Insect antennae

Filiform antenna is the most basic type found very common in the insect world. This is typically elongated and composed uniform segments and appear thread-like shape.Example: Ground beetles and cockroaches. (Ground beetles are so called because many species do not fly and lack hind wings).

Filiform Antenna-Thread-like antenna

Solitary bee   Assassin Bug

Aristate Antenna – Pouch like antenna

Latin, Arista = awn

Aristate antennae are pouch-like with a lateral bristle. The last segment of the flagellum is enlarged and bears bristle or arista.Eg. House flies

CAPITATE ANTENNAE – KNOBBED ANTENNAE

The proximal segments of the flagellum are uniform is size while the segments of the distal end modify into a large knob or capitulum.

Eg. Chalcids, Butterflies, Antlions, Owlflies, etc.

This is another type of club but in this case, the terminal segments are distinctly and abruptly enlarged.

The segments start off narrow and gradually become wider towards the tip of the flagellum. This may be gradual along its length, or a sudden increase and therefore mainly affecting the last few segments giving the appearance of a club.

Ex: 1. Carrion beetles (adults generally feed on decaying animal matter or on the maggots that feed on carrion) 2. water scavenger beetles (Hydrohilus triangularis)

(Hydrohilus triangularis) Carrion beetles

Clavate antenna – Clubbed antenna

Geniculate antenna – Elbowed antenna

Clearly, the geniculate antennae have a distinct abrupt bend or elbow part down the length. The first segment (segment that attaches to the head-arrow) is elongated and much longer the remaining segments. Eg. Most ants, weevils and some beetles.

Weevil

Moniliform antennae – Bead like antenna

 Moniliform antennae are the beadlike antennae, look rather like a string of pearls This form of antenna is found in termites and some beetles.

Termite (Pterotermes occidentis)

Setaceous Antenna-Bristle/whip like antenna

Dragonfly

The antennae are hair-like, tiny and almost invisible to the naked eye. There are many joints. The flagellar segments taper gradually from the base to the tip . i.e., Setaceous antennae have a bristle/whip-like shape.Eg. Dragonflies, Bristletails, Cockroaches, Mayflies, Stoneflies, Caddishflies, Cicadas, etc.

Cicada (Cacama valvata)

Pectinate Antenna- Comb like antenna 

Click Beetle

The segments are longer on one side (uni pectinate) or on both the sides (bipectinate). This gives the appearance of a comb. The lateral extensions are called rami.

Eg. Sawflies, Beetles, Glow-worms, silkmoth (bipectinate), etc.

Serrate Antenna-Saw-toothed antenna

Firefly with Serrate Antennae

The segments are trianglar with uncentric arrangement either on one side (uniserrate) or on both the sides (biserrate) giving the appearance of a saw edge. Eg.Click beetle, longicorn beetle, firefly, etc.

Lamellate Antenna-Fan/Leaf like antenna 

This is a type of asymmetrically clubbed antennae where the terminal club is composed of several rounded sheet-like lobes that are expanded laterally. This gives the appearance of a fan/leaf. Eg. Beetles

Scarab Beetle

Flabellate Antenna 

This type is similar to lamellate but differing in that the terminal lobes are parallel-sided and are not capable of being rolled into a tight fitting ball. Eg. Stag beetles.

Stag Beetle

Each of the segments have a number of fine thread-like hair. This gives the appearance of a feather. i.e., Plumose antennae have a brush or feather-like shape.Example: Moths, Flies and male mosquitoes.

Plumose-Feather like

Some Uncommon antennae