Silverfish are small, wingless insects that feed on starches and sugars. They have long antennae and move in a wiggling motion. Silverfish lay eggs in cracks and crevices, and go through many molts during their multi-year lifecycles. Though primarily nocturnal and found worldwide in damp areas, some domestic species can damage household goods by feeding on materials like paper and cloth. Integrated pest management of silverfish involves both physical controls like dehumidification and vacuuming, as well as borate-based chemical treatments.

1. ORDER THYSANURA
(SILVER FISH)
Presented To: Dr. Shahzad Ali
Presented By: Mujahid Hussain
2019-mphil-1385

2. Silver Fish (Lepisma saccharina)
■ The name Thysanura, derived from the Greek "thysano-" meaning
fringed and "ura" meaning tail, refers to the long, fringed filaments
on the abdomen of silverfish.
■ A silverfish (Lepisma saccharina) is a small, wingless insect in
the order Zygentoma (formerly Thysanura).
■ Its common name derives from the animal's silvery light grey colour,
combined with the fish-like appearance of its movements.
■ However, the scientific name (L. saccharina) indicates the silverfish's
diet consists of carbohydrates such as sugar or starches.

3. Description
■ Silverfish are nocturnal insects typically 13–25 mm (0.5–1.0 in) long.
■ Their abdomens taper at the end, giving them a fish-like appearance.
■ The newly hatched are whitish, but develop a greyish hue and metallic
shine as they get older.
■ They have two long cerci and one terminal filament at the tip of
the abdomen between the cerci.
■ They also have two small compound eyes.
■ They have long antennae, and move in a wiggling motion.
■ Silverfish typically live for two to eight years.
■ They are largely oviparous, depositing their eggs in cracks and crevices out
of sight.
■ They may be six or more instars, and in tropics maturity is reached in less
than a year while in temperate regions two or more years are required to
complete a generation.

4. Scientific Classification
■ Kingdom: Animalia
■ Phylum: Arthropoda
■ Sub-phylum: Hexapoda
■ Class: Insecta
■ Sub-class: Apterygota
■ Order: Zygentoma
■ Family: Lepismatidae
■ Genus: Lepisma
■ Species: L. saccharina

5. Order Thysanura
(Thysanurans, Bristletails, Silver Fish Moths, Slickers)
Diagnostic Features
 Small, primitive, elongated,
flattened, naked or scaly bodies.
 Biting mouth-parts, maxillae long.
 Antennae long and many-
segmented.
 Compound eyes well developed,
vestigial or absent.
 Ocelli present or absent.
 Legs: Coxae small, tarsi 3 or 4
segmented with two or three claws.

6. Habit & Habitat
■ Almost world-wide in distribution. They are among the most primitive
of insects.
■ Usually white, grey, brown or otherwise pigmented to harmonize with
their immediate surroundings in the ground.
■ They are apterous in nature and entirely dependent upon crawling,
running and jumping.
■ The habitat of these insects are of quite variable in nature.
■ Majority of species adapt damp places under leaves, debris, bark, in
rotten wood, mosses, lichens, on stones, trunks of trees and nests of
ants and termite.

7. Cont…….
■ They are both diurnal and nocturnal and
usually omnivorous in their feeding
habits.
■ Most of them are vegetarians that eat
dry and decaying vegetation, fungi,
lichens, mosses and similar plant
material.
■ House-inhabiting forms feed on cereals,
pastes, glues, paper as well as starched
clothing and sized silk and rayons.
■ They may rarely eat woolen goods and
other animal products.

8. Morphology
■ The body seems to be naked but in fact they are usually somewhat
hairy or covered with overlapping metallic scales and look like
miniature dragons.
■ Head is wide and not condtricted behind, antennae 30 or more
segmented, compound eyes large and prominent or vestigial or
absent, ocelli are present in few forms.
■ Mouth parts: mandibles slender, entire or in two parts, incisors and
molar areas wide apart, maxillary palpi composed of 4 to 7
segments, labial palpi 3 segmented.

9. Cont…….
■ The thorax forms the widest region, legs similar, often with one or
more movable styli and hind coxae, tarsi 3 or 4 segmented with
paired claws.
■ Abdomen composed of 10 complete segments and the 11th segment
often modified into median caudal filament. The cerci often of 50 or
more segments arise from the 10th segment.

10. Reproduction
■ Before silverfish reproduce, they carry out a ritual involving three
phases, which may last over half an hour.
■ In the first phase, the male and female stand face to face, their
quivering antennae touching, then repeatedly back off and return to
this position.
■ In the second phase, the male runs away and the female chases him.
■ In the third phase, the male and female stand side by side and head
to tail, with the male vibrating his tail against the female.
■ Finally, the male lays a spermatophore, a sperm capsule covered
in gossamer, which the female takes into her body via
her ovipositor to fertilize her eggs.

11. Cont……
■ The female lays groups of fewer than 60 eggs at once, deposited in
small crevices. The eggs are oval-shaped, whitish, about 0.8 mm
(0.031 in) long, and take between two weeks and two months to
hatch.
■ A silverfish usually lays fewer than 100 eggs in her lifetime.
■ When the nymphs hatch, they are whitish in colour, and look like
smaller adults.
■ They may go through 17 to 66 moults in their lifetimes, sometimes
30 in a single year—many more than most insects.

12. Life Cycle

13. Economic Importance
■ Domestic species such as silverfish and firebrats may cause
extensive damage to household goods.
■ They often feed on wallpaper paste, bookbindings, and the starch
sizing of some textiles.
■ Cardboard and other paper products may also be damaged.

14. IPM for Order Thysanura
■ There are two methods for the control of silverfish.
1. Physical Control
2. Chemical Control

15. 1. Physical Control
■ Dehumifying
■ Vaccuming
■ Removal of food
■ Trapping
■ Eliminating harborage sites
■ Drying store articles

16. 2. Chemical Control
■ Diatomaceous earth
■ Borate-based insecticidal dust production
■ Silica aerogel
■ Residual insecticides