Tristin Wright
EVS 495
Professor Amy Long
10/19/2018
Senior Project Skeleton Draft
Introduction
This website is a general taxonomic guide to aquatic insect species throughout North Carolina as well as supplemental information about where the species can be found across the state. This website includes a variety of the most commonly found aquatic insects including aquatic beetles (Coleoptera), caddisflies (Trichoptera), stoneflies (Plecoptera), mayflies (Ephemeroptera), and non-biting midges (Chironomidae) as well as other aquatic organisms. Along with photographs of each species, other information will include how these various insects play a role in their aquatic ecosystem and what purposes they are studied for. Aquatic insects are an incredibly diverse group that occupy various streams, rivers, and other water bodies across North Carolina. These insects can be studied and used as bioindicators to learn about water quality, health of aquatic biota, and other ecosystem effects from land use. Gaining the knowledge of which species occupy each aquatic ecosystem throughout the state and when they do can help us gain an understanding of long- and short-term anthropogenic changes that have been brought to it. This website serves as a quick guide for environmental scientists, biologists, students, and anyone that wishes to learn more about the various creatures that occupy our aquatic systems.
The world of aquatic insects is fascinating on its own, with thousands of species dispersed all around the world and a particular abundance of interesting organisms throughout water bodies in North Carolina. While traditional water quality assessments can provide data such as dissolved oxygen content and temperature, Benthic Macroinvertebrates can provide additional and often more informative data on impacts from habitat loss due to their sensitivity to chemical, physical, and biological changes to their ecosystem.
EPT data specifically refers to data taken from sampling Ephemeroptera, Plecoptera, and Trichoptera orders and are particularly beneficial to water quality monitoring due to their low tolerances to pollutants and wide presence throughout North Carolina freshwater streams and water bodies .
EPT taxa richness is often measured with The EPT Biotic Index (EPTBI), which is well suited for studying the impact of in-stream sediments, as well as the North Carolina Biotic Index (NCBI), a reliable indicator of stream chemistry and habitat quality .
While benthic macroinvertebrates include non-insect organisms like crustaceans and gastropods, insects variants are most often studied simply due to their numbers and species diversification throughout benthic environments in North Carolina and around the world .
Macroinvertebrates are also beneficial to stream analyses because they can provide assessments at more specific regions since they are typically less mobile than fish and other aquatic organisms
Trichoptera:
Also known as Caddisflies, this species is frequently used as a bioindicator to detect for pollution in an area due to their low tolerance for pollutants (BugGuide, 2004). A presence of Caddisfly larvae can be an indicator of good water quality, while signs of pollution can be seen in areas where Caddisflies had been previously recorded but can no longer be found (BugGuide, 2004). Order Trichoptera can be broken down into two main groups known as net spinners and casemakers, one being a free-floating form and the other producing its own enclosure out of various materials (WPWA, n.d.. While casemaker larvae produce portable enclosures and are herbivores, feeding on periphyton (freshwater organisms attached to submerged surfaces), net spinners or free floating Trichoptera create nets and retreats to assist predation of other arthropods (WPWA, N/A). Net spinner forms often create intricate nets and place them in an area of fast-moving water to catch prey, clinging onto nearby twigs, leaves, and rocks set firmly in the stream (Winborne, 2003)
All caddisfly larvae pupate in a completely closed cocoon (WPWA, n.d.). Ranging in size from 1.5mm to 40mm, cased Caddisflies can help be identified by examining the shape of their case as well as what materials they are comprised of, which are indicative to the family and/or genus of the insect (Cotinis, 2004). Trichoptera feature three pairs of thoracic legs with simple eyes, chewing mouth parts, a single tarsal claw, very short antennae, and fleshy prolegs on the last abdominal segment (Cotinis, 2004).This source also includes that a large number of larvae perform respiration through the integument as well as single or branched gills that are located on the abdominal segments.
Caddisflies are found worldwide especially throughout North America and comprise of over 1400 species, with the greatest diversity residing in cool and well oxygenated lotic (rapidly moving) water, although can also be found in ponds and other lentic bodies of water (WPWA, n.d.). Case making Caddisflies will often appear as a floating twig in a sample dish, with their case composition being an indicator of what type of water area the species resides in (Winborne, 2003). This source includes that casemaker Caddisflies with cases comprised of organic matter like twigs and large leaves are restricted to slower moving water flows, while species with heavier contents like pebbles and sediment can access more rapidly moving water bodies (Winborne, 2003).
Chironomidae:
Chironomidae (or Diptera) are a diverse group of flies commonly known as non-biting midges whose aquatic larval form is so widely diverse it occupies almost every ecological niche among freshwater aquatic environments throughout the state . The source includes that their larval form, known as bloodworms, are usually the most widely available and diverse species among North Carolina’s freshwater aquatic habitats. It adds that while the abundance of these organisms can help create more specific bioassessments to an ecosystem, it also has made identifying difficult for this taxon due to the sheer number of species that could be present in one system. Chironomidae are still regarded as bio indicators, though, as some species are identified as indicators of high water quality and others as indicators of low water quality.
Identification
While Non-Biting Midges resemble mosquitos, they possess long and narrow without scales along with a long, feathery plumose present in males. Diptera spend the majority of their life in their larval form with an adult life span so short they do not even need to feed throughout it. Aquatic Diptera larvae are the most morphologically diverse among the included taxa, and can
generally be defined by their elongated, worm like bodies and their lack of true legs, moving through water with a wiggling locomotion. Species may have prolegs, though, and all species feature a thorax and abdomen made of soft, thin skin and lacking wing pads (WPWA, n.d.). Non-biting midge larvae are most commonly sorted and identified by observing physical features such as anal setae, anal tubules compared to their posterior parapods, and whether ventral or lateral tubules are present on the abdominal segment. Habitat and Distribution
Non-biting midges are found worldwide and typically live in damp areas or near bodies of freshwater water as the majority of their life is spent in water in their larval form but can also be found in estuarine and saltwater environments.
Plecoptera, also known as Stoneflies, are freshwater aquatic insects that spend the majority of their lives in its nymph stage and are commonly used for bait in flyfishing as they are a premier food item for freshwater trout across the Southeast United States and throughout Appalachian Mountain streams. Plecoptera are a member of the EPT group that is most frequently used to analyze water quality due to their exceptional susceptibility to pollutants, often being succeeded by more pollution-tolerant benthic macroinvertebrates. Plecoptera in particular are extremely sensitive to pollutants, requiring a high presence of oxygen and clean, cool waters. Stoneflies were even utilized to determine temporal changes in the Southern Appalachian Mountain catchment due to their intolerance and diverse fauna in freshwater streams. The article states that this was done by examining the elevational distribution of various Plecoptera groups at increasing elevations along the Southern Appalachian Mountains to detect temporal change over time.
IdentificationStoneflies consist of three main groups including quick-crawling predators, roach-shredders, and fragile detritivores. This source describes that Stoneflies are often confused with Mayflies, but can be told apart through their location of their gills under the thorax, two tails, and two sets of wing pads. The gills are filamentous, with the body being flattened and elongated with two long cerci. Plecoptera also feature compound eyes, chewing mouth parts, and
Habitat and distribution
Stoneflies reside in cooler, more temperate parts of the world, with nymphs being found in resting structures like under rocks, in cracks in logs, and embedded in detritus. The are most diverse throughout North America, and require fast moving, highly oxygenated streams, and are usually the top invertebrate predator within the ecosystem.
Identification
Often confused with mayflies due to similar tail structure, but dragonflies can be told apart from Damselflies and Mayflies with having flatter, thicker tail segments than the previous two. Both are predators, with dragonflies have shorter bodies and Damselflies having long bodies with tall, gangly legs. Odonatae are typically top predators in their aquatic system and are known to be cannibalistic towards both adult and larval forms. Larval forms move via rectal jet propulsion and are “beneficial predatorsâ€, feeding on other invertebrates considered pests. All members of order Odonota have wing pads present on the thorax, three pairs of segmented legs, and two claws, with a body either long and stout or a flattened oval shaped. Damselflies feature three flat and elongate gills on the end of the abdomen, while Dragonflies feature three short, pointed structures forming a pyramid shaped valve on the abdomen.
Habitat and distribution
Predominantly found along rooty masses along sides of creeks in North Carolina, Dragonflies and Damselflies can also be found throughout the world with higher diversity in warmer climates . Odonata prefer different sediment types from species to species, with species that prefer the same sediment nearly always being found together during sampling .
Ephemeroptera, also known as Mayflies, are accounted for worldwide and throughout North America. The species inhabits a zoogeographical region encompassing North America extending south to northern Mexico, or otherwise known as Nearctic Regions. Palearctic realms generally familiarize with faunas of Nearctic regions; both sharing various plant and animal species. While commonly referred to as a spinner; an adult Mayfly is utilized as bait in fly fishing. “North Carolina, here established as a state with one of the most diverse mayfly faunas in North Americaâ€. The previous lack of supported and consistent data among North Carolinian species has been alleviated. Taking this into account, Mayflies are now being considered and examined resulting in latterly released published data. However, there are specific species of mayflies that present strenuous and challenging analysis regarding identification of larvae to species. This Inevitably supplies invalid and unreliable data. Of the sparse data collected, historical records constructed on adult males are the most reputable for presumed genera. “Some emerge in late April (earlier in the south) but the greatest numbers first appear in May, and adults may be seen until September in the north; later, and perhaps around the year, in the far southâ€. The immature configuration of this invertebrate consumes organic matter particles such as; plant matter or nonflowering plants exhibited by algae. Algae and debris collect in flowing water by linking to rocks and other supporting surfaces where plants, algae, or particular animals occupy and flourish. The adult counterpart of this species is incapable of ingestion due to non-functioning mouthparts. . Mayflies consist of “675 species in 20 families, evolved 280-300 mya (carboniferous)†. Identification
Pre-adult Mayflies exhibit a cloudy presentation where their bodies appear subdued and partially mature. The invertebrate’s protuberances or appendages are typically shorter in length, but contrarily compare to imago. Mayfly larvae characteristics include: “body elongate, flattened or cylindrical, usually greenish or browning but color varies according to the type of food eaten; legs long; antennae short; abdomen with later plate-like gills and usually three long thin tail projections (cerci)â€. Aquatic form or pre- adult Ephemeroptera are constituted of three caudal fibrils, amalgamation of gills on abdominal divisions, one tarsal bone or claw, and emerging wing pads. “Primarily grazers and collector-gatherers (algae and detritus), most are herbivores or detritivoresâ€.
Habitat and distribution
Numerous Mayflies necessitate lower water temperatures in return for a high dissolved oxygen concentration. Even so, few can tolerate relatively low dissolved oxygen environments. Mayflies are predominantly originated in cooler environments and prefer smaller and cleaner tributaries such as headwater streams where they naturally Inhabit and situate themselves in still, fresh water.
Conclusion:
Knowing the water quality and ecosystem health of an aquatic system is an essential tool for scientists to gain a better understanding of the long-term health of an ecosystem or area. Aquatic insects can play a critical role as bioindicators and this guide will help identify which species are in any aquatic system throughout North Carolina. Further uses of this guide could help gain a better understanding of local aquatic insects for educational, scientific, or business-related practices.
References
W. (n.d.). Aquatic Benthic Macroinvertebrates as Water Quality Indicators. Retrieved from http://www.wpwa.org/documents/education/Biological sampling.pdf
Bonner, L. A., Hayes, R. L., Lister, J. L., Myer, P. A., & Wolf, J. R. (2009). Rapid Bioassessment of Crabtree Creek (Wake County, North Carolina) Using Macroinvertebrate and Microbial Indicators. Journal of Freshwater Ecology,24(2), 227-238. doi:10.1080/02705060.2009.9664287
Epler, J. H., Ph. D. (n.d.). IDENTIFICATION MANUAL FOR THE LARVAL CHIRONOMIDAE (DIPTERA) OF NORTH AND SOUTH CAROLINA. Retrieved from https://files.nc.gov/ncdeq/Water Quality/Environmental Sciences/BAU/Benthos Reference/intro.pdf
Mcnett, J. K., Hunt, W. F., & Osborne, J. A. (2010). Establishing Storm-Water BMP Evaluation Metrics Based upon Ambient Water Quality Associated with Benthic Macroinvertebrate Populations. Journal of Environmental Engineering,136(5), 535-541. doi:10.1061/(asce)ee.1943-7870.0000185
Potter, K., Cubbage, F., & Schaberg, R. (2005). Multiple-scale landscape predictors of benthic macroinvertebrate community structure in North Carolina. Landscape and Urban Planning,71(2-4), 77-90. doi:10.1016/s0169-2046(04)00028-3
Tullos, D. D., & Neumann, M. (2006). A qualitative model for analyzing the effects of anthropogenic activities in the watershed on benthic macroinvertebrate communities. Ecological Modelling,196(1-2), 209-220. doi:10.1016/j.ecolmodel.2006.02.018
Cotinis (2004). Order Trichoptera – Caddisflies. Retrieved from https://bugguide.net/node/view/15740
Winborne, F. B. (2003). A Guide to Streamwalking. Retrieved from https://files.nc.gov/ncdeq/Water Resources/files/streamwatch/A_Guide_to_Streamwalking.pdf
C. (n.d.). WNC Stream Monitoring. Retrieved from https://cwfnc.org/get-involved/volunteer/wnc-stream-monitoring/
Maxted, J. R., Barbour, M. T., Gerritsen, J., Poretti, V., Primrose, N., Silvia, A., . . . Renfrow, R. (2000). Assessment framework for mid-Atlantic coastal plain streams using benthic macroinvertebrates. Journal of the North American Benthological Society, 19(1), 128-144. doi:10.2307/1468286