Fruit flies part 1: Introduction to Drosophila

Fruit flies are an excellent food for many surface feeding killifish, closely resembling their natural diets in the wild. They are easy to culture, quickly, cheaply and in large numbers. Fruit flys are rarely available in pet shops, but are widely available online, and very much worth trying, even if you don't bother culturing them on an ongoing basis.

What is a fruit fly?

Fruit flies are small flies that live on and around decaying fruit and vegetation. They occur worldwide, except the very coldest regions. The species most familiar to scientists, aquarists and herpetologists are in the genus Drosophila which literally means 'dew-lover' in Greek. Also known as 'bar fly' or 'vinegar fly', these little flies are commonly found around waste bins, bars, orchards etc, and they are widely used in laboratories as research animals. The species we feed to our fish however, have been bred to have shorter 'vestigial' wings, and as such can not fly. These are typically from two species Drosophila melanogaster and Drosophila Hydei.

Why fruit flies?

Although dealing with highly mobile flies can be trickier than with worms, there are some great reasons to consider culturing them.

• Nutritious - all fish can be trained to eat flies, but surface feeders love them. Not only are they relished by the fish, but they also have a high fibre content, and are therefore a great contrast to the fattier foods such as worms and beef heart. They are also typically disease-free, unlike some aquatic livefoods.
• Prolific An adult fly can lay 20+ eggs in a day. Once you get the hang of it, fruit flies are easy to maintain, and at 25 deg. centigrade the development of Drosophila melanogaster takes just 9 days.
• Availability - unlike collected livefoods, cultured Drosophila are available all year round.
• Flightless flies available - fruit flies have been studied in laboratories for very many years, and a lot is known about the humble fruit fly. Over the course of these studies, geneticists line-bred many strains of fly, including vestigial-winged, and even wingless flies. These are the flies typically cultured by hobbiests.

Drosophila larvae in a typical culture

Drosophila larvae climb up the walls of their vials and chrysalise

Drosophila pupae

Drosophila life cycle

Adult flies lay a lot of eggs. A single female can lay over 20 eggs in a day, and can store sperm within her body for up to two weeks, to lay fertilized eggs at will.

Eggs take 23 hours to hatch at 25 deg C. Once they do hatch, the larvae bury into the media and grow. They will stay as larvae for five days, in which time they undergo three moults.

Eventually they will start to climb the sides of the vial, and when fully grown will settle near the top, and form a chrysalis. The change from maggot to fly takes around three days, but again, is temperature dependent.

The image to the right shows a newly formed chrysalis with the lava's segments still visible (1), an older chrysalis with the fly clearly visible. The red dots are its eyes (2) and an empty chrysalis from which a fly will have hatched (3).

Once the flies have emerged they must be moved to new vials, as there is now no food suitable for them in the old vials.

Fruit fly cultures for sale

Fruit Fly & Drain Fly Killer - Simple Commercial Drain Gel Treatment

Saint Louis, Missouri, 631**, UNITED STATES OF AMERICA

$27

Fruit Fly & Drain Fly Killer - Simple Commercial Drain Gel Treatment ?? Eliminates Gross Fruit Flies, Drain Flies, Sewer Flies & Gnat Infestations From Any Drain. Fast & Easy
FAST ACTING & EASY TO USE ?? Simply Pour This Specially Formulated Gel Solution Down Any Sink Drain Or Floor Drain Where Fruit Flies and Drain Flies Breed. Works On The Worst Fruit Fly & Drain Fly Infestations. Can Be Used In Bars, Bathrooms, Homes, Hotels, Kitchens & Restaurants
HOW IT WORKS ... more

Flightless Fruit Fly Culture Hocks Herps - Melanogaster (Producing)

Manchester, Pennsylvania, 173**, UNITED STATES OF AMERICA

$22

Drosophila melanogaster (also known as melanogaster) are likely the most common fruit fly and measure about 1 / 16 of an inch.
For best results store at 75-78°F and 60-80% humidity
This producing culture will be ready to feed from in 3-5 days after arrival.
Live arrive is guaranteed when you select Heat / Cold pack.... more

32oz Flightless Fruit Fly Culture

Wichita, Kansas, 672**, UNITED STATES OF AMERICA

$12

32oz Flightless Fruit Fly Culture.
... more

NEKTON Drosophila Breeding Concentrate 1000g Fruit Fly Culture Food Germany

South Gate, California, 902**, UNITED STATES OF AMERICA

$40

Condition:
New

Item Specifics:

* Brand: NEKTON
* Model: Drosophila Breeding Concentrate
* Type: Fruit Fly Culture Food
* Weight: 1000g (35 27 oz)
* Country / Region of Manufacture: Germany
* Intended For: Drosophila (Fruit Fly) Cultures
* Suitable For: Reptile, Amphibian, and Insect Feed Breeding
* MDD: 2028-01-18

Description:
New sealed container of NEKTON-Drosophila breeding concentrate. Complete feed concentrate designed for breeding... more

Terrarium Vent ( Fruit Flies Proof) Set Of 4

Pembroke, North Carolina, 283**, UNITED STATES OF AMERICA

$15

Set of 4 Secure Terrarium Vents - Escape-Proof for Flightless Fruit Flies
Product Overview
Upgrade your terrarium setup with these premium, custom-fit ventilation covers. Designed specifically for hobbyists, these vents allow for essential airflow while providing a 100% secure barrier against even the smallest feeder insects, such as flightless fruit flies (Drosophila)
Whether you are keeping dart frogs, mantids, or other sensitive species, our vents ensure your enclosure remains ... more