Branch Brook

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Streams logo web.jpg Branch Brook
Stream code:PSR_SWBrnch_1652, South Wheelock Branch
Basin:Passumpsic River
State or Province:Vermont
Country:USA
Latitude:44.545111
Longitude:-72.129808
School:Lyndon Institute


The following are the most common invertebrates collected from this stream site.

Simuliidae

Simuliidae.jpg
Order
Diptera
Family
Simuliidae


Simuliidae appear rather like bowling pins with heads. Relatively speaking, we collect few members of this family and have we have not identified them past family at this point.

Click here for a close up image of the heads.




Epeorus

Epeorus.jpg
Order
Ephemeroptera
Family
Heptageniidae
Genus
Epeorus


Common name
The Quill Gordon
Tied fly
Quill Gordon
This is the only Heptageniidae genus present in this area with two tails!




Baetis

Baetis.jpg
Order
Ephemeroptera
Family
Baetidae
Genus
Baetis


Common name
The Little Olive
Tied fly
Sawyer Pheasant Tail Nymph
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.

Image of the long, dark wing pads.




Glossosomatidae

Glossosoma - Whole3.jpg
Order
Trichoptera
Family
Glossosomatidae


Common name
saddlecase caddisfly
Larvae in this family build domed cases made of small rocks, and are often wider at segment 5. The pronotum is covered in dark, sclerotized plates, but there are either no sclerites on the mesonotum, or the mesonotum is unsclerotized with the exception of a few patches. The anal proleg is broadly joined to segment 9; the anal claw has one or more accessory hooks. The pronotal excision is small (approximately 1/3 anterolaterally) to accommodate the coxae.

Commonly encountered genera include Glossosoma and Agapetus.




Hydropsychidae

Hydropsyche.jpg
Order
Trichoptera (caddisfly)
Family
Hydropsychidae


Common name
net spinning caddisfly
Tied fly
Emergent Sparkle Pupa, Vermont Hare's Ear
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.

When using the key, some features that are challenging to see are the forked trochantin and the paired sclerites in the folds between segments. Other, more easily seen key features include filamentous gills on the abdominal segments and the sclerotization of the dorsal surfaces of all three thoracic segments. Keep in mind that with smaller or more immature specimens, genus-level ID may not be possible.

Commonly found genera include Cheumatopsyche, Ceratopsyche, and Hydropsyche. Less commonly, we have found Arctopsyche and Potamyia.

Images of the forked trochantin and the paired sclerites.




Athericidae

Athericidae.jpg
Order
Diptera
Family
Athericidae


Common name
water snipe flies
Members of the family Athericidae have wrinkled bodies with prolegs on the ventral side. Their mandibles- which can be seen by carefully cutting the head open- move parallel to each other. On the end of their abdomen there are two lobes fringed with setae. Our collections include just the single genus Atherix.

Image of the two lobes of the abdomen.



Dolophilodes

Dolophilodes.jpg
Order
Trichoptera
Family
Philopotamidae
Genus
Dolophilodes


Dolophilodes stands out in the Philopotamidae family due to its slightly asymmetrical frontoclypeus on the anterior margin and its distinguishable projecting foretrochantin.

Images of the slightly asymmetrical frontoclypeus, and the projecting foretrochantin.




Drunella

Drunella Whole.jpg
Order
Ephemeroptera
Family
Ephemerellidae
Genus
Drunella


Tied fly
Bluewinged Olive Dun
The mayfly Drunella is distinguished by its large femoral “biceps;” these femora have tubercles on the leading margins. Gills are present on segments 3-7.



Leuctra

Leuctra2.jpg
Order
Plecoptera
Family
Leuctridae
Genus
Leuctra


This family of stonefly 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.

Image of the divergent wing pads.




Dicranota

Dicranota cover.jpg
Order
Diptera
Family
Tipulidae
Genus
dicranota


Dicranota can be distinguished by the two tails and their comb feet. 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.

Image of the prolegs.




Heptageniidae

Dic 2008 F Heptageniidae.jpg
Order
Ephemeroptera
Family
Heptageniidae


Common name
flatheaded mayfly
Tied fly
Light Cahill, Wingless Pale Evening Dun
This family of mayflies can be characterized by their distinctly flattened heads and striking resemblance of the character 'Jack Skellington' from the movie 'The Nightmare Before Christmas.' This family can either have two or three cerci (tails).

Commonly encountered genera include:

Epeorus

Heptagenia

Maccaffertium

Rhithrogena




Chloroperlidae

Chloroperlidae.jpg
Order
Plecoptera
Family
Chloroperlidae


Common name
The Yellow Sally
Tied fly
Yellow Sally
Stoneflies from the family Chloroperlidae have cylindrical banded abdomens. When observing their mouthparts, the glossae and paraglossae form a three-pronged (open) notch, and their hind wing pads are parallel (not divergent). Cerci have a vertical fringe of hairs pointing away from the abdomen. Setae on the pronotum are found primarily at the corners.




Optioservus

Optioservus (Larvae).jpg
Order
Coleoptera
Family
Elmidae
Genus
Optioservus


The larvae of Optioservus have open 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 sutellum observable in the dorsal view.

Images of the straight definition between segments, the dorsal ridgesand the diamond-shaped scutellum.




Blepharicera

Blepharicera.jpg
Order
Diptera
Family
Blephariceridae
Genus
Blepharicera


Common name
net-winged midges
This dipteran is characterized by six prominent "suction cups" on its ventral side and has tufts on the sides of abdominal sections.

Image of the ventral side.




Chironomidae

Chironomidae.jpg
Order
Diptera
Family
Chironomidae


Common name
Nonbiting midge
Tied fly
Griffith's Gnat
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 caddisfly family Philopotamidae.

More information on Philopotamidae.




Rhyacophila

Rhyacophila.jpg
Order
Trichoptera
Family
Rhyacophilidae
Genus
Rhyacophila


Common name
Green Caddis
Tied fly
Henryville Special or Glass Bead Caddis
In our lab, Rhyacophila is known as the "Michelin Man" due to its large banded body. It has a very obviously checker-patterned head. It also has terrifying anal claws with large accessory hooks.

Links to images that may be useful if you have a magnifying glass or microscope: Checker-patterned head. Anal claws with large accessory hooks.




Diptera

Diptera Pupae.JPG
Order
Diptera



Tied fly
Griffith's Gnat
Pupae from the order Diptera are typically found in small numbers at every site. These can be identified further, but we do not.




Hexatoma

Hexatoma.jpg
Order
Diptera
Family
Tipulidae
Genus
Hexatoma


This Tipulidae can be identified by the swollen 7th abdominal segment. The swelling is bulbous and frequently as much as 2X abdominal diameter in preserved specimens.




Cheumatopsyche

Cheumatopsyche.jpg
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.




Lepidostomatidae

Lepido.jpg
Order
Trichoptera
Family
Lepidostomatidae


Common name
The Little Plain Brown Sedge
Tied fly
Elk Hair Caddis
These have lateral humps on the first abdominal segments, but lack a dorsal hump. The dorsal of the first two thoracic segments are sclerotized. They are frequently found in four-sided cases made of square pieces of detritus.

Images of the first two thoracic segments and the four-sided cases.