Trichoptera: Limnephilidae of Gunnison County, ColoradoAsynarchus nigriculus(Banks, 1908)Updated 21 February 2026
TSN 116238  Egg masses in a wet spot under a log at the edge of a pond. This species is sometimes hard to separate from various Limnephilus species found in the same habitat. The defining character is that Asynarchus larvae have dorsal chloride epithelia, while Limnephilus sp. do not. However, immature and poorly preserved animals can be difficult to tell apart. A. nigriculus has been studied extensively at The Rocky Mountain Biological Laboratory by Scott Wissinger and colleagues. Interestingly this species commonly cannibalizes its fellow larvae in the race to emerge from temporary habitats before they dry. Good LinksOn this website:Introduction to the Limnephilidae Other Websites: Photos, Map, Taxon Identifier Numbers - from the Global Biodiversity Information Facility Asynarchus nigriculus at GBIF Photos, Map, Museum specimens, DNA - Barcodinglife.org ReferencesAl Mousa,MDA 2020 Studies on the Odonata and Trichoptera of high-elevation lakes of northern Colorado and southern Wyoming. MS Thesis, Colorado State University, Fort Collins, Colorado. 187 pages. PDFQuote from pages 83-84: "Asynarchus nigriculus (Banks, 1908) was collected and recorded between 1934 and 2020 from 28 lentic localities (Fig. 3.6, Appendix 4) with an elevation range of 2,545-3,695m in Boulder (14), Clear Creek (3), Gilpin (1), Grand (1), Jackson (2), and Larimer (7) Counties. Wiggins (2014) noted that they collected larvae of this species in streams, ponds, and temporary ponds. The type locality of this species is Clear Creek County, Colorado (Rasmussen & Morse 2018). In a study of the caddisflies of the high-elevation lentic habitats in Colorado, Wissinger et al. (2003) noted that A. nigriculus was the most abundant species in both high-elevation autumnal habitats and vernal ponds." Al Mousa,MDA; Nachappa,P; Ruiter,DE; Givens,DR and Fairchild,MP 2022 Caddisflies (Insecta: Trichoptera) of montane and alpine lakes of northern Colorado (USA). Western North American Naturalist, 82(3), pp.563-576. PDF Quote from page 570: "Six limnephilids we encountered are considered regionally endemic to the Rocky Mountains (Table 2, Supplementary Material 1). Asynarchus nigriculus (Banks, 1908) was collected and recorded between 1934 and 2020 from 28 lentic localities across northern Colorado (Table 2, Supplementary Material 1). Wiggins (2014) collected larvae of this species in streams, ponds, and temporary ponds. The type locality of this species is Clear Creek County, Colorado (Rasmussen and Morse 2021), and, with the exception of a 1958 record from Maine, the taxon is largely confined to the central Rocky Mountains of Colorado, Wyoming, and Utah (Rasmussen and Morse 2021). In a study of the caddisflies of the high-elevation lentic habitats in Colorado, Wissinger et al. (2003) noted that A. nigriculus was the most abundant species in both high-elevation autumnal habitats and vernal ponds." Balik,JA; Leitz,C; Washko,SE; Cleveland,B; Krejsa,DM; Perchik,ME; Stogsdill,A; Vlah,M; Demi,LM; Greig,HS and Shepard,ID 2022 Species-specific traits predict whole-assemblage detritus processing by pond invertebrates. Oecologia, 199(4), pp.951-963. PDF Balik,JA; Taylor,BW; Washko,SE and Wissinger,SA 2018 High interspecific variation in nutrient excretion within a guild of closely related caddisfly species. Ecosphere, 9(5) p.e02205. PDF Banks,N 1908 Neuropteroid insects - notes and descriptions. Transactions of the American Entomological Society 34:255-267. Described as Anabolia nigricula.  
Demi,LM; Hughes,D and Taylor,BW 2022 Characterizing the role of phosphorus availability and periphytic algae in the food choice and performance of detritivorous caddisflies (Trichoptera: Limnephilidae). Freshwater Science, 41(1) 18-32. PDF Abstract: "Organisms that rely on detritus as their primary food source may face particularly strong nutritional constraints on growth and development, given the characteristically poor quality of detrital resources. In freshwater ecosystems, the low content of P in detritus often limits detritivore growth. Additionally, a growing body of evidence suggests the biochemical composition of algae, such as essential fatty acids, can limit aquatic detritivore growth. We investigated feeding preference and growth responses of common aquatic detritivores by performing paired feeding-preference and growth experiments on 4 species of larval caddisflies (Trichoptera) from the family Limnephilidae: Asynarchus nigriculus, Anabolia bimaculata, Limnephilus externus, and Ecclisomyia sp. We manipulated both the P content and epiphytic algal biomass of a common detrital food resource (decomposing sedge [Carex sp.]) by conditioning the detritus under 2 different light (ambient, shaded) and P (ambient [low], +P) regimes. We tested 3 hypotheses that describe feeding preferences and performance under different scenarios of P limitation, algal limitation, and co-limitation by P and algae. We observed evidence of preferential feeding behavior for each of the 4 taxa, with 2 species exhibiting preferences for conditioned detritus with high algal biomass and 2 for detritus from the +P treatments. We observed agreement between feeding preferences and performance (growth, growth efficiency, mortality) for only 2 taxa, with A. nigriculus exhibiting higher growth rates and growth efficiency on their preferred high- P detritus, and L. externus experiencing lower mortality when reared on their preferred high algal biomass detritus. These findings provide an initial step toward characterizing the feeding preferences and performance responses of aquatic detritivores to 2 potentially common nutritional constraints: detrital P and algal supply." Finn,DS and Poff,NL 2008 Emergence and flight activity of alpine stream insects in two years with contrasting winter snowpack. Artic, Antarctic, and Alpine Research 40(4)638-646. PDF Greig,HS and Wissinger,SA 2010 Reinforcing abiotic and biotic time constraints facilitate the broad distribution of a generalist with fixed traits. Ecology, 91(3) 836-846. PDF Abstract: "Many species are habitat specialists along environmental gradients as a result of contrasting selection pressures, but others maintain broad distributions along such gradients. Phenotypic plasticity explains the persistence of some generalists, but not the broad distributions of species with fixed traits. We combined comparative and experimental data to investigate the role of multiple selection pressures on the distribution of a cased caddisfly (Asynarchus nigriculus) across a pond permanence gradient in the Mexican Cut Nature Preserve, Elk Mountains, Colorado, USA. Rapid development in this species facilitates the exploitation of short-duration vernal pools. Comparative data document that slowly growing individuals die from desiccation, suggesting an ongoing selection for rapid development. Surprisingly, development is as fast or faster in long-duration, autumnal ponds where emergence occurs long before drying, and overlaps with the appearance of beetle (Dytiscus) predators. In field experiments we found that the last two instars of beetle larvae pose a significant mortality threat to Asynarchus, but that threat declines after caddisfly pupation. In natural populations, the caddisflies pupate and emerge just as large beetle instars appear in the ponds. Experimental manipulation of caddisfly size suggests that rapid development in autumnal ponds will both facilitate intraguild predation on other caddisflies and reduce Asynarchus cannibalism. Both types of caddisfly interactions should have a positive feedback effect on rapid development via a protein supplement to their detrital diet. All of these biotic time constraints should select for rapid Asynarchus development in autumnal habitats, despite relaxed drying time constraints. Asynarchus did not display flexible antipredator responses to beetles (no changes in activity rates, morphology, or development), suggesting that the traits that lead to rapid development are fixed, regardless of habitat type and presence of predators. We propose that different, but convergent, selection pressures across different habitat types have led to fixed specialized traits that enable a broad distribution along this environmental gradient. These selection pressures are dependent on the relative phenologies of interacting species and appear to trump the trade-offs between other types of physical and biotic constraints across habitats." Herrmann,SJ; Ruiter,DE and Unzicker,JD 1986 Distribution and records of Colorado Trichoptera. Southwestern Naturalist 31(4) 421-457. The authors show this species present in Gunnison County. Lund,JO; Wissinger,SA and Peckarsky,BL 2016 Caddisfly behavioral responses to drying cues in temporary ponds: implications for effects of climate change. Freshwater Science, 35(2), pp.619-630. PDF Abstract: " Aquatic organisms that live at high latitudes and elevations are especially vulnerable to climate-change-induced alterations in snowpack, snowmelt, and evaporation rates, all of which affect basin filling and drying dates. Extraordinarily early drying events in shallow ponds and wetlands at our study sites prompted us to conduct 2 mesocosm experiments to document how proximate cues of drying modify agonistic behaviors among larvae of the caddisfly, Asynarchus nigriculus. Larvae are mainly detritivores but can be extremely aggressive and engage in mob cannibalism, perhaps to obtain a dietary supplement that hastens escape from drying basins. In one experiment, we manipulated caddisfly density to simulate the effects of crowding during pond drying. In a 2nd experiment, we reduced water levels and manipulated a protein supplement that mimics the dietary benefits of cannibalism. We quantified the effects of those manipulations on aggressive behaviors that are precursors to cannibalism and on development time to pupation. Frequency and duration of agonistic encounters increased as a function of larval density and, independent of density, were higher in drying than nondrying treatments, especially in the absence of a protein supplement. Pupation occurred earlier in high- than low-density treatments and earlier with than without a protein supplement. In contrast, the timing of pupation was not accelerated in drying compared with nondrying treatments, which might reflect the extreme diel temperature fluctuations in drying ponds, hence suboptimal growth conditions. Our findings provide evidence that declining water levels and crowding serve as cues that enable caddisflies to adjust behavior and development in the face of habitat drying. Early drying events observed in recent years may exceed the limits of this flexibility and portend the demise of populations in temporary habitats that historically supported this species." 
McCullagh,BS; Wissinger,SA and Marcus,JM 2015 Identifying PCR primers to facilitate molecular phylogenetics in Caddisflies (Trichoptera). Zoological Systematics, 40(4) 459 PDFOláh,J; Andersen,T; Beshkov,S; Bilalli,A; Coppa,G and Kovács,T 2019 Lineage sorting by parameres in Limnephilinae subfamily (Trichoptera): with description of a new tribe, new genera and new species. Opuscula Zoologica (Budapest), 50, pp.3-98. PDF On page 18, Figure 45, there is an illustration of a A. nigriculus paramere. Schmid,F 1954 Le genre Asynarchus McL. (Trichopt., Limnoph.). Mitteilungen der Schweizerischen Entomologischen Gesellschaft 27:57-96. Reviews the adults of Asynarchus. Shepard,ID; Wissinger,SA and Greig,HS 2023 Contrasting short-and long-term outcomes of pairwise interactions between caddisflies at a hydrologically heterogeneous range margin. Freshwater Biology, 68(2), pp.202-211. PDF Abstract: "1. Climate change is leading many species to shift their geographical ranges. Species undergoing these range shifts often are moving into areas with heterogeneous abiotic conditions. Additionally, these range-shifting species will encounter resident species with whom they will compete for space and/or resources. However, the ways that these abiotic and biotic factors interact to influence the establishment and persistence of range-shifting species has received little attention. 2. Here, we conduct an in situ cage experiment examining how a local wetland hydroperiod gradient (i.e., temporary and semi-permanent ponds) and competition with a resident caddisfly species, Asynarchus nigriculus, influences the survival of the range-shifting species Limnephilus picturatus. We then use long-term survey data of population densities of these two species to determine whether pairwise interactions observed in the cage experiment translated into long-term dynamics. 3. The cage experiment revealed that A. nigriculus had a strong, negative effect on the survival of the range-shifting species L. picturatus, regardless of hydroperiod. However, we observed no relationship between the densities or occurrence of L. picturatus and A. nigriculus in long-term data for either temporary or semi-permanent ponds. 4. Our results suggest that landscape-level abiotic heterogeneity at range margins may not always be important for mediating antagonistic interactions between resident and range-shifting species. However, although an interaction appears ecologically significant in short-term field studies, broader context is needed to understand whether those types of interactions mediate species' distributions and abundance through time. 5. At face-value, our results from the field experiment and long-term data analysis did not align. This suggests that other factors such as additional competitive or trophic interactions may be more important drivers behind the population dynamics of this range-shifting species at its new upper-elevational limit." Shepard,ID; Wissinger,SA; Wood,ZT and Greig,HS 2022 Predators balance consequences of climate-change-induced habitat shifts for range-shifting and resident species. Journal of Animal Ecology, 91(2), pp.334-344. PDF Abstract: "1. While many species distributions are shifting poleward or up in elevation in response to a changing climate, others are shifting their habitats along localized gradients in environmental conditions as abiotic conditions become more stressful. Whether species are moving across regional or local environmental gradients in response to climate change, range-shifting species become embedded in established communities of competitors and predators. The consequences of these shifts for both resident and shifting species are often unknown, as it can be difficult to isolate the effects of multiple species interactions. 2. Using a model system of insects in high-elevation ponds in the Rocky Mountains of Colorado, we sought to disentangle the effects of predation and intraguild interactions on the survival and development of a semi-permanent pond resident caddisfly Limnephilus externus and the habitat-shifting caddis Asynarchus nigriculus that is being forced into semi-permanent ponds as temporary ponds dry too quickly to complete development. 3. We conducted a manipulative in-situ pond cage experiment in which L. externus and A. nigriculus caddisfly larvae in single-species treatments and together were exposed to the presence/absence of predatory Dytiscus diving beetle larvae. This approach allowed us to isolate the effects of intraguild interactions and predation on the survival and development of both the resident and habitat-shifting species. 4. We found that intraguild interactions had strong negative effects on the resident and habitat-shifting species. Intraguild interactions reduced the survival of the resident L. externus and increased the variation in survival of the shifting A. nigriculus. However, Dytiscus predators reduced these negative effects, stabilizing the community by increasing L. externus survival and reducing variation in A. nigriculus survival. We also found that intraguild interactions reduced L. externus biomass but resulted in increased A. nigriculus development. A. nigriculus development was also increased by predation. 5. Our results show that strong intraguild interactions between resident and shifting species are likely to have negative consequences for both species. However, the presence of predators reduces these negative consequences of the habitat shift on both the resident and the shifting species." Tigreros,N and Davidowitz,G 2019 Flight-fecundity tradeoffs in wing-monomorphic insects. Advances in insect physiology, 56, pp.1-41. PDF Wissinger,SA 2004 Population fluctuations in caddisflies inhabiting high-elevation wetlands in central Colorado. Presented at the NABS Annual meeting, Vancouver, British Columbia, in Population Ecology 2 Abstract Wissinger,SA; Brown,WS and Jannot,JE 2003 Caddisfly life histories along permanence gradients in high altitude wetlands in Colorado (U.S.A.). Freshwater Biology 48(2). PDF (427 Kb) "SUMMARY 1. Larvae of cased caddisflies (Limnephilidae and Phryganeidae) are among the most abundant and conspicuous invertebrates in northern wetlands. Although species replacements are often observed along permanence gradients, the underlying causal mechanisms are poorly understood. In this paper, we report on the distributional patterns of caddisflies in permanent and temporary high-altitude ponds, and how those patterns reflect differences in life history characteristics that affect desiccation tolerance (fundamental niches) versus constraints related to biotic interactions (realised niches). 2. Species (Hesperophylax occidentalis and Agrypnia deflata) that were encountered only in permanent ponds are restricted in distribution by life history (no ovarian diapause, aquatic oviposition, and/or inability to tolerate desiccation). Although the egg masses of H. occidentalis tolerate desiccation, the larvae leave the protective gelatinous matrix of the egg mass because adults oviposit in water. 3. Three species (Asynarchus nigriculus, Limnephilus externus and L. picturatus) have life history characteristics (rapid larval growth, ovarian diapause and terrestrial oviposition of desiccation-tolerant eggs) that should facilitate the use of both permanent and temporary habitats. However, A. nigriculus is rare or absent in most permanent ponds, and L. externus and L. picturatus are rare or absent in most temporary ponds. Experimental data from a previous study on the combined effects of salamander predation and interspecific interactions among caddisflies (e.g. intraguild predation) suggest that biotic interactions limit each species to a subset of potentially exploitable habitats. 4. Many wetland invertebrates exhibit species replacements along permanence gradients, but few studies have separated the relative importance of the effects of drying per se from the effects of biotic interactions. Our results emphasise the complementary roles of comparative data on life histories and experimental data on competition and predation for understanding invertebrate distributions along permanence gradients." Wissinger,SA; Eldermire,C and Whissel,JC 2005 The role of larval cases in reducing aggression and cannibalism among caddisflies in temporary wetlands. Wetlands 24(4) 777-783. PDF Abstract: " Larvae of wetland caddisflies supplement their detrital diets with animal material. In some species this supplement is obtained by preying on other caddisflies. In this study, we conducted a series of laboratory experiments to a) compare intraspecific aggression and the propensity for cannibalism among six caddisfly species that occur along a gradient from vernal to autumnal to permanent high-elevation wetlands, and b) determine the importance of cases in preventing or reducing cannibalism and intraguild predation. We predicted that cannibalism and overall levels of aggression should be highest in species that occur in temporary habitats. We found that all of the species that use temporary habitats (Asynarchus nigriculus ,Hesperophylax occidentalis, Limnephilus externus, Limnephilus picturatus, Limnephilus secludens) were extremely aggressive towards and cannibalized conspecifics without cases. Species that typically occur in short-duration temporary wetlands were more aggressive than those in long-duration temporary wetlands. Cases prevented cannibalism in four of these temporary-habitat species, and reduced cannibalism among Asynarchus larvae. The latter species occurs in extremely ephemeral habitats where cannibalism provides a dietary supplement that probably facilitates emergence before drying. Asynarchus also preys on Limnephilus spp., and we found that cases dramatically reduced vulnerability to intraguild predation. Larvae of Agrypnia deflata, a species that occurs only in permanent wetlands, were least aggressive and rarely cannibalized conspecifics. Our results are consistent with the hypothesis that intraspecific aggression and the potential for cannibalism are highest in species that live in habitats with developmental time constraints. Many wetland invertebrates face developmental time constraints and selection for aggression in temporary habitats should be especially strong for taxa that rely on animal material to supplement a mainly detrital diet." Wissinger,SA; Sparks,GB; Rouse,GL; Brown,WS and Steltzer,HM 1996 Intraguild predation and cannibalism among larvae of detritivorus caddisflies in subalpine wetlands. Ecology 77 (8) 2421-2430. Read online Abstract: "Comparative data from subalpine wetlands in Colorado indicate that larvae of the limnephilid caddisflies, Asynarchus nigriculus and Limnephilus externus, are reciprocally abundant among habitats-Limnephilus larvae dominate in permanent waters, whereas Asynarchus larvae dominate in temporary basins. The purpose of this paper is to report on field and laboratory experiments that link this pattern of abundance to biotic interactions among larvae. In the first field experiment, growth and survival were compared in single and mixed species treatments in littoral enclosures. Larvae, which eat mainly vascular plant detritus, grew at similar rates among treatments in both temporary and permanent habitats suggesting that exploitative competition is not important under natural food levels and caddisfly densities. However, the survival of Limnephilus larvae was reduced in the presence of Asynarchus larvae. Subsequent behavioral studies in laboratory arenas revealed that Asynarchus larvae are extremely aggressive predators on Limnephilus larvae. In a second field experiment we manipulated the relative sizes of larvae and found that Limnephilus larvae were preyed on only when Asynarchus larvae had the same size advantage observed in natural populations. Our data suggest that the dominance of Asynarchus larvae in temporary habitats is due to asymmetric intraguild predation (IGP) facilitated by a phenological head start in development. These data do not explain the dominance of Limnephilus larvae in permanent basins, which we show elsewhere to be an indirect effect of salamander predation. Behavioral observations also revealed that Asynarchus larvae are cannibalistic. In contrast to the IGP on Limnephilus larvae, Asynarchus cannibalism occurs among same-sized larvae and often involves the mobbing of one victim by several conspecifics. In a third field experiment, we found that Asynarchus cannibalism was not density-dependent and occurred even at low larval densities. We hypothesize that Asynarchus IGP and cannibalism provide a dietary supplement to detritus that may be necessary for the timely completion of development in these nutrient-poor, high-elevation wetlands." Wissinger,SA; Whiteman,HH; Sparks,GB; Rouse,GL and Brown,WS 1999 Foraging trade-offs along a predator-permanence gradient in subalpine wetlands. Ecology 80, 2102-2116. PDF Abstract: "We conducted a series of field and laboratory experiments to determine the direct and indirect effects of a top predator, the tiger salamander (Ambystoma tigrinum nebulosum), on larvae of two species of limnephilid caddisflies (Limnephilus externus and Asynarchus nigriculus) in subalpine wetlands in central Colorado. Asynarchus larvae predominate in temporary wetlands and are aggressive intraguild predators on Limnephilus larvae, which only predominate in permanent basins with salamanders. We first conducted a field experiment in mesocosms (cattle tanks) to quantify the predatory effects of different life stages of salamanders on the two caddisfly species. Two life stages of the salamanders (larvae and paedomorphs) preferentially preyed on Asynarchus relative to Limnephilus. Subsequent laboratory experiments revealed that high Asynarchus activity rates and relatively ineffective antipredatory behaviors led to higher salamander detection and attack rates compared to Limnephilus. In a second field experiment (full factorial for presence and absence of each of the three species), we found that salamander predation on Asynarchus had an indirect positive effect on Limnephilus: survival was higher in the presence of salamanders + Asynarchus than with just Asynarchus. In the laboratory we compared the predatory effects of salamanders with and without their mouths sewn shut and found the observed indirect positive effect on Limnephilus survival to be mainly the result of reduced numbers of Asynarchus rather than salamander-induced changes in Asynarchus behavior. We argue that indirect effects of predator-predator interactions on shared prey will be mainly density-mediated and not trait-mediated when one of the predators (in this case, Asynarchus) is under strong selection for rapid growth and therefore does not modify foraging behaviors in response to the other predator. The reciprocal dominance of Limnephilus and Asynarchus in habitats with and without salamanders probably reflects a trade-off between competitive superiority and vulnerability to predation. The high activity levels and aggressiveness that enable Asynarchus to complete development in temporary habitats result in strong asymmetric competition (via intraguild predation) with Limnephilus. In permanent habitats these same behaviors increase Asynarchus vulnerability to salamander predation, which indirectly benefits Limnephilus. This and previous work implicate salamanders as keystone predators that exert a major influence on the composition of benthic and planktonic assemblages in subalpine wetlands." Wissinger,SA; Steinmetz,J; Alexander,JS and Brown,WS 2004 Larval cannibalism, time constraints, and adult fitness in caddisflies that inhabit temporary wetlands. Oecologia 138, 39-47. PDF Abstract: "The fitness of non-feeding adult insects depends on energy accumulated during the larval stage. Larvae of the caddisfly Asynarchus nigriculus primarily feed on plant detritus, but supplement their diet with animal material obtained through cannibalism. Habitat drying constrains development in many populations of this species, and we hypothesized that cannibalism should accelerate development to facilitate timely metamorphosis. We manipulated larval diets in a field experiment by supplementing detritus with animal material, and in a laboratory experiment by varying animal material and detritus quality (conditioned vs unconditioned). We measured the effects of dietary manipulation on larval and pupal growth and development, the timing of metamorphosis, and adult fitness correlates. The results of the laboratory experiment suggest that this species can metamorphose with a detritus-only diet, but development is extremely protracted. In the field experiment, individuals with animal material in their diet had higher larval survival, shorter larval and pupal development times, and earlier emergence dates (7-10 days), than those without a supplement. This delay in emergence should have important effects on survival in natural populations where the difference between desiccation and successful emergence can be only a few days. Dietary supplementation also affected adult body mass (30-40% increase), female fecundity (30% more eggs), and proportional allocation to different adult body parts. Our results are consistent with recent growth-development models that predict coupled (earlier emergence and larger adults) rather than tradeoff responses (earlier emergence and smaller adults) to pre-threshold manipulation of larval diets. Many detritivorous aquatic insects supplement their diets with animal material, and our data provide evidence that this supplementation can have strong effects on fitness. This type of dietary supplementation should be especially important for taxa that do not feed as adults, and in temporary habitats that impose time constraints on larval development." Wissinger,SA; Whissel,J; Eldermire,C and Brown,W 2006 Predator defense along a permanence gradient: roles of case structure, behavior, and developmental phenology in caddisflies, Oecologia:1-12. PDF (311 KB) Abstract: "Species replacements along freshwater permanence gradients are well documented, but underlying mechanisms are poorly understood for most taxa. In subalpine wetlands in Colorado, the relative abundance of caddisfly larvae shifts from temporary to permanent basins. Predators on caddisflies also shift along this gradient; salamanders (Ambystoma tigrinum nebulosum) in permanent ponds are replaced by predaceous diving beetles (Dytiscus dauricus) in temporary habitats. We conducted laboratory and field experiments to determine the effectiveness of caddisfly cases in reducing vulnerability to these predators. We found that larvae of a temporary-habitat caddisfly (Asynarchus nigriculus) were the most vulnerable to salamanders. Two relatively invulnerable species (Limnephilus externus, L. picturatus) exhibited behaviors that reduced the likelihood of detection and attack, whereas the least vulnerable species (Agrypnia deflata) was frequently detected and attacked, but rarely captured because cases provided an effective refuge. Vulnerability to beetle predation was also affected by cases. The stout cases of L. externus larvae frequently deterred beetle larvae, whereas the tubular cases of the other species were relatively ineffective. Two of these vulnerable species (A. nigriculus and L. picturatus) often co-occur with beetles; thus, case construction alone is insufficient to explain patterns of caddisfly coexistence along the permanence gradient. One explanation for the coexistence of these two species with beetles is that they develop rapidly during early summer and pupate before beetle larvae become abundant. One species (L. picturatus) pupates by burying into soft substrates that serve as a refuge. The other (A. nigriculus) builds stone pupal cases, which in field experiments, more than doubles survival compared to organic pupal cases. The combined results of these experiments suggest that caddisfly distributions along permanence gradients depend on a suite of primary and secondary predator defenses that include larval and pupal case structure, predator-specific escape behaviors, and the phenology of larval development." Zuellig,RE; Heinold,BD; Kondratieff,BC and Ruiter,DE 2012 Diversity and Distribution of Mayflies (Ephemeroptera), Stoneflies (Plecoptera), and Caddisflies (Trichoptera) of the South Platte River Basin, Colorado, Nebraska, and Wyoming, 1873-2010. U.S. Geological Survey Data Series 606, 257 p. PDF - caution 46MB Quote from page 83: "The type locality for this species is Clear Creek, Colorado (Banks, 1908). Larvae usually are cannibalistic just before emergence from temporary ponds before they dry up in late summer (Wissinger and others, 2003; Wissinger and others, 2004)." The elevation range is 8,150-12,750 feet and the adults emerge from July-September. Photos of chloride epitheliaFinding the elusive chloride epethilia on a Limnephilid caddisfly can be a triumphant moment at the microscope. I hope these photos help people know what to look for. Look for the shiny horizontal oval in about the center of the photo. Notice the faint dark edge or border. While this photo is not the best, it is fairly similar to what you see under an average microscope.  Closeup of a different chloride epethilia on the same animal. |