A revision of the Afrotropical genus Dhatrichia (Trichoptera, Hydroptilidae)

Five previously described species of Dhatrichia Mosely, 1948 are recognized: D. inasa Mosely, 1948 from Yemen; D. bipunctata Statzner, 1977 from Zaire; D. lerabae (Gibon, Guenda & Coulibaly, 1994) comb. n. from Burkina Faso and Ghana; and D. cinyra Wells & Andersen, 1995 and D. divergenta Wells & Andersen, 1995 from Tanzania. A sixth species D. feredougoubae Gibon, 1987 from the Ivory Coast and Ghana is transferred to Microptila Ris, 1897 comb. n. In addition, nine new species are described and illustrated as males: D. ankasaensis sp. n., D. botiensis sp. n., D. hunukani sp. n., D. minuta sp. n., D. paraminuta sp. n. and D. wliensis sp. n. from Ghana, D. anderseni sp. n. from Tanzania, and D. madagascarensis sp. n. and D. giboni sp. n. from Madagascar. Females are associated, described and illustrated for all species, except D. inasa and D. giboni. The larvae and pupae of D. ankasaensis, D. hunukani, D. lerabae, D. minuta and D. wliensis are described and illustrated as the first known immatures of the genus. Keys to known larvae, pupae, males and females are provided. A phylogenetic analysis of the genus revealed four species groups. The most plesiomorphous taxa are West African, followed by East African and Malagasian taxa. A sister group relationship between the Eburneo–Ghanean and the Sudanian biogeographical regions is encountered twice. Among several possible sister taxa, the sister group turned out to be Kumanskiella Harris & Flint, 1992 and Microptila Ris, 1897 in part, combined. Implications for generic classification and biogeography are outlined. A morphometric principal component analysis revealed good separation of the sexes by the number and shape of antennal segments, and by eye size. Other measures are strongly dependent on overall size, and show best separation of females between species and species groups. A functional fit between male inferior appendages and secondary sexual characters in female sternite VIII is demonstrated for all species with associated females.     

Life cycle, horizontal microdistribution and current resistance of Allogamus auricollis Trichoptera: Limnephilidae in an Austrian mountain brook

SUMMARY. 1. The life history, horizontal distribution at the sediment surface and the effect of water flow on the microdistribution of Allogamus auricollis (Pictet, 1834), a case-bearing caddisfly, was investigated in a mountain brook near Lunz, Lower Austria.
2. The average head-width increment per moult was proportionately constant at c . 48%; therefore Dyar's rule was applicable.
3. Allogamus auricollis has a 1-year life cycle with first and second instars most abundant in October. It overwinters primarily as third and fourth instars; pupae were observed in August.
4. Horizontal distribution patterns were investigated by means of bimonthly samples taken along the stream profile. All instars were most abundant near the banks: 86.5% of the total catch 1987–88 were collected 0–1.5 m from the banks.
5. Current speeds were measured at the sites of 2191 larvae (including all instars) and eighty-six pupae. Larvae were most abundant at current speeds of 0–5 cm s⁻¹ (i.e. 86.6% of the total catch 1987–88).
6. Laboratory data on different stages of resistance to drift in A. auricollis (Waringer, 1989) were tested for their application to field conditions. 90% of the total catch 1987–88 preferred areas at the substrate surface where they could remain fully retracted within their cases, unattached, even when the large lateral case surface area was directed towards the water flow. This was also true at times of high discharge where the size of these areas was considerably reduced.     

Revised classification and evolution of leucotrichiine microcaddisflies (Trichoptera: Hydroptilidae) based on morphological and molecular data

Hydroptilidae constitute the most diverse caddisfly family, with over 2000 species known from every habitable continent. Leucotrichiinae are exclusively New World microcaddisflies, currently including over 200 species and 17 genera. Phylogenetic analyses of Leucotrichiinae relationships based on 114 morphological characters and 2451 molecular characters from DNA sequences were conducted. DNA sequences analysed were from one mitochondrial gene, cytochrome oxidase I (653 bp), and four nuclear genes, carbamoylphosphate synthase (802 bp), elongation factor 1α (352 bp), histone 3 (308 bp) and 28S rDNA (336 bp). The morphological matrix included 94 taxa (with representatives of all included genera) and the molecular matrix included 62 taxa. Individual and combined datasets were analysed under parsimony and Bayesian inference. In addition, a relaxed molecular clock divergence time estimate was conducted to determine the age of the subfamily and major lineages. All Bayesian inference analyses strongly suggest a monophyletic Leucotrichiinae, which initially diverged at approximately 124 Ma into two monophyletic groups of genera. These groups are herein elevated to tribal status, Alisotrichiini trib.n. and Leucotrichiini Flint sensu n. Several genera of Leucotrichiini were not recovered as monophyletic clades and some nomenclatural changes are proposed to reflect their phylogenetic history. These include the synonymy of Abtrichia with Peltopsyche; transfer of Betrichia hamulifera to Costatrichia; transfer of Betrichia alibrachia and Costatrichia falsa to Leucotrichia; and transfer of Costatrichia fluminensis to Acostatrichia. Additionally, Tupiniquintrichia gen.n. is described to include Peltopsyche maclachlani and Leucotrichia procera. According to our results, crown diversifications of both Alisotrichiini trib.n. (～80 Ma) and Leucotrichiini sensu n. (～103 Ma) occurred after complete separation of South America from Africa. Current distributions of most leucotrichiine genera are probably a result of migration from South America towards the north using the proto‐Caribbean archipelago (100 to 49 Ma). This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:FB6A3385-323D-41AF-B4BE-E19A393A493C .     

Structures on the antennal flagellum of a caddisfly,frenesia missa (Trichoptera,Limnephilidae)

Non-innervated macrotrichia and microtrichia, thick-walled chemoreceptors and three kinds of thin-walled chemoreceptors are present on the antennal flagellum of Frenesia missa. One of the thin-walled receptors, the plate organ, is of a type not previously recorded for any insect. About four times as many plate organs are present on the flagellum of the male as on that of the female. They occur also on the maxillary and labial palps.     

A new species of the genus Palaeagapetus Ulmer (Trichoptera, Hydroptilidae) from Japan

A new species of hydroptilid caddisfly, Palaeagapetus fukuiensis sp. nov., is described based on adult and immature stages from Japan. The habitat and food of this species are noted. This species is more closely similar to the Russian Far Eastern species of Palaeagapetus than to the Japanese species.     

Three new species of Orphninotrichia Mosely (Trichoptera: Hydroptilidae) from Barrington Tops, New South Wales, a distribution extended, and remarks on generic placement

Abstract Three new species are described in the endemic Australian microcaddisfly genus Orphninotrichia Mosely (Trichoptera: Hydroptilidae: Hydroptilinae), all collected in the Barrington Tops area of north-eastern New South Wales: Orphninotrichia bilobata sp. n., O. claviculata sp. n. and O. dundungra sp. n. From the same area, Orphninotrichia papillata Wells, described from central Victoria, is newly recorded and noted for the atypical presence of a large gland on the dorsum of the male head. Comments are made on the still unresolved affinities of the genus Orphninotrichia , and a key to males of all species is provided.     

The Larval Stage of Chilostigma sieboldi McLachlan (Trichoptera,Limnephilidae), with Notes on Taxonomy and Distribution

The larva of Chilostigma sieboldi McLachlan is described. This is the first positive association of adults and larvae in the genus Chilostigma, which involves only two species in the boreal region. We recorded and confirmed the Holarctic species C. sieboldi from Kushiro Mire in eastern Hokkaido by close examination of male and female genitalia. In Japan this species has been collected only from Kushiro Mire.     

Revision and synopsis of the caddisfly genus Dicosmoecus (Trichoptera: Limnephilidae; Dicosmoecinae)

Six species of Dicosmoecus are recognized: the palatus species group of Siberia and Japan [palatus (McL.), obscuripennis Banks, and jozankeanus Mats.)]; and the atripes species group of western montane North America [atripes (Hagen), gilvipes (Hagen), and pallicornis Banks]. D. obscuripennis is re‐established as a valid species distinct from palalus and recorded from the Yukon Territory and Alaska, and also Siberia. Keys are provided for identification of males, females, and larvae. Hypotheses of phylogeny and biogeography are proposed, stating that the palatus and atripes species groups evolved independently in Asia and North America respectively; and that obscuripennis of the palatus group extended its range to North America during the Pleistocene Beringian land connection between the two continents.

Data on food, life cycle, habitat, and distribution are given for the North American species. Most Dicosmoecus appear to be generalized predator‐shredders with robust, toothed mandibles; but fifth instar larvae of D. gilvipes feed mainly by scraping rocks for diatoms, a behaviour which is evidently responsible for eroding the slender blade and weakly formed teeth of the mandible, unique to this species, to a uniform scraping edge. D. gilvipes is further distinctive in usually having a 1‐year life cycle, whereas atripes and the other North American species usually have a life cycle of 2 years.     

Contribution of fungal biomass to the growth of the shredder, Pycnopsyche gentilis (Trichoptera: Limnephilidae)

1.  1. It has been accepted that aquatic hyphomycetes colonising submerged leaves increase the nutritional value of leaf detritus and suggested that fungal biomass plays a greater role in the growth of shredders than leaf tissue itself. However, it is not clear what proportion of the nutritional needs of shredders is met by fungal biomass.
2.  We fed Pycnopsyche gentilis larvae with tulip poplar ( Liriodendron tulipifera ) leaf discs colonised by the aquatic hyphomycete, Anguillospora filiformis , which had been radiolabelled to quantify the contribution of fungal carbon to the growth of the shredder at different larval developmental stages. Instantaneous growth rates of larvae on this diet were also estimated.
3.  When provided with fungal-colonised leaves (14–16% fungal biomass), the third and the fifth instar larvae of P. gentilis grew at the rates of 0.061 and 0.034 day⁻¹, respectively, but on a diet of sterile leaves, both larval instars lost weight. The incorporation rates of fungal carbon were 31.6 μg C mg⁻¹ AFDM day⁻¹, accounting for 100% of the daily growth rate of the third instar larvae and 8.6 μg C mg⁻¹ AFDM day⁻¹, accounting for 50% of the daily growth rate of the fifth instar larvae.
4.  These results suggest that leaf material colonised by A. filiformis is a high quality food resource for P. gentilis larvae, and that fungal biomass can contribute significantly to the growth of these larvae. Differences in feeding behaviour and digestive physiology may explain the significantly greater assimilation of fungal biomass by the earlier instar than the final instar. To satisfy their nutritional needs the fifth instar larvae would have to assimilate detrital mass that may have been modified by fungal exoenzymes.     

Origin of the transition from aquatic to terrestrial habits in Nothopsyche caddisflies (Trichoptera: Limnephilidae) based on molecular phylogeny

The larvae and pupae of most caddisflies (Trichoptera) are aquatic, whereas the adults are terrestrial. However, the trichopteran genus Nothopsyche includes species with terrestrial pre-pupal and pupal stages and with an entirely terrestrial life cycle. The phylogenetic relationships within this genus, inferred from sequences of mitochondrial 16S and nuclear 18S ribosomal RNA genes, suggest that Nothopsyche species were originally aquatic and that a single lineage acquired tolerance to terrestrial habitats at the pre-pupal and pupal stages. In this lineage, N. montivaga became completely terrestrial. In addition, the larval case materials changed from plant matter to sand at one point in the phylogeny of this genus.     

Isolation and characterization of microsatellite markers in the caddisfly Drusus discolor (Trichoptera: Limnephilidae)

We describe the development of and amplification conditions for microsatellite primers isolated from the caddisfly Drusus discolor. Eight polymorphic microsatellite loci were developed and screened for variability using 37 individuals from two populations from central Europe. The primers yielded an average of 8.6 alleles per loci. No linkage disequilibrium between loci was detected, while three loci showed deviations from Hardy–Weinberg equilibrium in one of the two tested populations.     

The Trichoptera of Panama VIII. The Hydroptilidae of Panama: current status,biodiversity comparisons,projections, and needs

ABSTRACT

Through 2014, 73 species of microcaddisflies (Trichoptera: Hydroptilidae) were recorded from Panama. From 2015 to the present, an additional 91 species have been discovered. The reasons for this increase include more intensive collecting, repeated sampling over time at the same locations, and use of multiple collecting techniques. For the countries from Mexico to Colombia, only Mexico, Panama, and Costa Rica have been significantly collected. Calculation of Jaccard Similarity values amongst these three countries indicates little similarity amongst their hydroptilid faunas (all less than 10%). The affinity of Panama with other neighbouring regions is greatest within Central America and with Mexico. Based on recent work (2015–2017), we project a minimum of 300 microcaddisfly species and 550 total caddisfly species will be recorded for Panama within the next 10 years. At present, the greatest need is for training of native Panamanians in caddisfly systematics and biogeography.     

The chromosomes of the caddis-fly,Glyphotaelius pellucidus (Retzius, 1783) (Trichoptera: Limnephilidae,limnephilinae)

The chromosome number in the caddis-fly,Glyphotaelius pellucidus (Retz.) is: 2n =60, =59; n =30, =29, 30. The sex determining mechanism is XX-XO, the female being the heterogametic sex. The sex element is heteropycnotic at oogonial prometaphase and at oocyte pachytene. There are no chiasmata at oocyte diakinesis, whereas one or two of these occur per bivalent in the male. The smallest bivalent has a delayed pairing at spermatocyte diakinesis.     

Pleistocene divergence of Dinaric Drusus endemics (Trichoptera, Limnephilidae) in multiple microrefugia within the Balkan Peninsula

The Balkan Peninsula is one of three major European refugial areas. It has high biodiversity and endemism, but data on the age and origin of its fauna, especially endemics, are limited. Mitochondrial sequence data (COI and 16S genes) were used to study the population structure and phylogeography of the caddisfly Drusus croaticus and the phylogeny and divergence of seven other Drusus species, mostly range-restricted endemics of the Dinaric region of the Balkan Peninsula. The divergence of D. croaticus populations in Croatia and allopatric Drusus species in Bosnia dated to the Pleistocene, showing the importance of this time period for the origin and diversification of Balkan endemic taxa. The divergence of more distantly related species dated to the Late Miocene/Early Pliocene. Population genetic and phylogeographic analysis of 115 individuals from 11 populations of D. croaticus revealed a high level of genetic differentiation and absence of gene flow between populations separated by more than 10 km. The existence of allopatrically fragmented lineages in D. croaticus and the endemic Bosnian species is most likely the result of long-term isolation in multiple microrefugia, probably due to the specific habitat requirements and life-history traits of Drusinae coupled with the topographic complexity and historical changes in geomorphology of the region. Overall, these findings shed light on the processes generating the high genetic complexity of this refugial region that parallels the 'refugia within refugia' pattern widely reported from the Iberian refugium.     

Effects of Pacific salmon spawning and carcass availability on the caddisfly Ecclisomyia conspersa (Trichoptera: Limnephilidae)

1. The effects of spawning coho (Oncorhynchus kisutch) and chum salmon (Oncorhynchus keta) on the limnephilid caddisfly Ecclisomyia conspersa were evaluated by experimentally excluding salmon from the upper 14‐m stretch of a spawning channel by a wire‐meshed fence. Density, and development and growth rates, of larvae upstream of the fence (without salmon) were compared with those downstream (with salmon). 2. Larval density in the stretch with salmon declined during spawning, but increased again after spawning subsided and the carcasses of dead fish became available. In the stretch with salmon, larval density on salmon carcasses was seven to 37 times greater than on the adjacent channel substratum. The rate of larval development in the stretch with salmon was greater than that in the stretch without salmon. Two months after carcasses became available, 98% of larvae sampled from the stretch with salmon were in the fifth instar, compared to only 23% from the stretch without salmon. Body weight of E. conspersa in the stretches with and without salmon increased by an average of 3.04 and 2.38 mg, respectively, over a 6‐month period. 3. ¹⁵N values of larvae from the stretch with salmon increased following the arrival of the fish, suggesting that the larvae were feeding on salmon‐derived material, such as eggs and carcasses, which contain a high proportion of the heavier stable isotope. In contrast, ¹⁵N values of larvae from the stretch without salmon remained relatively constant throughout the experiment. The availability of salmon carcasses as a high‐quality food source late in larval development may increase survival and fecundity of E. conspersa. 4. These substantial differences were consistent with the view that they were due to the experimental exclusion of salmon and salmon carcasses from the upstream stretch, though the study was un‐replicated and thus precludes ascribing causation more definitely.     

The Immature Stages of Ptilocolepus extensus McLachlan, 1884 (Trichoptera: Hydroptilidae: Ptilocolepinae) with Notes on Biology

The last instar larva and the pupa of Ptilocolepus extensus McLachlan, 1884, an endemic of the Iberian Peninsula, are described for the first time. The final instar larva of Pt. extensus bears close resemblance to those of Ptilocolepus granulatus (Pictet, 1834), but the abdomen has a well-developed dorsal sclerotized plate on segment VIII; this is a morphological feature which has not been observed in any other Ptilocolepinae. Final instar larvae make dorsoventrally flattened, elongate-oval cases of leaf pieces from several moss and liverwort species; such cases are characteristic of the Ptilocolepinae. Some additional data on biology and geographical distribution are given.     

The influence of some ecological factors on the metabolism—temperature curve of the larvae of Limnephilus rhombicus (Trichoptera, Limnephilidae)

SUMMARY. The oxygen uptake of Limnephilus rhombicus , a typical inhabitant of lentic waters, was measured in three different experimental situations: in still water with a plastic mesh as a substrate, in stirred water with a plastic mesh and in still water without any substrate. Water flow caused a small increase in oxygen uptake at all temperatures but principally above 15°C. The presence or absence of the plastic substrate had little influence on oxygen uptake; L. rhombicus can be active over the whole range of temperatures studied but its activity is always small. Its metabolism—temperature curve stands out in having a plateau between 5 and 10°C, with a steeper part between 10 and 20°C, the slope of which varies according to the conditions. Maximum oxygen uptake at high temperatures was relatively low (1235 ± 153 μl O₂g dry wt-1h-1 at 25°C).
The results are compared with those obtained previously for the larvae of Microptema testacea which inhabit flowing zones in brooks. L. rhombicus larvae appear both as cold-water animals and as animals from highly variable biotopes. They are in fact very ubiquitous and occupy all lentic biotopes from cold and mountainous districts to temperate lowlands.