The immature stages of Phylloicus lituratus (Trichoptera: Calamoceratidae) with new records of Phylloicus and Banyallarga species in northwestern Argentina and southern Bolivia

Phylloicus lituratus Banks 1920 larva and pupa were associated. It is a new record for Argentina and represents the most austral record for the species. New records of other Calamoceratidae species are provided also from northwestern Argen-tina and southern Bolivia. Banyallarga (B.) argentinica Flint 1983 is recorded for the first time for Bolivia; B. (B.) loxana (Navás 1934) and B .(B.) yungensis Flint 1983 are both newly recorded from Salta province in northwestern Argentina. Illustrations of male genitalia of all species and of immature stages of P. lituratus are included. Presence of a Banyallarga larva in a leaf case suggests a need to change some larval keys used to identify the two endemic genera of Neotropical Calamoceratidae.Fil: Rueda Martin, Paola Alejandra. Universidad Nacional de Tucuman. Facultad de Cs.naturales E Instituto Miguel Lillo. Instituto de Biodiversidad Neotropical; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentin

Leaf litter input and electrical conductivity may change density of Phylloicus sp. (Trichoptera: Calamoceratidae) in a Brazilian savannah stream

Objetivo: invertebrados fragmentadores são geralmente escassos em riachos tropicais, com evidências consideráveis sugerindo que a disponibilidade de recursos alimentares possa determinar esse padrão em riachos de cabeceira. O objetivo desse estudo foi avaliar os efeitos de variações na disponibilidade de recursos alimentares durante um ano na densidade Phylloicus sp. (Trichoptera: Calamoceratidae), o qual está entre os principais invertebrados fragmentadores em riachos de cabeceira neotropicais. Métodos Medimos a importância relativa da matéria orgânica vegetal alóctone em termos de entrada vertical (EV) e estoque bêntico (EB) na densidade de Phylloicus sp., entre outubro de 2012 e setembro de 2013, em um riacho preservado de terceira ordem no Cerrado, Distrito Federal, Brasil. Resultados Folhas foi a fração mais abundante na EV e EB (~70%). A biomassa de folhas foi alta durante todo o ano (biomassa mensal de 24,2 g.m–2 ±23,1 SD na EV e 46,1 g.m–2 ±76,7 SD no EB), aumentando ao final da estação seca (agosto a outubro). Phylloicus sp. Teve baixa densidade durante o ano (2,4 ± 4,9 ind.m–2 média±DP) e seu pico foi associado à maior biomassa de folhas na EV e maior condutividade elétrica no riacho. O pico bem definido de Phylloicus sp. em outubro sugere uma interação entre o aumento densidade de Phylloicus sp. e a entrada de folhas no final da estação seca. A condutividade elétrica também foi maior em outubro, refletindo um aumento nas concentrações de nutrientes na água durante esse período. Conclusões A disponibilidade de detritos foliares pode ser um fator determinante para a densidade sazonal de Phylloicus sp., sugerindo um efeito bottom-up em riachos tropicais. Mudanças no suprimento de recursos alóctones em riachos podem afetar as populações de fragmentadores como Phylloicus sp. e influências antropogênicas na vegetação ripária podem afetar processos ecológicos de grande importância para riachos de cabeceira.Aim: shredders are generally not abundant in tropical streams, and there is considerable evidence suggesting that the food supply drives this pattern in headwaters. The aim of this study was to assess the effect of variation in the availability of food resources, over one year, on the density of Phylloicus sp. (Trichoptera: Calamoceratidae), which is one of the main shredders in Neotropical headwaters. Methods We measured the relative importance of organic matter in terms of vertical input (VI) and benthic standing stock (BS) on Phylloicus sp. density from October 2012 to September 2013 in a preserved third order stream in the Cerrado savannah biome, Federal District, Brazil. Results Leaves were abundant (monthly biomass of 24.2 g.m–2 ±23.1 SD in VI and 46.1 g.m–2 ±76.7 SD in BS), increasing at the end of dry season (August to October) and comprised the most abundant fraction in VI and BS (~ 70%). Phylloicus sp. had a low density throughout the year (2.4 ind.m–2 ±4.9 SD) and its peak (13.7 ind.m–2 ±17.1 SD in October) was associated with greater leaf biomass in VI and high electrical conductivity in the stream. The well-defined peak of Phylloicus sp. density in October suggests interplay between the increase in Phylloicus density and the leaf litter that enters the stream at the end of the dry season. Electrical conductivity was also higher in October, reflecting an increase in nutrient concentrations in the water during this period. Conclusions The availability of leaf litter may be a determinant factor for the seasonal variation in Phylloicus sp. density in tropical streams, suggesting a bottom-up effect. Changes in the supply of allochthonous resources to the stream can lead to modification in populations of shredders, such as Phylloicus sp., and anthropogenic influences on the riparian vegetation can affect ecological processes of great importance to streams

Life History and Phenology of \u3ci\u3ePhylloicus pulchrus\u3c/i\u3e (Trichoptera: Calamoceratidae) In a Tropical Rainforest Stream of Puerto Rico

Caddisflies are abundant, diverse, and important insects in freshwater ecosystems. However our knowledge on their life history is incomplete, in particular for the Neotropics. The objectives of this study were to describe the life history and phenology of Phylloicus pulchrus in the Luquillo Experimental Forest, Puerto Rico. Eggs and larvae were reared to determine the species lifespan and time in each instar. Larval instars were determined based on a head width vs. pronotal suture length correlation (N= 120). Larvae and benthic leaf litter were sampled monthly at a headwater stream for a year; all specimens were classified into instars based on their case size. Adult P. pulchrus were sampled monthly for a year with a light trap and at various times with a Malaise trap. Monthly environmental variables were related to species and sex abundance. There was a gradient of egg development where eggs (within compound masses) closest to the water were more developed. There were five larval instars and reared larvae showed longer development times and more variable body measurements in later instars. The best correlation for larval instar determination was case length-head width (Pearson= 0.90, P= 2.2e-16, N= 120). Phylloicus pulchrus has a multivoltine life cycle, with asynchronous larval development. Adult abundance was low. First to third instar larvae were influenced significantly by rainfall and rainfall seasonality had a negative significant effect on second instar larval abundance (ANOVA= 7.45, P= 0.02).Compound egg masses were probably oviposited by different females that gathered for oviposition. Phylloicus pulchrus follows the predominant developmental characteristic of Trichoptera of having five larval stages. Development times were longer than expected (longest times for a Phylloicus species) and may be an effect of laboratory rearing. The influence of rainfall (and seasonality) on different larval instars highlights the importance of this variable on early larval development. The cause of low adult abundance remains unclear, but may be related to low emergence rates and trap efficiency. Rev. Biol. Trop. 66(2): 814-825. Epub 2018 June 01

Water quality in the Mondego river basin : pollution and habitat heterogeneity

The "IMAR- Departamento de Zoologia, Universidade de Coimbra" and "Direcção Regional de Ambiente e Ordenamento do Território" started a partnership with the objective of establishing bases for the assessment of water quality in the Mondego river basin. Here we present the preliminary results of the study. We sampled 75 sites covering the Mondego river basin. At each site we took 18 physical and chemical measurements and sampled macroinvertebrates with a hand net. Site quality was assessed by the application of a biotic index (BMWP'), water chemistry and habitat heterogeneity. Fifty two percent of the sites had good biological water quality (based on BMWP' index). The strongly polluted sites were concentrated in the Lower Mondego region. Thirty three percent of sites had bad chemical water quality and 45% of the sites had low habitat complexity. Only 40% of the sites with low biological quality also had low chemical water quality. We concluded that (1) in general, the waters on the Mondego river basin do not suffer from strong water pollution and (2) low BMWP' values can be explained by low water quality or low habitat heterogeneity (natural or man-made).El "IMAR- Departamento de Zoologia, Universidade de Coimbra" y la "Direcção Regional de Ambiente e Ordenamento do Território" iniciaron una colaboración con el objetivo de establecer las bases para la evaluación de la calidad del agua en la cuenca hidrográfica del Río Mondego. En esta publicación presentamos los datos preliminares de ese estudio. Se muestrearon 75 localidades, repartidas por toda la cuenca del Mondego. En cada localidad se midieron 18 parámetros químicos y físicos y se muestreó la comunidad de macroinvertebrados acuáticos con una red de mano. La calidad ambiental fue calculada mediante la aplicación del índice biótico BMWP', por las características químicas del agua y por la heterogeneidad del hábitat. Un 51% de las localidades muestreadas tenían una buena calidad ambiental, de acuerdo con el índice BMWP'. Los sitios fuertemente contaminados estaban concentrados en la zona del Bajo Mondego. Un 33% de los locales tenían una calidad química mala, mientras que el 45% tenían una baja heterogeneidad del hábitat. Solamente un 40% de las localidades con baja calidad biológica también tenían baja calidad química. Concluimos que (1) en general, las aguas de la cuenca del río Mondego no sufre de contaminaciones fuertes, y (2) que los bajos valores de BMWP' pueden ser explicados por la baja calidad del agua o bien por una baja heterogeneidad del hábitat (por causas humanas o naturales)

Effects of experimental pool level reduction on Phylloicus pulchrus (Trichoptera: Calamoceratidae) feeding and conspecific behavior from a tropical rainforest stream

  Increases in drought occurrence and persistence around the world prompts to the understanding of their effects on natural populations and ecosystem functioning. The main result of drought on streams is the fragmentation of stream ecosystems into isolated pools as streamflow and water depth decrease. There are limited studies on caddisfly response to reduced water levels and their effect on ecosystem functioning. The goal of this study was to evaluate how reductions in water levels, similar to those associated with droughts, influence feeding and conspecific behavior of Phylloicus pulchrus. Laboratory experimental pool reductions, simulating the natural conditions of the species in the El Verde Field Station, Luquillo Experimental Forest, were carried out for two weeks. Four rectangular plastic aquaria were filled to one third with stream water that was maintained aerated. Ten circular plastic chambers (with screen windows) with Guarea guidonea senescent leaves were placed inside each aquarium. Two stream pool levels (normal and low) were simulated with two treatments (experimental and control). Experimental chambers (n=20) contained fourth instar larvae (n=80, 40=normal, 40=low) while control chambers (n=20) did not. The effect of pool level reduction on leaf mass loss, aggressive interactions between larvae (> 25 % of their cases removed), and larval mortality were assessed. Reductions in pool level increased leaf mass loss (ANOVA: F=5.17, p-value=0.03), larval aggressive interactions (Chi square: x2=6.24, n=80, p-value = 0.01), and larval mortality (Chi square: x2=4.51, n=80, p-value = 0.03).This study shows the early response of a tropical caddisfly to an abiotic cue of a drastic environmental change. This research contributes to our scarce knowledge on caddisfly larvae leaf litter processing behavior during early stages of water reductions, such as those caused by droughts.  Aumentos en la ocurrencia y persistencia de sequías alrededor del mundo estimulan el entendimiento de sus efectos en las poblaciones naturales y funcionamiento del ecosistema. El principal resultado de las sequías en los ríos es la fragmentación del ecosistema riverino en pozas aisladas a medida que el flujo y la profundidad del agua disminuyen. Hay estudios limitados sobre la respuesta de los tricópteros a reducciones en niveles de agua y su efecto en el funcionamiento del ecosistema. El objetivo de este estudio fue evaluar como reducciones en niveles del agua, similar a las asociadas con sequías, influencian la alimentación y comportamiento conspecífico de Phylloicus pulchrus. Reducciones de pozas en laboratorio simulando condiciones naturales fueron empleadas por dos semanas. Cuatro acuarios plásticos rectangulares fueron llenados a una tercera parte con agua aereada de la quebrada. Dentro de cada acuario se colocaron diez cámaras plásticas circulares (con aperturas de malla) con hojas senescentes de Guarea guidonea. Se simularon dos niveles de pozas (normal y bajo) con dos tratamientos (experimental y control).  Las cámaras experimentales (n=20) contenían larvas del cuarto estadío (n=80, 40=normal, 40=bajo) mientras que las del control (n=20) no. Se evaluó el efecto de la reducción de pozas en la pérdida de masa de las hojas, interacciones agresivas (>25 % de su envoltura removida) y mortalidad larval. La reducción en el nivel de las pozas aumentó la pérdida de masa de las hojas (ANOVA: F=5.17, p=0.03), interacciones agresivas (Chi cuadrado: x2=6.24, n=80, p= 0.01), y mortalidad larval (Chi square: x2=4.51, n=80, p= 0.03). Este estudio muestra la respuesta temprana de un tricóptero tropical a una señal abiótica de un cambio ambiental drástico. Esta investigación contribuye al escaso conocimiento sobre el comportamiento de procesamiento de hojarasca en larvas de tricópteros durante etapas tempranas de reducciones de flujo, como las causadas por sequías

Comparative morphological and functional analysis of wing coupling and related structures in caddisflies (Insecta: Trichoptera)

Several orders of morphologically four-winged insects have evolved mechanisms that enforce a union between the mesothoracic and metathoracic wings (forewings and hindwings) during the wing beat cycle. Such mechanisms result in a morphologically tetrapterous insect flying as if it were functionally dipterous, and these mechanisms have been described for several insect orders. The caddisfly suborders Annulipalpia and Integripalpia (Trichoptera) have each evolved wing coupling apparati. At least three systems have evolved within the suborder Annulipalpia (Polycentropodidae; Hydropsychidae: Hydropsychinae, Macronematinae), and within Integripalpia the evolution of wing coupling mechanisms is diverse to the point that it defies simple enumeration into discrete categories; conservatively seven different mechanisms have evolved. The comparative and inferred functional morphology of the putative wing coupling mechanisms is described for families in both Annulipalpia and Integripalpia. A novel form-functional complex putatively involved with at-rest forewing-forewing coupling is described for Hydropsychidae: Smicrideinae (Annulipalpia) and Philorheithridae (Integripalpia: Brevitentoria), and the form-functional consequences of this novel mechanism for forewing-hindwing coupling are elaborated. Experimental evidence regarding coupled versus uncoupled flight is given for both Annulipalpia and Integripalpia, including the discovery of wing coupling in Polycentropodidae (Annulipalpia) and Brachycentridae (Integripalpia: Plenitentoria). Based on experimental evidence and comparative morphological considerations it is argued that wing coupling is a far more complex phenomenon than presence- absence. It is likely that all Trichoptera have coupled wings on the downstroke, with the synchronous downstroke enforced either by a fully developed wing coupling apparatus or, when present, by the interaction of the forewing jugal lobe and the hindwing frenular-type setae. It is also suggested that for several families and sub-family clades, the morphology of the wing coupling apparatus is a synapomorphy and contributes characters for phylogenetic analyses

Nomenclatural and systematic changes in the Neotropical caddisflies (Insecta: Trichoptera)

Recent work on a catalog of the Neotropical caddisflies has resulted in the recognition of the need to make numerous lectotype designations, new names for homonyms, specific and generic synonymies, transfers of species between genera and genera between families, and placement of many long ignored names of Muller and others

The family characters and relationships of Trichoptera as illustrated by head structures

Thesis (M.S.

The genus Psilotreta Banks (Trichoptera: Odontoceridae) in Vietnam

Eight species of the genus Psilotreta Banks (Trichoptera: Odontoceridae) are currently known from Vietnam: P. albogera Mey 1997, P. androconiata Mey 1997, P. bidens Mey 1995, P. enikoae Oláh and Johanson 2010, P. frigidaria Mey 1996, P. jaroschi Malicky 1995, P. papaceki Malicky 1995, P. spitzeri Malicky 1995. A new species, Psilotreta kurenschikovorum, from Thua Thien-Hue Province is herein described. The new species differs from other species of the genus by peculiarities in wing venation, by the unusual shape of epicranial suture on the head, and by the bifid apical segment of the inferior appendage. Additional province and collection information for previously recorded species are included

The Brachycentridae (Trichoptera) of Wisconsin

Five species of Brachycentrus and three species of Micrasema were collected. Previous records for Brachycentrus lateralis in Wisconsin are incorrect and should be for B. incanus. but B. lateralis larvae were collected recently in Douglas County. Brachycentrus americanus. B. numerosus. B. occidentalis, Micrasema kluane. M. rusticum and M. wataga usually occurred statewide in unpolluted permanent streams, but were generally absent from southern and eastern agricultural counties where most streams are organically enriched. More than one species and genus frequently occurred in the same stream. with Micrasema larvae often being found in streams with less current than required by Brachycentrus larvae. Larval cases of each species were usually distinctive in the last two instars. but there were variations due to habitat and ins tar. Brachycentrus americanus had a semivoltine life cycle in the northern half of Wisconsin and was univoltine in the south. Brachycentrus numerosus and B. occidentalis were always univoltine, but all Micrasema species had semivoltine populations and may be semivoltine in all Wisconsin streams