|
|||||||
|
|
|||||||
|
|
|
|
|
|
|
||
|
Site codes explained and mapped (under mapping resources tab) |
|||||||
Elmore BranchThese are the ten most common macroinvertebrates found in samples from Elmore Branch. |
|
ORDER: Ephemeroptera
This mayfly has three "tails" and a unique head shape. Its gills are oval shaped and insert dorsally. More mature nymphs have long, dark wing pads. SMC |
ORDER: Diptera
Midge larvae tend to be the most common macroinvertebrate at our sites. As with other Diptera, there are no true jointed legs. Chironomidae do have a pair of prolegs at each end and preserved individuals tend to curl into a 'C'. Identification past family requires slide-mounted heads. We have seen philopotamid caddisflies misidentified with the chironomids and we suspect that that happens when samples are being sorted from trays. Under a microscope, six prominent legs can be seen on members of the family Philopotamidae. |
ORDER: Trichoptera Chimarra are distinguished from the other Philopotamidae by a prominent asymmetrical notch in the frontoclypeus as well as a prominent process on the femora which bears a single hair (seta). SMC |
ORDER: Trichoptera Ceratopsyche has a forked foretrochantin. The foretrochantin is the projection at the uppermost portion of the foreleg. The leg may need to be pulled away from the body to expose this feature. Ceratopsyche have a large pair of sclerites underneath the prosternum. Note: the large single sclerite is the prosternal plate. SMC
|
|
ORDER:
Ephemeroptera This mayfly has unique long hairs on its forelegs as the main distinguishing characteristic (allowing anyone keying to move through quickly). Carefully observe the limbs because such hair can be matted down and therefore hidden in preserved wet specimens. The body of Isonychia is slim and "minnow-like" when observed dorsally. In specimens we collected, they were commonly brown and substantial in length and width as compared to the very common Baetidae. Some individuals are immature, but upon closer inspection one can see the setae on the forelegs. |
ORDER: Trichoptera Potamyia, like Cheumatopsyche, have a small or inconspicuous pair of sclerites under the prosternal plate that are difficult to see. Contrast that with the larger pair of sclerites found on Ceratopsyche. To access sclerites, it's best to gently pull the pronotum and mesonotum in opposite directions. Note: the large single sclerite is the prosternal plate. Posterior margins of sclerites on abdominal sternum 9 are entire (there are no notches). The foretrochantin may or may not be forked, and there is a prominent anteriomedian projection on the anterial ventral apotome of the head. |
ORDER: Coleoptera The larvae of Stenelmis, as in Ordobrevia, have a sternum on the ventral side of the pronotum. The main difference between the two genera is in the antennae- the second segment is less than twice as long as the first in Stenelmis. The adult Stenelmis has a clear separation between the thorax and abdomen as well as a more distinctly separate head as compared to other genera. SMC |
ORDER: Trichoptera |
|
ORDER: Diptera Creeping welts or broad tubercles are found on this Tipulidae. No spiracles are present, but the surface may appear roughened under the microscope. |
ORDER:
Ephemeroptera This is the only Heptageniidae genus present in this area with two tails! |
The images are not a substitute for keying, but should serve as an aid in identifying common macroinvertebrates in samples.
| Feedback - Partner schools: send us specimens not included above. Taxonomists: click to email: Declan McCabe |
| This
site is supported by Vermont EPSCoR grant from the National Science
Foundation (EPS #0701410). ©2008 Saint Michael's College One Winooski Park, Colchester, Vermont, USA 05439 | 802.654.2000 | Privacy Policy |