Cerodontha Rondani, 1861
Cerodontha species always feed on Monocotyledoneae, most of them on Poaceae and Cyperaceae.
In 1973 the current concept of the genus was formulated, seven taxa previously considered as separate genera or subtaxa in other genera were subsequently subsumed under Cerodontha (Nowakowski, 1973). One of these, Xenophytomyza, is now treated as synonym of the Subgenus Cerodontha.
Butomomyza Nowakowski, 1967
Dizygomyza Hendel, 1920
Icteromyza Hendel, 1931
Poemyza Hendel, 1931
Phytagromyza Hendel, 1920
Cerodontha Rondani, 1861 (=Xenophytomyza Frey, 1946)
Of these subgenera, especially the monophyly of Poemyza and Cerodontha is well supported by phylogenetic results. The more ancient forms can be found within Butomomyza and Dizygomyza whereas more derived taxa were placed in the subgenera Poemyza and Cerodontha. On this CD-ROM only the latter two subgenera are treated because species of economic importance occur only there.
Adult morphology
Most species are rather dark; the wing venation is normally complete, although there is a wide spectrum of forms within this genus. Certain morphological peculiarities are found in some of the subgenera. Of these the third antennal segment is often enlarged in males; lunule semicircular or higher than semicircular, either narrow or triangular in shape; (also see Subgenus Poemyza). In the Subgenus Cerodontha there is normally only one pair of scutellar bristles.
Male terminalia
All species possess a pair of unique processes situated within the epandrium below the cerci, called "processi longi" (Sasakawa, 1961) or "Langfortsätze" (Nowakowski, 1973). Cer denticornis epandrium.pct that can be interpreted as apomorphy. Possibly they are derived from the inner part of the surstyli, whereas only the outer component of them is fused with the epandrium. Recently, Boucher, 2002 introduced the English term subepandrial sclerites for the structures in Cerodontha that can be recommended for the English literature.
Epandrium rather long apically tapering; surstyli of variable size, fused with epandrium below the epandrium's tip. Distiphallus with terminal tubules being usually very long and characteristically 's'-shaped bent Cer incisa aedeagus.pct.
Immature stages
Most of the larvae can easily be identified by the greatly flattered, blade-like head segment. Those species are specialized in feeding on extremely thin plant cell layers. Denticles of the locomotion welts often not thorn-like as in most agromyzid larvae but rather developed as flattened scales. The cephalopharyngeal skeleton is usually long and slender Cerodontha ceph.pct.
Mouth hooks always alternating, normally four of nearly equal size and shape. Cephalic segment very strong, laterally flattened; frontal hairs long and slender, apically bent backward (Cer denticornis Larva SEM1.pct). Most species have posterior spiracles with three more or less elongated bulbs (Cer incisa Larva SEM.pct). The bulbs of the anterior spiracles are normally situated in a single row, well separated from each other. Puparia are normally thick-walled and dark brown or black colored. Pupariation occurs always in the mine.
Bionomics
Most species are leaf miners on species of the Monocotyledoneae families Cyperaceae, Iridaceae, Juncaceae and Poaceae. Pupation always occurs within the mine. As reported in the description of the immature stages, this group can be considered as highly specialized in the leaf-mining feeding habit. However, even in this genus stem mining species living in grass-stalks have evolved (von Tschirnhaus, 1991, Nowakowski, 1973). Most probably their ancestors were leaf miners inhabiting leaf sheaths of grasses, which are wrapping the stalks. Their larval mouthparts underwent a significant change towards the typical appearance of stem mining species.