Nigronia serricornis

Nigronia serricornis
Scientific classification
Kingdom:	Animalia
Clade:	Euarthropoda
Class:	Insecta
Order:	Megaloptera
Family:	Corydalidae
Genus:	Nigronia
Species:	N. serricornis
Binomial name
Nigronia serricornis (Say, 1824)

Nigronia serricornis has many common names including; hellgrammites or fishflies or saw-combed fishfies. The genus Nigronia has one other North American member N. fasciatus which lives in much of the same territory and is quite similar in all regards. They are holometabolous insects with an aquatic larval stage.N. serricornis is a common inhabitant of woodland streams in North America and they are often the largest insect predator found in 2nd and 3rd order streams. The larvae are a sit-and -wait ambush predators that feed on a large variety of invertebrates. Studies have shown that N. serricornis has a varying diet throughout the seasons.

Despite this small organism’s limited ability to disperse it has managed to spread throughout the Eastern United States. The range of N. serricornis expands northward from Florida into Ontario, and west to the US Rocky Mountains. By using genetic analyses, Heilveil and Berlocher (2006) have identified that there are six major clades of N. serricornis. The ancestral clade in the north end of their range, represent the initial colonization of N. serricornis on the Eastern US. This clade was separated from the derived clade by the Appalachian Mountains.

N. serricomis is an active predator and has a varied diet consisting of many smaller invertebrates such as midges, caddisflies, black flies, mayflies, ostracods, and small crustaceans. Studies have shown that N. serricomis changes its diet from season to season and even from month to month.N. serricomis larvae feed by foraging with their mandibles open and quickly closing them upon contact with prey.

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