Most common macroinvertebrates found during the Vermont EPSCoR Streams Project.

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.

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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: 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.
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ORDER: Coleoptera
FAMILY: Elmidae

We found adults and larval riffle beetles in the genera Stenelmis and Optioservus.  The adults are clearly beetles, but the larvae can easily be confused with other orders. The forward pointing tooth on the front end of the larvae as described in the key can be a challenge to see.

ORDER: Diptera
FAMILY: Simuliidae

What's not to like about blackflies?  Our second most common dipteran.  Rather like a bowling pin with hands attached at the head end.  We have not identified them past family at this point, but it is in the long-term plan.
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ORDER: Trichoptera
FAMILY: Philopotamidae

Our next most common caddisfly family is once again a net-spinning filtering collector.  A casual observer might sort them with the chironomids, but a close look reveals six jointed legs.  The faint white 'T' shaped labrum extending from the front of the head past the mandibles is diagnostic for the family (it is sometimes withdrawn and hard to see).  Chimara is the most common genus we encountered.   The asymmetrical notch gets us to genus.  Dolophilodes is also common. SMC

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: Ephemeroptera
FAMILY: Ephemerellidae
GENUS: Drunella

The mayfly Drunella is distinguished by its large femoral “biceps” on the front legs. The body rests in one plane with the biceps at the same level as the head and junction with the thorax.

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: Diptera
FAMILY: Tipulidae
GENUS: Antocha

This small dipteran in the cranefly family is quite common.  It is distinguished from most other dipterans we found by the 'creeping welts' that appear as prominent dark stripes along the abdomen.  The dark head is usually partly exposed; however, it can be pulled back into the thoracic cavity during preservation.
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ORDER: Coleoptera
FAMILY: Dytiscidae
GENUS: Dytiscus

We found large numbers of small larvae in the Monroe Brook drainage in particular.  Don't let the paired claws and prominent 'tails' tempt you to think 'stonefly'; these tails are far less segmented than Plecoptera tails. The head and jaws are also unlike those of stoneflies. SMC

ORDER: Ephemeroptera
FAMILY: Heptageniidae
GENUS: Epeorus. 

A mayfly with two 'tails'!  This family of mayflies has distinctly flattened heads, and this particular genus has two tails and a unique gill arrangement.
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