ENTOMOLOGY
DATE: O2-07-08
MD. Asaduzzaman
Lecturer
Department of Entomology
COURSE TITTLE: Basic entomology.
COURSE CODE: ENT-211
ENTOMOLOGY:
Entomology comes from two Greek words. ENTOM-Insect, LOGOS-Knowledge.
Knowledge about insect.
DEFINITION:
Entomology is the scientific study of insects and their relatives (mite)
OR
Entomology is the branch of science (zoology) which deals with insect’s habit, habitat morphology, physiology, biology, nature of damage, appropriate control measures etc.
INSECT:
Insect is an invertebrate animal under the class insecta / hexapoda which bears three pairs of thoracic legs.
Insecta-segmented body.
Hexa-6
Poda-legs.
BODY:
Body divided into three regions.
(1) Head.
(2) Thorax.
(3) Abdomen.
MITE:
Mite is an microscopic living organism which bears 4 pairs of legs and body divided into two regions –Chephalothorax and abdomen.
Head +thorax-cephalothorax.
DEFFERENCE BETWEEN INSECT AND MITE:
INSECT MITE
(1)Insect’s has three pairs of legs (1) Mites has 4 pairs of legs.
(2)Body divided into three regions: (2) Body divided into two regions:
Head, Thorax, and Abdomen. Cephalothorax and abdomen.
(3)Not microscopic. (3)Microscopic.
(4)Insect under the class insecta. (4)Mite under the class arachida.
(5) e.g. Cockroach,
WHY WE READ ENT?
IMPORTANCE OF ENT.
(1) Production of HRT and AGR.
(2) Protection of PLP and ENT.
(3) Generating of GPD and Biotechnology,
BENIFICIAL SIDE:
(1) 9
(2) Pollination, Monocots, Dioeciously.
(3) Used as food for 500 species.
(a) Egg, Honeypot ant
(b) Bogong muth.
(c) Grasshopper.
(d) Cricket.
Used as fish food.
(4) It improve the physical condition of soil.
(5) Insect used as decomposition.
(6) Used as medicinal purpose.
(7) Used as beautification.
(8) Insect used as scientific researches.
(9) Drosophila insect used as researches.
HURMFUL SIDE:
(1) In
(2) Factor of virus.
(3) Valuable product (book, cloth, wooden furniture) are damage by insect.
(4) Man and domestic animal (directly) (Morse fly, mosquito, bed bug).
(5) Sting ((bee, ant).
(6) Bad order (rice burg).
(7) Blister (rice burg).
Date: 05-07-08.
Lecture-02.
CHARACTERS AND CLASSIFICATION OF INSECTA
CHARACTERS OF INSECTA
(1) Body divided into three regions: Head, Thorax, Abdomen.
(2) The interior port ion is the head consist of 6 fused segment with a pairs of compound eye, a pair of antenna, and a mouth parts.
(3) The second region is the thorax consist of 3 free segments, each segment bears a three pair of leg and last two segment bear two pair of wings.
(4) The posterior portion is the abdomen consists of 11 segments. The 8th, 9th, and 10th segments bear appendages usually modified for mating or egg laying purposes.
(5) Respiration is occurred by trachea, integument gills etc.
(6) Excretion is done by malpighial tubules.
(7) Sexes are separate.
(8) Development is direct often more complicated by metamorphosis.
CLASSIFICATION:
RECHARD AND DEVIS-29 order.
Biology of insect : S.C. Saxena.
CLASS – Insecta.
SUB CLASS – (1) Apterygota. Wingless insect.
(2) Ptenygota. Winged insect.
A=no pteron=wing.
APTENYGOTA:
(a) Wingless insect.
(b) Metamorphosis slight or absent.
(c) Adults with one or more preginital abdominal appendages.
(d) Adult mandible articulate with head.
ORDER:
(1) Thysanuna e.g. Silver fish.
(2) Diplura e.g. Japygids.
(3) Protura e.g.Protaturans.
(4) Collembolan e.g. Springtails.
PTENYGOTA:
(1) Winged insect.
(2) Metamorphosis incomplete or complete.
(3) Adult without pregenital abdominal appendages.
(4) Adult mandibles- Articulate with the head at two points.
DIVISSIONS: 02
(1) Exopterygota. (2) Endopterygota.
| Exopterygota endopterygota (1) Wings develop externally. (1) Wings develop internally. (2) Metamorphosis incomplete. (2) Metamorphosis complete. (3) Immature stages are nymph (3) Yong stage are called harvae Which is resemble to adult with defferent from adult`s In structure and habit. In structure and habit. (4) Pupal instar absent. (4) Pupal instar present. (5) Exopterygota has 16 orders. (5)Endopterygota has 9 orders. |
| ORDER OF EXOPTERYGOTA (1) Ephemeroptera e.g. May flies. (2) Odonata e.g. Dragon fly. (3) Plecoptera e.g. Stone flies. (4) Grylloblatodea e.g. Grylloblatodea. (5) Orthoptera e.g. Grasshopper. (6) Phasmida e.g. Stick insect. (7) Dermaptera e.g. Erswigs. (8) Embioptera e.g. Embiids. (9) Dicyoptera e.g. cockroach. (10) Isoptera e.g. Termites. (11) Zoraptera e.g. zorapterans. (12) Psocoptera e.g. Book lice. (13) Mallophaga e.g. Bird lice. (14) Anoplura e.g. Head lice (15) Hemiptera e.g. All bugs. (16) Thysanoptera e.g. Thrips. | OREDR OF ENDOPTERA (1) Neuroptera e.g. Lace wing. (2) Mecoptera e.g. Scorpion flies. (3) Lepidoptera e.g. Butterfly and moth. (4) Trichoptera e.g. Caddish fly. (5) Diptera e.g. Flies and masquitues. (6) Siphonaptena e.g. fleas. (7) Hymenoptera e.g. Ants, Bees. (8) Coloeptena e.g. Beetles and Weevils. (9) Strepsiptera e.g. Stylopids. |
CHARACTERS AND CLASSIFICATION OF ARACHRIDA AND CRUSTACEA
CHARACTERISTICS OF ARACHRIDA:
(1) They are mostly terrestrial but few are aquatic.
(2) Body divided into prosoma (cphaiothorax), mesoma (abdomen) and metasoma (tail)
(3) They have four pair of legs.
(4) Antennae absent.
(5) Excretion is done by malpighian tubules.
E.g. Spider, Mite,Tics.
CLASSIFICATION:
(1) Scorpionida e.g. Scorpions
(2) Pseudoscorpionida. e.g.Pseudoscorpions.
(3) Philangida e.g. Haarvestmen.
(4) Acarilna e.g. Mites.
(5) Thelyphonida e.g. whip scorpion.
(6) Schizomida e.g. Shorttclledwhip scorpion.
(7) Amblypygida e.g. Tailless whip scorpion.
(8) Palpignada e.g. Micro tailed whip scorpion.
(9) Ricinuleida e.g. ricinuleids.
(10) Solpugida e.g. Sun scorpion.
(11) Araneida e.g. Spider.
CHARACTERISTIC OF CRUSTACEA:
(1) They are aquatic.
(2) Body divided into two regions: Cephaiothorax and Abdomen.
(3) Cephalotharax is covered by a hard structure called carapage. E.g. Shrimp.
(4) They have 5 pairs of legs.
(5) They have two pair of antenna and usually biramous.
(6) Genital opening present at the 5th pair of legs.
E.g. Shrimp, lobe star.
ORDER:
(1) Isopoda e.g. water scud.
(2) Decapoda e.g. Sow bugs.
(3) Stomatopoda e.g. Stomatopods.
(4) Amphipoda e.g. Shrimps.
DATE:
Lecture-3
GENERAL ORGANISATION OF AN INSECT:
Insect body divided into three distinct regions:
HEAD:
Head consist of a pair of compound eye, pair of antenna and a mouth parts.
THORAX:
Thorax consists of three segments: Prothorax, Mesothorax, Metathorax.
Each thoracic segment bears one pair of legs and last two segments bear two pair of wings.
NOTUM:
DORSAL SURFACE OF THE THORAX IS CALLED NOTUM.
STERNUM:
Ventral surface of the thorax is called sternum.
PRONOTUM:
Dorsal surface of the thorax is called pronotum.
MESONOTUM:
Dorsal surface of the mesothorax is called mesonotum.
METANOTUM:
Dorsal surface of the metathorax is calledmetanotum.
Prothorax is always wingless.
PLENON:
Lateral side of the insect body.
ABDOMEN:
TERGUM:
Dorsal surface of the abdomen is called tergum.
STENUM:
Ventral surface of the abdomen Is called sternum.
SPIRACLE:
External opening of the tracheal system.
No, of spiracle in a typical insect -8 pairs.
OVIPOSITOR:
It is a egg laying organ.
Cr= Cercus (cercil-pl): Last pair of abdominal appendages is called cerci.
EPT= epiproct : A small dorsal plate above the anus is called epitroct.
PPT (Paraproct): A small ventral plate below the anus.
Date :19-07-08
Lecture :04
ANTENA
DEFINITION:
Insect antennae are a pair of movoble, highly senitive, segmented appendeges =wings which arise from infront of the head in between two eyes or the base of the mandibles. Insect antenna are of series of segments and sensory in function.
CHARACTERS:
-Mvable
-Highly sensitive
-Segmented
-Variable in size
-Sensory in function
FUNCTION:
(1) To feel their way.
(2) To detect danger.
(3) To locate their food
(4) Find their mates
(5) Communicate with other of their won
STRUCTURE:
An insect antenna consist of three parts:
(1) Scape
(2) Pedical
(3) Flagellum
SCAPE:
It is the first segments of the insect antenna, comperatively larger in size. It come it`s with the head.
PADICEL:
It is the second segment of a antenna, smoll in size. A sense organ present here called Jhonston`sorgan
FLAGELLUM:
It is the 3rd part of the insect antenna. It composed of series of sub- segments.
TYPE OF ANTENNA :
There are many types of antenna.
(1) Filiform e.g. Grasshopper.
(2) Moniliform e.g. Termites.
(3) Serrate e.g.Click beetle.
(4) Capitate e.g. Scavanger.
(5) Clavate e.g.Butterfly.
(6) Aristate e.g. Housefly.
(7) Stylate e.g. Horse fly.
(8) Plumuse e.g Male mosquito.
(9) Plilose e.g. Female mosquito.
(10) Pectinate e.g. Moths
(11) Bypectinate e.g. Moths.
(12)Geniculate e.g. Honet bee.
(13)Setaceous e.g. Dragon fly. (14)Lemellate e.g. Scrabid beetle, Dung beetle.
(15)Flabellate e.g. Cedar beetle.
FILIFORM:
(1) Thread like antenna.
(2) All segment are about same thickness.
(3) Having no constriction between two segments.
MONILIFORM:
(1) Bead like antenna.
(2) Segment are globular type .
(3) Having prominent contriction between two segment.
SERRATE:
(1) Saw like antenna .
(2) There are triangular projection in each segments.
CAPITATE:
(1) Having a cap at the tip.
(2) All the segments are abroughly enlarged.
CLAVATE :
(1) Segment are gradually enlarged.
(2) Last segment is club shaped.
ARISTATE:
(1) Segments are gradually enlareged.
(2)Last segments bears a conspicuous arista.
(3)Arista may be hairy or naked.
STYLATE:
(1) Last segment are modified into style or finger like structure.
PLUMOSE:
(1) Segments are feathry.
(2) Hairs are densely arranged.
PILOSE:
(1) Segment are comperatively larger than plumose.
(2) Hairs are not densely arranged.
PECTINATE:
(1) Comb like structure present at the one side of the antenna.
(2) All the segments are lateraily narrow.
BYPECTINATE:
(1) Comb like structure present at the both side of the antenna.
(2) Aii the segments are laterally narrow.
GENECULATE:
(1) Scape is long and another segment are smoll which make a angle with the first segment.
(2) Emblow shaped antenna.
SETACEOUS:
(1) Seta like antenna.
(2) Last segment is tapering to the end.
LEMELLATE:
Terminal segment are expanded laterally to form a leaf like structure.
FLABELLATE:
TERMINAL SEGMENT ARE EXPANDED LATERALLY TO FORM A TAR QUE LIKE STRUCTURE.
WING
DEFINITION OF WING :
Wing is a expension of the body wall and it contains the same elements of the wall namely cuticulin, epidermis, basement membrane and the lumen contain nervous, thrachea and blood. Insect wing is a membranous appendages originated from mesothrax and metothorax. The prothrax is always winglss.
FUNCTION:
(1) Helps in flying .
(2) To flee away quicckly from enemies and danger.
(3) Helps in mating.
(4) Helps to make their nest.
(5) To protect body wall.
STRUCTURE 0F A TYPICAL WING:
It consist two type of vein.
(1) Longitudinal vein.
(2) Cross vein.
LONGITUDINAL VEIN :
It consist with the following parts.
(1) Costa(C).
(2) Sub costa(Sc)
(3) Radius(R).
(4) Radius sector(Rs)
(5) Mediam (M)
(6) Cubitus(Cu)
(7) Anal vein(A)
COSTA:
IT IS THE OUTER MARGIN OF THE INSECT WING.IT IS UNBRANCHED.
SUB-COSTA:
It remain just bellow the costa. It is devided into short branches(Sc1 and Sc2)
RADIUS:
It remain bellow the sub-costa. It is divided intotwo main branches(R1 and Rs)
RADIUS SECTOR:
It is divided into four branches(R1, R2, R3, R and R4)
Median:
Median divided into four short branches(M1, M2, M3 and m4)
Cubitus:
It is divided into two short branches (Cu1 and Cu2). Cu1 again divided into 2 branches{Cu1(a) and Cu1(b)}.
Anal vein:
It is unbranched. The number anal vein is 3- First anal, Second anal and Third anal.
CROSS VEIN:
The number cross vein is 7.
NAME OF THE VEIN VEIN CONNECTED ABBREVIATION
WINGS MODIFICATION:
It is 5 types
1.Tegmina
2. Hemelytra
3. Elytra
4. Haltera
5. Hooklet
TEGMINA:
Fore weings are modified into harden, leathery consistancy. The harden structure is called tegmina, Hind pairs of wings are normal membraneous. eg. Insect under the order Orthoptera, Dermaptera and Dyctyoptera.