Evolution of Opsin Genes in Caddisflies (Insecta: Trichoptera).

Insects have evolved complex and diverse visual systems in which light-sensing protein molecules called "opsins" couple with a chromophore to form photopigments. Insect photopigments group into three major gene families based on wavelength sensitivity: long wavelength (LW), short wavelength (SW), and ultraviolet wavelength (UV). In this study, we identified 123 opsin sequences from whole-genome assemblies across 25 caddisfly species (Insecta: Trichoptera). We discovered the LW opsins have the most diversity across species and form two separate clades in the opsin gene tree. Conversely, we observed a loss of the SW opsin in half of the trichopteran species in this study, which might be associated with the fact that caddisflies are active during low-light conditions. Lastly, we found a single copy of the UV opsin in all the species in this study, with one exception: Athripsodes cinereus has two copies of the UV opsin and resides within a clade of caddisflies with colorful wing patterns.

Holotype sequencing of Silvataresholzenthali Rázuri-Gonzales, Ngera & Pauls, 2022 (Trichoptera, Pisuliidae).

While DNA barcodes are increasingly provided in descriptions of new species, the whole mitochondrial and nuclear genomes are still rarely included. This is unfortunate because whole genome sequencing of holotypes allows perpetual genetic characterization of the most representative specimen for a given species. Thus, de novo genomes are invaluable additional diagnostic characters in species descriptions, provided the structural integrity of the holotype specimens remains intact. Here, we used a minimally invasive method to extract DNA of the type specimen of the recently described caddisfly species Silvataresholzenthali Rázuri-Gonzales, Ngera & Pauls, 2022 (Trichoptera: Pisuliidae) from the Democratic Republic of the Congo. A low-cost next generation sequencing strategy was used to generate the complete mitochondrial and draft nuclear genome of the holotype. The data in its current form is an important extension to the morphological species description and valuable for phylogenomic studies.

Elevational biodiversity gradients in the Neotropics: Perspectives from freshwater caddisflies (Insecta: Trichoptera).

Aquatic insects in the order Trichoptera are extremely diverse in number of species and their trophic roles. However, their distribution and diversity patterns are poorly known in the Neotropics, including the species restricted to tropical mountain ecosystems. Recent studies in tropical mountains have shown high levels of endemism of aquatic insects and changes in the composition of communities over short distances. Still, the incidence of environmental filters that explain such patterns has not been addressed quantitatively. Given the relevance of understanding Trichoptera spatial diversity patterns to prioritize conservation areas for freshwaters, as well as to obtain baseline information to predict changes in aquatic communities facing global environmental changes, we assessed the species distribution and assemblages of caddisflies along an elevational gradient from 600 to 3,600 m a.s.l. on the equatorial Andes. In this area, we had long-term continuous climate data with hourly resolution. We collected adult caddisflies in seven localities along this gradient using light traps. We sampled each locality for two hours after sunset for three consecutive days. All specimens collected were identified to species or morphospecies. Our results showed an increase in species and genera numbers with decreasing altitude, albeit no significant. Minimum air temperature is the main environmental variable explaining Trichoptera community assemblages. ß-diversity (taxon turnover among sites), as opposed to species richness, increased with altitude and showed a bimodal distribution along the elevation gradient for both genera and species assemblages, which resulted in a significant shift in community composition of species and genera at 2,000 m a.s.l. Our null-models confirm the observed patterns of B-diversity are non-random and suggest a strong environmental filtering of tropical caddisflies community assemblies and turnover. Geographic distance coupled with changes in environmental conditions along the elevation gradient explained a high percentage of community variance, as documented for other taxa (e.g., vascular plants), suggesting the importance of securing habitat connectivity along the altitudinal gradient to protect aquatic insect diversity effectively.

A new species of Silvatares (Trichoptera, Pisuliidae) from the Democratic Republic of the Congo.

A new species of caddisfly in the family Pisuliidae from the Democratic Republic of the Congo is described and illustrated herein, Silvataresholzenthali sp. nov. Based on the presence of a pair of spines on the endotheca, this species belongs to the thrymmifer group. Additionally, Silvatareslaetae is recorded for the first time from the D.R. Congo.

De Novo Genome Assembly and Annotation of an Andean Caddisfly, Atopsyche davidsoni Sykora, 1991, a Model for Genome Research of High-Elevation Adaptations.

We sequence, assemble, and annotate the genome of Atopsyche davidsoni Sykora, 1991, the first whole-genome assembly for the caddisfly family Hydrobiosidae. This free-living and predatory caddisfly inhabits streams in the high-elevation Andes and is separated by more than 200 Myr of evolutionary history from the most closely related caddisfly species with genome assemblies available. We demonstrate the promise of PacBio HiFi reads by assembling the most contiguous caddisfly genome assembly to date with a contig N50 of 14 Mb, which is more than 6× more contiguous than the current most contiguous assembly for a caddisfly (Hydropsyche tenuis). We recover 98.8% of insect BUSCO genes indicating a high level of gene completeness. We also provide a genome annotation of 12,232 annotated proteins. This new genome assembly provides an important new resource for studying genomic adaptation of aquatic insects to harsh, high-altitude environments.

New Atanatolica species from Ecuador (Trichoptera, Leptoceridae).

Four new species of Atanatolica Mosely are described from Ecuador: A.andina sp. n., A.angulata sp. n., A.curvata sp. n., and A.decouxi sp. n. These species belong to the A.dominicana group and constitute new records of the genus from Chimborazo, Imbabura, and Napo Provinces. Additionally, A.andina sp. n. represents the highest elevation recorded for any species in the genus at 3900 m. Size class data are also presented suggesting continuous larval growth for the probable larva of A.decouxi sp. n., described and illustrated here. A new distribution record is provided for A.manabi from Carchi Province.

Two new species of the rare Neotropical caddisfly genus Amphoropsyche Holzenthal (Trichoptera, Leptoceridae).

Two new species in the rare, endemic Neotropical caddisfly genus Amphoropsyche Holzenthal, 1985 are described from Ecuador (A. carchisp. n.) and Peru (A. matsigenkasp. n.) bringing to 17 the number of species known in the genus. Almost all species are known from only a few individuals and from even fewer localities. The new species belong to a group of 10 other species that have tergum X in the male genitalia divided into a mesal process and a pair of lateral processes. Amphoropsyche carchi can be separated from those species by the rounded mesal concavity, the short mesobasal lobe, and the short 2nd article of the inferior appendage, while A. matsigenka can be diagnosed by the very slender and straight inferior appendage, which bears a pair of spine-like mesoventral projections. We also present a new record for Amphoropsyche tandayapa Holzenthal & Rázuri-Gonzales, 2011, from Ecuador, previously known only from the male holotype.

New species of the endemic Neotropical caddisfly genus Contulma from the Andes of Ecuador (Trichoptera: Anomalopsychidae).

The genus Contulma Flint (Trichoptera: Anomalopsychidae) is composed mostly of regionally endemic species occurring above 2,000 m, with a few more widespread species and some that are found at lower elevations. Adults of three new species of Contulma are described and illustrated from the Andes of Ecuador, Contulma lina, new species, Contulma quito, new species, and Contulma sangay, new species. These species are similar to previously described species from the region, including C. paluguillensis, C. nevada, and C. lancelolata. New provincial records are provided for C. bacula, C. cataracta, and C. echinata. Contulma duffi Oláh, 2016 is considered a junior, subjective synonym of C. penai, Holzenthal & Flint, 1995. Also, we provide an identification key to males of the 30 Contulma species now known.

Diversity and distribution of the Caddisflies (Insecta: Trichoptera) of Ecuador.

BACKGROUND: Aquatic insects and other freshwater animals are some of the most threatened forms of life on Earth. Caddisflies (Trichoptera) are highly biodiverse in the Neotropics and occupy a wide variety of freshwater habitats. In Andean countries, including Ecuador, knowledge of the aquatic biota is limited, and there is a great need for baseline data on the species found in these countries. Here we present the first list of Trichoptera known from Ecuador, a country that harbors two global biodiversity "hotspots." METHODS: We conducted a literature review of species previously reported from Ecuador and supplemented these data with material we collected during five recent field inventories from about 40 localities spanning both hotspots. Using species presence data for each Ecuadorian province, we calculated the CHAO 2 species estimator to obtain the minimum species richness for the country. RESULTS: We recorded 310 species, including 48 new records from our own field inventories for the country. CHAO 2 calculations showed that only 54% of the species have been found. Hydroptilidae and Hydropsychidae were the most species rich families. We report the family Xiphocentronidae for the first time from Ecuador as well as several new records of genera from different families. DISCUSSION: As in the neighboring Andean countries of Colombia and Peru, it is common to find undescribed species of caddisflies. There are vast areas of Ecuador and the northern Andes that are completely unexplored, and we expect that hundreds of new species are yet to be discovered.

New synonyms in the highly diverse caddisfly genus Smicridea (Trichoptera, Hydropsychidae).

In this paper, Smicridea (Rhyacophylax) repula Oláh & Johanson, 2012 is synonymized with Smicridea (Rhyacophylax) lobata (Ulmer, 1909), and the species Leptonema islamarga Botosaneanu, 2002 is transferred to Smicridea (Rhyacophylax) as a synonym of Smicridea lobata. Additionally, we present more detailed illustrations of the male genitalia of Smicridea (Rhyacophylax) lobata and Smicridea (Rhyacophylax) signata (Banks, 1903), and include notes on their distributions to aid in the identification of these two, often-confused species.