COMMON INSECTS - Cockroaches

Description

Adults are up to 53mm long, reddish brown except for a pale brown to yellowish band around edge of head shield. Both male and female have wings and are moderately good fliers.

Biology

On average the capsule contains 14 – 16 eggs. Development time can be anywhere from 5 to 26 months. They live about 14 months.

Habit

American cockroaches are found in residences, commercial buildings and drainage & sewer systems. They have a likeness for fermenting foods. During summer months they are found outdoors.

Description

Adult Oriental cockroaches are about 32mm in length. Both male and female adults are very dark brown, nearly black with a greasy sheen. They have thick bodies with very short wing covers on top. They can not fly.

Biology

The egg case brown, and purse shaped and contains 16 eggs. Immature cockroaches emerge in 6 to 8 weeks and require 6 to 12 months to mature. Adult cockroaches can live up to one year.

Habit

They enter houses via sewer connections, under doors, around utility pipes, air ducts, or other openings in the foundation. They are found with decaying organic matter indoors and out. Indoors, Oriental cockroaches prefer dark, moist areas.

Description

The Australian cockroach is now a common species in Hong Kong. Adults are of 32–35 mm in length, and range in colour from reddish-brown to dark-brown and have completely developed and functional wings. They look similar to the American cockroach but have a yellow band along the outer of both wings starting from near to the wing joint.

Biology

The egg capsule contains up to 24 embryos within the egg capsule (almost twice as many as the American cockroach). The egg case will hatch in approximately 40 days. Development time to adult can take 6 – 12 months. Lifespan after development can be 4 – 6 months. An adult female can produce 20 – 30 egg cases in her lifetime.

Habit

Australian cockroaches prefer warmer climates. They thrive in moist conditions, but also can tolerate dry conditions if water is not available. It often lives around the perimeter of buildings and prefers eating plants but can feed on a wide array of organic (including decaying) matter. Indoor the Australian cockroach can be found in areas where there are water pipes, sinks, toilets, cupboards and other environments with dark and warm conditions .

Description

The Brown-banded cockroach is 10 – 14mm in length, tan to light brown in colour, with 2 light, irregular bands across their wings. It can be confused with the German cockroach.

Biology

The egg capsules contain between 14 to 18 eggs and the female attaches it to a protected surface. The egg case will hatch in approximately 30 days. Development time to adult can be between 2 to 7 months. Adults have an average lifespan of 10 months.

Habit

Brown-banded cockroaches prefer to stay hidden high on walls, behind picture frames, inside cracks and crevices, in furniture and light switches and underneath or alongside household appliances. They can be found throughout the home.

Description

Adults are about 12mm in length. They are light brown to tan except for 2 dark longitudinal stripes on the head shield. Females are darker than males. They rarely fly.

Biology

The egg capsule is yellowish brown but usually two-toned. Each capsule holds about 30 – 40 eggs. The female carries her egg capsule until it is within 1 – 2 days of hatching. Developmental time usually varies from 54 – 215 days. The adults will live about 100 – 200 days.

Habit

German cockroaches prefer warm and humid areas. They are found in kitchens, restaurants and bathrooms. Infestations often occur in rooms where people eat and drink. They feed on almost anything of nutrition value including such things as soap and glue.