The 13 Forms of Insect Antennae

The 13 Forms of Insect Antennae Antennae are movable sensory organs located on the head of most arthropods. All insects have a pair of antennae, but spiders have none. Insect antennae are segmented, and usually located above or between the eyes. How Do Insects Use Antennae? Antennae serve different sensory functions for different insects. In general, the antennae might be used to detect odors and tastes, wind speed and direction, heat and moisture, and even touch. A few insects have auditory insects on their antennae, so theyre involved in hearing.  In some insects, the antennae may even serve a non-sensory function, such as grasping prey. 13 Different Shapes Because antennae serve different functions, their forms vary greatly within the insect world. In all, there are about 13 different antennae shapes, and the form of an insects antennae may be an important key to its identification. Learn to differentiate the forms of insect antennae, and it will help you improve your insect identification skills. Aristate Are Pouch-Like Aristate antennae are pouch-like, with a lateral bristle. Aristate antennae are most notably found in the Diptera (true flies). Capitate Have a Prominent Club or Knob at Their Ends Capitate antennae have a prominent club or knob at their ends. The term capitate derives from the Latin caput, meaning head. Butterflies (Lepidoptera)  often have capitate form antennae. Clavate Have a Gradual Club or Knob The term clavate comes from the Latin  clava, meaning club. Clavate antennae terminate in a gradual club or knob (unlike the capitate antennae, which end with an abrupt, pronounced knob). This antennae form is found most often in beetles, such as in carrion beetles. Filiform Are Slender and Thread-Like The term filiform comes from the Latin filum, meaning thread. Filiform antennae are slender and thread-like in form. Because the segments are of uniform widths, there is no taper to filiform antennae. Examples of insects with filiform antennae include: rock crawlers (order Grylloblattodea)gladiators (order Mantophasmatodea)angel insects (order Zoraptera)cockroaches (order Blattodea) Flabellate Look Like a Folding Paper Fan Flabellate  comes from the Latin flabellum, meaning fan. In flabellate antennae, the terminal segments extend laterally, with long, parallel lobes that lie flat against one another. This feature looks like a folding paper fan. Flabellate (or flabelliform) antennae are found in several insect groups within the Coleoptera, the Hymenoptera, and the Lepidoptera. Geniculate Are Bent or Hinged Sharply Geniculate antennae are bent or hinged sharply, almost like a knee or elbow joint. The term geniculate derives from the Latin genu, meaning knee. Geniculate antennae are found mainly in ants or bees. Lamellate Are Flattened and Nested The term lamellate comes from the Latin lamella, meaning a thin plate or scale. In lamellate antennae, the segments at the tip are flattened and nested, so they look like a folding fan. To see an example of lamellate antennae, look at a scarab beetle. Monofiliform Look Like Strings of Beads Monofiliform comes from the Latin monile, meaning necklace. Moniliform antennae look like strings of beads. The segments are usually spherical, and uniform in size. The termites (order Isoptera) are a good example of insects with moniliform antennae. Pectinate Have a Comb-Like Shape The segments of pectinate antennae are longer on one side, giving each antennae a comb-like shape. Bipectinate antennae look like two-sided combs. The term pectinate derives from the Latin pectin, meaning comb. Pectinate antennae are found mainly in some beetles and sawflies. Plumose Have  a Feathery Appearance The segments of plumose antennae have fine branches, giving them a feathery appearance. The term plumose derives from the Latin pluma, meaning feather. Insects with plumose antennae include some of the true flies, such as mosquitoes, and moths. Serrate Look Like a Saw Blade The segments of serrate antennae are notched or angled on one side, making the antennae look like a saw blade. The term serrate derives from the Latin serra, meaning saw. Serrate antennae are found in some beetles. Setaceous Are Bristle-Shaped The term setaceous comes from the Latin seta, meaning bristle. Setaceous antennae are bristles of insects with setaceous antennae include mayflies (order Ephemeroptera) and dragonflies and damselflies (order Odonata). Stylate Terminate in a Long, Slender Point Stylate  comes from the Latin  stylus, meaning pointed instrument. In stylate antennae, the final segment terminates in a long, slender point, called a style. The style may be hairlike but will extend from the end and never from the side. Stylate antennae are found most notably in certain true flies of the suborder Brachycera (such as robber flies, snipe flies, and bee flies). Source: Triplehorn, Charles A. and Johnson, Norman F. Borror and DeLongs Introduction to the Study of Insects. 7th Edition