Sunderland 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: Diptera
FAMILY: Tipulidae
GENUS: Dicranota

Dicranota can be distinguished by the two tails and the comb feet, featured below. There are usually 5 pairs of prolegs on the abdomen with combs on them. In addition, the posterior portion of the abdomen often has a slight swelling. SMC

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: 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.

ORDER: Ephemeroptera
FAMILY: Baetidae 
GENUS: Baetis 

This mayfly has three "tails" and a unique head shape. Its gills are oval shaped and insert dorsally. The wing pad shape is an obvious characteristic. More mature nymphs have long, dark wing pads. 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, called setae. SMC

ORDER: Plecoptera
FAMILY: Leuctridae
GENUS: Leuctra

Among our most common stoneflies, this family is fairly slender by stonefly standards.  The divergent wing pads are a helpful characteristic. Leuctridae  are similar in overall shape to the Capniidae; however, Leuctridae often do not have pleural folds. If they are present, they only extend from abdominal segments 1-7.  Leuctra  are recognized by abdominal terga with posterior fringes of short hairs and last few segments with longer hairs. NABS

ORDER: Trichoptera
FAMILY: Hydropsychidae
GENUS: Cheumatopsyche

Cheumatopsyche has a forked foretrochantin (as does Ceratopsyche). The foretrochantin is the projection at the uppermost portion of the front leg closest to the head. The leg may need to be pulled away from the body to expose this feature.

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.

Cheumatopsyche have only 2 types of hair on the abdomen: long thin plain hairs and thicker club hairs, which are narrow close to the body and widen out at the distal end. Paired sclerites on the ninth abdominal segment are notched. SMC

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ORDER: Plecoptera
FAMILY: Pteronarcyidae
GENUS: Pteronarcys
 

Pteronarcyidae have branching gills from the bases of their legs as well as from the first abdominal segments. In stoneflies of the Pteronarcys genus, branched gills on the abdomen are only present on the first two segments.