Englesby Brook

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Streams logo web.jpg Englesby Brook
Stream code:LCD_EngBrk_117
Basin:Lake Champlain Direct
State or Province:Vermont
Country:USA
Latitude:44.456134
Longitude:-73.213635
School:St. Michael's College


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

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.




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.




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.




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.




Ceratopsyche

Ceratopsyche.jpg
Order
Trichoptera
Family
Hydropsychidae
Genus
Ceratopsyche


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. Biologists have gone back and forth between lumping this genus into Hydropsyche and splitting it back out. ITIS currently lists it as a genus (Feb 2013) but we are aware of a recent paper that lumped it under Hydropsyche.




Stenelmis

Stenelmis (larvae).jpg
Order
Coleoptera
Family
Elmidae
Genus
Stenelmis


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.

Click here to see pictures of the sternum and antennae-




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.




Oligochaeta

Oligochaeta.jpg



Common name
aquatic earthworms; black worms
Aquatic earthworms lack legs and are characterized by having 20 or more segments. Unlike leeches, they lack a suction disk. We collect members of two or more orders in this class as small numbers of stream sites and they are rarely numerous. They are more common at pond and lake sites.

Image of the 20 or more segments.




Pisidiidae

Sphaerium corneum.jpg
Order
Veneroida
Family
Pisidiidae


Fingernail clams are the most common small clams that we find in Vermont rivers. Larger bivalves should not be sampled because they may belong to a protected species. Under no circumstances should clams be moved from one river site to another.




Asellidae

Isopodaasellidae2.jpg
Order
Isopoda
Family
Asellidae


Common name
sow bugs
These aquatic sow-bugs have seven pairs of legs and a dorso-ventrally flattened body. They have two pairs of antennae; one pair is much longer than the other pair.

Images of the body and the two pairs of antennae.



Tipulidae

Tipula cover.jpg
Order
Diptera
Family
Tipulidae


Common name
The Crane Fly
Tied fly
Gangle Legs
Like other larvae from the order Diptera, members of the family Tipulidae (crane flies) lack legs. Tipulidae have retracted, difficult-to-see head capsules at one end, and a spiracular disk at the other end. The spiracular disk can sometimes look like a face leading to some confusion about which end is which. Upon gently cutting the head open, one can see that the mandibles are not parallel to each other, but rather move against each other.

The genera we've encountered include Antocha, Dicranota, Hexatoma, Limnophila, Molophilus, Pedecia and Tipula.