The following points highlight the thirteen key excretory organs discovered in arthropods. The excretory organs are: 1. Nephridia 2. Coxal Glands 3. Environment-friendly Gland 4. Covering Glands 5. Malpighian Tubules 6. Hepatopancreas 7. Fat body 8. Exoskeleton 9. Intestinal Caeca 10. Midgut Epithelium 11. Pericardial cells 12. Nephrocytes 13. Oenocytes.

Excretory body organ # 1. Nephridia:

These are existing in the Peripatus and also are located on the lateral side of the segmented body cavity. Number of this paired organs correspond to the number of the segment of the trunk.

Each nephridium is composed of a terminal vesicle which opens to the exterior through one end and remains linked to a coiled loop through the other. This loop is known as nephridial canal and it opens inside the human body cavity. Its interior lining is ciliated.

Excretory organ # 2. Coxal Glands:

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These glands are current only in Arachnida and their structures and positions differ (see Table 18.18—Arthropoda). Every coxal gland is composed of convoluted tu­bules, called labyrinth and a sac referred to as laby­rinth sac. It opens externally by a short tube.



Excretory organ # 3. Environment-friendly Gland:

It is also known together the antennal gland or maxillary gland. In part species, the offal are also called environment-friendly gland or antennal gland due to the fact that of their colour and also location (e.g., Astacus). In part freshwater crustacean species, the organs space situated near the maxillary segments and are called maxillary glands.


It is discovered in Malacostraca (excepting Isopods) and larval creates of all Crustaceans, especially in Entomostracan larvae. The is current in the proximal segment the the second antenna or adjoining areas of the head. Each gland has three parts—end sac, labyrinth and bladder. The labyrinth is the appropriate excretory gland.

Excretory organ # 4. Shell Glands:

These glands are likewise known together maxillary glands and also are present in the coxopodites of 2nd maxillae in Branchiopoda, Ostracoda, Copepoda, Cirripedia and also larval develops of every Crusta­ceans.

Excretory body organ # 5. Malpighian Tubules:


These are lengthy filamentous bodies with or without lumen and also are consisted of of ciliated or cubical epithe­lium. These tubules normally originate from the an ar of the gut which denotes the start of hindgut. Amongst the Crusta­ceans, the Amphipods own one pair of tubules i beg your pardon originate together diverticula the the alimentary canal.

In Insecta these construct from the undifferentiated an ar between the midgut and also hindgut and also the number different from 2 to 150. Malpighian tubules take place in all insects except in Collembola, few of the Thysanura and the Aphids. The tubules regularly occur in two’s or multiples of two.

The Malpighian tubules may be di­vided into 4 main types:

(a) In the simplest type the tubules join at the junction that mid­gut and hindgut. The distal end of the tubules remain free and end blindly. The components of the tubules are usually fluid and also sometimes discovered the crystals as soon as the insects are discovered in arid condition, e.g., Orthoptera, Dermoptera and Coleoptera.

(b) In the second kind the distal end of the tubules are attached to the hindgut. The problem of these is well-known as cryptonephridial or cryptonephridic or Cryptosolenic. This condition is seen amongst many Coleoptera and most Lepidoptera. Cryptonephridial condition is checked out in the insects as soon as they live in the drier environ­ments and also that help the insects to conserve water by absorbing it indigenous the faeces.

(c) The Malpighian tubules that the third kind remain complimentary at the distal ends and also connect proximally v the gut v ampullae, and also are discovered in Hemiptera.


(d) The fourth type of Malpighian tubules are uncovered in the Lepi­doptera and also this form is a combination of second and 3rd types. Two to four pairs of tubules are discovered in Myriapods and Arach­nids and in the later on the tubules space endodermal in origin.

Excretory body organ # 6. Hepatopancreas:

In Limulus, absorp­tive cell are present in the hepatopancreas. These cells shed huge amount the calcium phosphate as excretory product right into the in­testine with which that is eliminated in addition to faeces.

Excretory body organ # 7. Fat Body:

In Insecta, Myriapoda and Onychophora, the fat bodies are made up of polygonal cells. The cells, together they prosper old, end up being filled up through minute urate crystals.

Excretory organ # 8. Exoskeleton:

In Crustaceans and Insects, the cell of the hypodermis secrete nitrogenous building materials which continue to be de­posited in ~ the exoskeleton. This are removed at the time of ecdysis.

Excretory organ # 9. Minister Caeca:


In Squilla, the rec­tum bears a pair of intestinal caeca having a comb-like interior wall. These are believed to it is in excretory in function.

Excretory organ # 10. Midgut Epithelium:

In Nauplius lar­vae the Crustacea, the cells bordering the midgut lug out excretory function.

Excretory body organ # 11. Pericardial Cells:

In Insects part cells roughly the heart and also the pericardial mem­brane space excretory in function.

Excretory body organ # 12. Nephrocytes:

These space migratory cells, existing in teams within the haemocoel that insects. These are concerned as modification fat human body cells and also are said to absorb undesirable colloidal corpuscle from the blood.

Excretory body organ # 13. Oenocytes:

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In Insects and also Myriapods, particular cells are uncovered in groups roughly the abdominal muscle spiracles. This cells originate from surface epithelium and are thought to be both excretory and also circulatory in functions. The excretory mechanism is well-developed in land-living arthropods, i m sorry are concerned with the problem of water loss. In them the excretory organs job-related in together a means that very little water is lost from the body.