Thorax of Mosquito Larvae

The thorax is generally globular and wider than the head. The setae of the prothorax are numbered 0-P to 14-P. Seta 0-P is generally small and borne laterally behind setae 4,5-P. Setae 1-3-P are frequently used in classifying anophelines, Culex and certain Uranotaenia. Setae 1-7-P have been used to distinguish certain species of tribe Aedini. The pleural setal group, setae 9-12-P,M,T, on all three of the thoracic segments are useful in classifying Anopheles. The metathoracic setal group is unusually small and useful in distinguishing larvae of genus Opifex. Other setae of importance include the presence or absence of seta 8-M and the development of setae 11-P,M,T and seta 13-T. The positional relationships of setae are sometimes important as well. The thoracic integument sometimes bears a covering of small spicules. A feature peculiar to anopheline larvae is the pectinate branching of most of the larger setae. In many anophelines seta 3-T is palmate. Seta 1-M is also palmate in species of Chagasia.