A beetle leg

External body part, or natural prolongation, that protrudes from an organism's body.

- Appendage

268 related topics


Limb (anatomy)

Diagram of a typical synovial joint

A limb (from the Old English lim), or extremity, is a jointed bodily appendage that humans and many other animals use for locomotion such as walking, running and swimming, or for prehensile grasping or climbing.


The tail of Nephrops norvegicus – the uropods flank the telson; a diaeresis is visible on the exopod (outer part) of each uropod.

Uropods are posterior appendages found on a wide variety of crustaceans.


One of two gonopods of the greenhouse millipede (Oxidus gracilis). Scale bar: 0.2 mm or approximately 1/127 in
Paired gonopods (g) on the male genitalia of Corydalus cornutus
Gonopod diversity in 20 Chaleponcus species (Spirostreptida, Odontopygidae) from Tanzania
Gonopod development in Nopoiulus kochii (Julida, Blaniulidae). A: juvenile with walking legs on segment 7 (asterisk). B: subsequent stage with walking legs replaced by gonopod primordia. C: adult stage with gonopods (colored) in place of walking legs.

Gonopods are specialized appendages of various arthropods used in reproduction or egg-laying.


Arthropods (, (gen.

Structure of a biramous appendage.
Alignment of anterior body segments and appendages across various arthropod taxa, based on the observations until mid 2010s. Head regions in black.
Illustration of an idealized arthropod exoskeleton.
Cicada climbing out of its exoskeleton while attached to tree
Arthropod eyes
Head of a wasp with three ocelli (center), and compound eyes at the left and right
Compsobuthus werneri female with young (white)
The nauplius larva of a penaeid shrimp
Marrella, one of the puzzling arthropods from the Burgess Shale
The velvet worm (Onychophora) is closely related to arthropods
Insects and scorpions on sale in a food stall in Bangkok, Thailand

ποδός)) are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages.

Antenna (biology)

Large antennae on a longhorn beetle
Cutaway diagram of a barnacle, with antennae highlighted by arrow
Terms used to describe shapes of insect antennae
Antennal shape in the Lepidoptera from C. T. Bingham (1905)
Electron micrograph of antenna surface detail of a wasp (Vespula vulgaris)
Olfactory receptors (scales and holes) on the antenna of the butterfly Aglais io, electron micrograph

Antennae ( antenna), sometimes referred to as "feelers", are paired appendages used for sensing in arthropods.


Arthropod group which also includes millipedes and other multi-legged creatures.

Underside of Scolopendra cingulata, showing the forcipules
Close-up of the tail-like rear pair of legs of a centipede
A representative millipede and centipede (not necessarily to scale)
A centipede protecting her first instar offspring
A centipede (Scolopendra cingulata) being eaten by a European roller
A juvenile centipede seen on vegetation at Agumbe, Karnataka, India
Centipedes at Wangfujing market
Man holding Scolopendra gigantea. Trinidad, 1961

These limbs, or maxillipeds, end in sharp claws and include venom glands that help the animal to kill or paralyze its prey.

Arthropod leg

Diagram of biramous leg of a trilobite; Agnostus spp.
Crustacean appendages
Micrograph of housefly leg
Diagram of a spider leg and pedipalp – the pedipalp has one fewer segment
The leg of a squat lobster, showing the segments; the ischium and merus are fused in many decapods
Seven-segmented legs of Scutigera coleoptrata
Zabalius aridus showing full leg anatomy, including plantulae under each tarsomere
Diagram of a typical insect leg
Acanthacris ruficornis, legs saltatorial, femora with bipennate muscle attachments, spines on tibiae painfully effective in a defensive kick
Robber fly (Asilidae), showing tarsomeres and pretarsi with ungues, pulvilli and empodia
Webspinner, Embia major, front leg showing enlarged tarsomere, which contains the silk-spinning organs
Bruchine with powerful femora used for escape from hard-shelled seed
Expression of Hox genes in the body segments of different groups of arthropod, as traced by evolutionary developmental biology. The Hox genes 7, 8, and 9 correspond in these groups but are shifted (by heterochrony) by up to three segments. Segments with maxillopeds have Hox gene 7. Fossil trilobites probably had three body regions, each with a unique combination of Hox genes.

The arthropod leg is a form of jointed appendage of arthropods, usually used for walking.

Arthropod mouthparts

The mouthparts of arthropods have evolved into a number of forms, each adapted to a different style or mode of feeding.

The face of a caterpillar with the mouthparts showing.
Figure 1: Chewing mouthparts of a grasshopper.
Legend: lr, labrum; md, mandibles; mx, maxillae; hp hypopharynx; lb, labium.
Figure 2: Ventral view of forcipules of a centipede, arising from the first body segment
Figure 3: The mouthparts of an edible crab: the third maxillipeds conceal the remaining mouthparts
Figure 4: Types of chelicerae: (A) jackknife, (B) scissor, and (C) 3-segmented chelate

Most mouthparts represent modified, paired appendages, which in ancestral forms would have appeared more like legs than mouthparts.

Decapod anatomy

Made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon .

Folded abdomen of a cooked crab severed from its body, showing its pleopods hiding beneath.

Each segment may possess one pair of appendages, although in various groups these may be reduced or missing.


A white-tailed deer's tail
Vulpes lagopus (Arctic fox) sleeping with its tail wrapped as a blanket.
Lion (Panthera leo)
Pig (Sus domestica)
Glyptodon (Glyptodon asper)
Longhorn cowfish (Lactoria cornuta)
Grévy's zebra (Equus grevyi)
American alligator (Alligator mississipiensis)
Hippopotamus (Hippopotamus amphibius)

The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso.