- The document discusses different types of insect mouthparts including mandibulate, chewing-lapping, sponging, piercing and sucking, and siphoning. - Mandibulate mouthparts typically consist of an upper lip, hypopharynx, pair of mandibles, pair of maxillae, and lower lip. They are adapted for biting and chewing. - Chewing-lapping mouthparts found in bees and wasps have mandibles and labrum for chewing and maxillae modified to form a lapping tongue for liquid food. - Sponging mouthparts have a retractable proboscis under the head for sipping or liquefying liquid food. Flies have

1. PRESENTATION TOPIC- TYPES OF MOUTH PARTS
Submitted to- Submitted by-
Department of zoology Naman Songara
DEPARTMENT OF ZOOLOGY
M.Sc. Final year

2. Typical mandibulate mouthparts
• The mandibulate mouthparts are the primitive form. They typically consist of an
• anterior upper lip or labrum,
• the hypopharynx,
• a pair of mandibles,
• a pair of maxillae
• a posterior lower lip or labium.
• The mandibles, maxillae and labium represent modification of typical paired
appendages of three primitive segments
• They are known as biting and chewing type.

4. Labrum.
• Typically, this is a movable flap hanging down
from the edge of the clypeus and covering the
mouth.
• Its inner side forms the front of the pre-oral
cavity and is called the epipharynx

5. Hypopharynx
• It is an unsegmented outgrowth of the body wall
• lies in the preoral cavity like a tongue.
• The portion of the preoral cavity between the hypopharynx and
labrum is the cibarium.
• The portion of the preoral cavity between the hypopharynx and
labium forms the salivarium.
• Salivary duct opens through it.

6. Mandibles
• They are the paired appendages of fourth head segment behind the
mouth and are highly sclerotised unsegmented jaws.
• Each mandible forms two articulations with the cranium.
• Each mandible has a proximal molar or grinding and a distal incisor or
cutting regions.

7. Maxillae
• They lie directly behind the mandibles and
are the paired appendages of fifth head
segment and serve as accessory jaws,
• helping in holding and chewing food.
• Each maxilla is composed of the following
parts
• Cardo
• Stipes
• Galea.
• Lacinia
• Palpus.

8. Labium
• Lower lip, bounds the mouth cavity from
below or behind from base of preoral cavity
• 3 median sclerite, submentum (large basal),
Mentum (middle), Prementum (apical)
• On the lateral side of prementum 2 small
sclerite Palpiger bearing 3 segmented labial
palpi.
• Distally prementum bears 2 pairs of lobes.
• Outer pairs of lobes are called paraglossae and
inner pair of lobes are called glossae. both
pairs when fused are called ligula

9. Modification
A. Chewing-lapping type (honeybee
wasp)
• Such type of mouthparts are also
adapted for taking liquid food
• The mandibles and labrum are of
the chewing type and are used for
grasping prey (as in wasps) or
molding wax (as in worker bees).
• Maxillolabial str. are modified to
form lapping tongue
• Glossa terminates into circular
spoon like str. Called flabellum
used to lick the nectar

10. Sponging type
• The mouthparts comprise a fleshy and
retractile proboscis which lies under the head .
• Is formed by three components, the basal
rostrum, middle haustellum and the distal pair
of labellum.
• The mandibles are absent, and maxillae are
represented by its palpi
• The flies sip the liquid food , or it may first be
liquefied by salivary secretions of the fly
• e.g., house flies

11. Piercing and sucking type
a) Dipterous type (Mosquito type)
• In female mosquitoes, in which paired mandibles, paired
maxillae, labrum-epipharynx and hypopharynx, all six parts are
modified to needle-like stylets .
• Needle-like mandibles lie on each side of the labium-epipharynx,
the distal end being serrated for pricking the host skin.
• In male mandibles and maxillae are reduced and they feed the
nectar and juices of decaying fruits
b) Hemipterous type (Bug type)
• Labium projects downwards from the head like a beak
or proboscis
• Mandible and maxillae are modified to form stylets
• Mandibular stylets possess blade like tips while
maxillary stylets possess saw like tips
• Epipharynx and hypo pharynx are absent.

12. Siphoning type
• This type of mouthparts are found in butterflies and moth.
• The long-coiled proboscis is formed by the two galeae of
the maxillae; the food channel is between the galeae.
• The labrum is reduced to a narrow transverse band across
the lower margin of the face, and the mandibles and
hypopharynx are lacking.
• The maxillary palpi are usually reduced or absent, but the
labial palpi are usually well developed.
• There is no special salivary channel.
• The liquid food is sucked or siphoned up through the
proboscis
• When used, the proboscis is uncoiled by blood pressure; it
recoils by its own elasticity

13. Reference
• ELEMENTS OF ENTOMOLOGY BY DR. RAJENDRA SINGH
• bugs.bio.usyd.edu.au
• Structure and function of insect mouthparts

14. Thank you