Morphology of Diptera

The Order Diptera is characterized by a substantial morphological uniformity, which often makes it difficult to recognize lower taxa, especially at the level of species or genus.

I: head; II: thorax; III: abdomen.

1: prescutum; 2: anterior stigma; 3: scutum; 4: basicosta; 5: calyptra; 6: scutellum; 7: alary nerve (costa); 8: ala; 9: urite; 10: haltere; 11: posterior stigma; 12: femora; 13: tibia; 14: spur; 15: tarsus; 16: propleura; 17: prosternum; 18: mesopleura; 19: mesosternum; 20: metapleura; 21: metasternum; 22: compound eye; 23: arista; 24: antenna; 25: maxillary palpi; 26: labrum (inferiore); 27: labellum; 28: pseudotrachae; 29: tip.

Adults are small (< 2mm.) to medium sized insects (- < 10mm.), larger Diptera are rare, only certain families of Diptera Mydidae and Pantophthalmidae reach 95–100 mm wingspan while tropical species of Tipulidae have been recorded at over 100 millimetres. They have dull or bright colors, uniform or variegated and are sometimes mimetic such as in Syrphidae . Of fundamental importance, for taxonomy, is the presence and distribution of the attached integumental bristles.

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