BioGrubs™:
The Larval Stage of the Black Soldier
Fly
Natural History
The Black
Soldier Fly (Hermetia
illucens) has a
worldwide distribution in the tropics and warm temperate
regions. It is considered a native of the North American
continent, and can be found in many parts of the United
States. It is exceptionally active in the southeastern
states from April to November. Solider fly juveniles are
considered scavengers in nature, and help to digest and
recycle decomposing organic material including carrion,
manure, fruits, and decaying plant waste. Larvae can also
be found inhabiting beehives. Their association to humanity
is limited to compost piles, facilities producing manure,
and poorly services toilets that contain biosolids. Unlike
the common house fly or fruit fly, they are not commonly
found in association with picnics or residential buildings.
There is significant potential for use in forensic
entomology. The larvae are preyed upon by histerid beetles,
sphecid wasps, and certain varieties of birds. Common names
include: Privy Flies (associated with outhouses), Meal
Maggots (fisherman), Soldier Grubs and Phoenix Worms (trade
names).
Adult
Description
The black
soldier fly has a short lived adult stage, normally lasting
between 5-8 days. In that time period, the only really
function (besides extending the species range) is to find a
mate, and oviposit viable eggs in an appropriate food
source. This non-feeding stage is so short, the winged
adults do not even possess mouth parts, which is the
primary reason they are not associated with disease
transmission in humans. The blue-black adults range in size
from 15-20 mm, and are relatively weak fliers. Breeding of
adults occurs in flight; the females can lay up to 900 eggs
within their brief lifespan. Because it is an evolutionary
mimic, on first glance it resembles certain varieties of
mud wasp.
The tiny 1 mm
eggs hatch in a little over 100 hours, and if environmental
conditions are favorable and there is adequate food, the
cream colored larvae can reach maturity in 2-4 weeks. This
period may be extended to several months if temperature and
nourishment are less than optimal. The tough and leathery
chitin-skinned juveniles pass through 6 stages of growth
called instars. The pupae develops within the protective,
darker-colored skin of the 6th larval instar, which is
referred to as the puparium. Larvae over winter in a
sheltered dry location, with pupae development slowing
considerably during the coldest months. Depending on a
multitude of environmental triggers, pupation occurs
irregularly throughout spring and summer, so that the
emergence of adults is spread out over an extended time
period.
Creative Media
The juvenile
form of
Hermetia illucens is a robust,
hardy larvae that is yellowish in color, dry to the touch,
and surprisingly active, as the video illustrates.
High
Quality Images
