Seymour Brook

ORDER: Diptera
FAMILY: Chironomidae

 Midge larvae tend to be the most common macroinvertebrate at our sites.  As with other Diptera, there are no true jointed legs.  Chironomids 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 the philopotamids.

ORDER: Coleoptera
FAMILY: Elmidae
GENUS: Stenelmis

Riffle beetles appear in the streams as adults and larvae. The larvae of Stenelmis have a sternum on the ventral side of the pronotum.

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

PHYLUM: Annelida
CLASS: Oligochaeta

Aquatic earthworms lack legs and are characterized by having 20 or more segments. Unlike leeches, they lack a suction disk.

NABS
ORDER: Trichoptera
FAMILY: Hydropsychidae

This family of net-spinning caddisflies is very abundant at several sites.  They are important filtering collectors and are quite common at urban and agricultural sites where particles of organic material can be important food resources.  Genus-level identification is possible for mature specimens and we will include the genera we found at your site if possible.  In general we commonly find Cheumatopsyche, Ceratopsyche, and Hydropsyche.

When using the key, some features that are challenging to see are the forked trochantin and the paired sclerites in the folds between segments.  Keep in mind that with smaller specimens, genus-level ID may not be possible.

ORDER: Coleoptera 
FAMILY: Elmidae
GENUS: Optioservus

The larvae of Optopservus have a closed coxae, as determined by the straight definition between segments on the ventral side of the pronotum.

The adult Optioservus have a compact appearance, especially the head and thorax. There are also dorsal ridges and a characteristic diamond-shaped feature observable in the dorsal view. SMC

ORDER: Coleoptera
FAMILY: Psephenidae
GENUS: Psephenus

The true "water penny" is commonly found in the waters sampled. Psephenus has a rounded shape with relatively smooth edge. The false water penny, whose edges are serrated, has a more oval appearance. The gills on the ventral surface are found only in the true water pennies. SMC

ORDER: Trichoptera
FAMILY: Philopotamidae
GENUS: Chimarra

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

NABS
ORDER: Trichoptera
FAMILY: Hydropsychidae
GENUS: Hydropsyche

Hydropsyche share most characteristics with Ceratopsyche, including the sclerites in the intersegmental folds. Hydropsyche are distinguished from Ceratopsyche by the presence of scale hairs and minute spines on the three most posterior abdominal segments. SMC

ORDER: Ephemeroptera
FAMILY: Baetidae 

This family of mayfly is characterized by antennae longer than the width of their head and a notch in their labrum. The most common genus we found was Baetis.
NABS

ORDER: Diptera
FAMILY: Tipulidae
 

The majority of fly larvae in the Tipulid family were found to be from the genera Antocha and Molophilus.