siltalai being a new record for Algeria and North Africa, and Hydropsyche pellucidula a new record for Algeria. A comparison of our checklist with those of the Moroccan Rif and Europe is provided, as well as the geographical distribution of each species. This Algerian Hydropsyche species revision provides precise and reliable taxonomic characters for distinguishing larvae of the species, and a taxonomic key is proposed for their identification. In addition, information regarding their distribution is included.

Interesting new Chinese species of Leptoceridae and Odontoceridae (Insecta: Trichoptera) from several recent collecting efforts.

In contravention of Article 16.4.2 of the International Code of Zoological Nomenclature (International Trust for Zoological Nomenclature 1999), the repository for the holotypes of these species was not mentioned by Yang et al. (2020), such that the names proposed for these species are presently nomina nuda.

Interesting new Chinese species of Leptoceridae and Odontoceridae (Insecta: Trichoptera) from several recent collecting efforts.

Nine new species of caddisflies are described from southeastern and central China, including 7 species of Leptoceridae: Ceraclea (Ceraclea) megalophyllon Yang Morse sp. n., C. (Athripsodina) aerumnula Yang Morse sp. n., C. (Ath.) lamellata Yang Hu sp. n., Oecetis (Oecetis) discedens Yang Morse sp. n., Oe. (Pleurograpta) spinellosa Yang Hu sp. n., Setodes charax Yang Morse sp. n., and S. scutatus Yang Morse sp. n. Two species of Odontoceridae also are included: Phraepsyche acuminata Yang Morse sp. n. and Psilotreta longicornis Yang Morse sp. n. The male genitalia of all species and female genitalia of C. megalophylla, C. lamellata, Oecetis discedens, and Oe. spinellosa are figured.

Four new species of Rhyacophila Pictet, 1834 (Trichoptera: Rhyacophilidae) from Southeast Asia.

Four new species of genus Rhyacophila are described and illustrated from Thailand and Myanmar, Southeast Asia. Rhyacophila longicaudata sp. n. is in the R. nigrocephala Group; the very long basal segment of each inferior appendage distinguishes it from other related species. Rhyacophila aksornkoaei sp. n. and R. limsakuli sp. n. are in the R. anatina Group: they can be differentiated from other species of the group by the brush-like parameres and presence of a ventral process of the aedeagus in R. aksornkoaei sp. n., and by the rectangular apical segment of each inferior appendage and the hooked parameres in R. limsakuli sp. n.. Rhyacophila kengtungensis is in the R. yishepa Group and is characterized by the subtriangular shape of the preanal appendages in dorsal view and by the very large dorsal appendages of the phallic apparatus.

Diversity and Ecosystem Services of Trichoptera.

The holometabolous insect order Trichoptera (caddisflies) includes more known species than all of the other primarily aquatic orders of insects combined. They are distributed unevenly; with the greatest number and density occurring in the Oriental Biogeographic Region and the smallest in the East Palearctic. Ecosystem services provided by Trichoptera are also very diverse and include their essential roles in food webs, in biological monitoring of water quality, as food for fish and other predators (many of which are of human concern), and as engineers that stabilize gravel bed sediment. They are especially important in capturing and using a wide variety of nutrients in many forms, transforming them for use by other organisms in freshwaters and surrounding riparian areas. The general pattern of evolution for trichopteran families is becoming clearer as more genes from more taxa are sequenced and as morphological characters are becoming understood in greater detail. This increasingly credible phylogeny provides a foundation for interpreting and hypothesizing the functional traits of this diverse order of freshwater organisms and for understanding the richness of the ecological services corresponding with those traits. Our research also is gaining insight into the timing of evolutionary diversification in the order. Correlations for the use of angiosperm plant material as food and case construction material by the earliest ancestors of infraorder Plenitentoria-by at least 175 Ma-may provide insight into the timing of the origin of angiosperms.

Trichoptera of Canada.

Trichoptera, or caddisflies, are common members of freshwater ecosystems as larvae and are important indicators of aquatic system health. As such, the species are relatively well studied, with keys available for larvae and adults of many of the taxa occurring in Canada. The number of species recorded from Canada since 1979 (Wiggins 1979) has increased from 546 to 636, an increase of 16.4%. Of those species newly recorded, 17 represent newly described taxa since 1979. Taking into consideration the species likely to be subsequently found in Canada based on records in adjacent parts of the United States and results from DNA barcoding, an estimated 129-181 species remain to be documented in Canada.

A review of the genus Metalype Klapálek, with descriptions of three new species from China (Trichoptera, Psychomyiidae).

Three new species of Metalype from China, Metalype hubeiensis Qiu & Morse, sp. n., Metalype shexianensis Qiu & Morse, sp. n., and Metalype truncata Qiu & Morse, sp. n., are described and illustrated. Metalype uncatissima (Botosaneanu, 1970) is reported from China for the first time. The differences between genus Metalype and genus Psychomyia are discussed and four Psychomyia species are transferred to Metalype: Metalype holzenthali (Schmid, 1997); Metalype klapaleki (Malicky, 1995a); Metalype kumari (Schmid, 1997); and Metalype nithaiah (Malicky, 2014). A key to the males of Metalype species of the world is provided.

New species of microcaddisflies from China (Trichoptera: Hydroptilidae).

Five new species of hydroptilids in four genera are described from China, including three new species in Hydroptilinae: Agraylea dactylina n. sp., Allotrichia rhynchophyllum n. sp., and Microptila hamatilis n. sp.; and two new species in Stactobiinae: Stactobiella mutica n. sp. and Stactobiella parallelica n. sp. New records are given for Stactobiella biramosa Martynov 1929 and Pseudoxyethira thingana (Oláh) 1989. Genera Agraylea, Allotrichia, Stactobiella, and Microptila are new to Chinese fauna.

Three new species of the genus Lepidostoma Rambur (Lepidostomatidae: Trichoptera) from India.

Three new species of the genus Lepidostoma Rambur are described and illustrated from the Indian Himalaya: Lepidostoma trilobatum sp. nov., L. lidderwatense sp. nov., and L. sainii sp. nov., all belonging to the Lepidostoma ferox Branch. With these new additions, the genus Lepidostoma is now represented by 50 species in India and over 450 species globally.

The Trichoptera barcode initiative: a strategy for generating a species-level Tree of Life.

DNA barcoding was intended as a means to provide species-level identifications through associating DNA sequences from unknown specimens to those from curated reference specimens. Although barcodes were not designed for phylogenetics, they can be beneficial to the completion of the Tree of Life. The barcode database for Trichoptera is relatively comprehensive, with data from every family, approximately two-thirds of the genera, and one-third of the described species. Most Trichoptera, as with most of life's species, have never been subjected to any formal phylogenetic analysis. Here, we present a phylogeny with over 16 000 unique haplotypes as a working hypothesis that can be updated as our estimates improve. We suggest a strategy of implementing constrained tree searches, which allow larger datasets to dictate the backbone phylogeny, while the barcode data fill out the tips of the tree. We also discuss how this phylogeny could be used to focus taxonomic attention on ambiguous species boundaries and hidden biodiversity. We suggest that systematists continue to differentiate between 'Barcode Index Numbers' (BINs) and 'species' that have been formally described. Each has utility, but they are not synonyms. We highlight examples of integrative taxonomy, using both barcodes and morphology for species description.This article is part of the themed issue 'From DNA barcodes to biomes'.

The genus Nyctiophylax Brauer in China (Trichoptera, Polycentropodidae).

Currently, 8 species of the genus Nyctiophylax Brauer are known from China. Examination of material collected from Guangdong, Guangxi, Jiangxi and Sichuan Provinces during 2004-2005 has revealed 4 new species and 2 new records of this genus, bringing the number of Chinese Nyctiophylax species to 14. Newly described species include: Nyctiophylax (Paranyctiophylax) crinalis n. sp., N. (P.) dactylatus n. sp., N. (P.) orbicularis n. sp., and N. (P.) macrorrhinus n. sp. Nyctiophylax (Paranyctiophylax) sagax Mey and N. (N.) amphonion Malicky & Chantaramongkol are newly recorded for the Chinese fauna, which are re-illustrated and re-described for clear comparisons. The additional collection sites for the previously described species are provided. 

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.

Assessing macroinvertebrate biodiversity in freshwater ecosystems: advances and challenges in DNA-based approaches.

Assessing the biodiversity of macroinvertebrate fauna in freshwater ecosystems is an essential component of both basic ecological inquiry and applied ecological assessments. Aspects of taxonomic diversity and composition in freshwater communities are widely used to quantify water quality and measure the efficacy of remediation and restoration efforts. The accuracy and precision of biodiversity assessments based on standard morphological identifications are often limited by taxonomic resolution and sample size. Morphologically based identifications are laborious and costly, significantly constraining the sample sizes that can be processed. We suggest that the development of an assay platform based on DNA signatures will increase the precision and ease of quantifying biodiversity in freshwater ecosystems. Advances in this area will be particularly relevant for benthic and planktonic invertebrates, which are often monitored by regulatory agencies. Adopting a genetic assessment platform will alleviate some of the current limitations to biodiversity assessment strategies. We discuss the benefits and challenges associated with DNA-based assessments and the methods that are currently available. As recent advances in microarray and next-generation sequencing technologies will facilitate a transition to DNA-based assessment approaches, future research efforts should focus on methods for data collection, assay platform development, establishing linkages between DNA signatures and well-resolved taxonomies, and bioinformatics.