## 3 Volatile Pheromones
### Composition of Volatile Pheromones

Table 1: List of tephritid species for which volatile pheromone has been chemically analysed from the headspace. \begin{table}
\begin{tabular}{c c c c} \hline
**Genus** & **Species** & **Sex** & **References** \\ \hline _Anastrepha_ & _A. fraterculus_ & Male * & [227] \\  & _A. ludens_ & Male * & [182] \\  & _A. ludens_ & Male * & [228] \\  & _A. ludens_ & Male * & [183] \\  & _A. ludens_ & Male * & [185] \\  & _A. ludens_ & Male * & [184] \\  & _A. suspena_ & Male * & [203] \\ \hline \end{tabular}
\end{table} 
Table 2: List of tephritid species for which pheromones have been derived from rectal glands extracts. The two most represented chemical classes of the volatile compounds captured in the headspace in _Anastrepha_, _Bactrocera_, _Certainis_, _Rhagoletis_ and _Zeugodacus_ species are fatty acyls and organooxygen compounds. Prenol lipids, which represent most compounds in _Ceratitis_ and _Anastrepha_ species, and are abundant also in _Rhagoletis_, are instead poorly represented in _Bactrocera_ and absent in the emissions of _Z. cucurbitae_. Lactones are particularly abundant in _Anastrepha_ species (Table S1). Within each genus, it is evident that only few compounds are shared among species (Figure 4). For example, in all four _Ceratitis_ species investigated so far, namely _C. capitata_, _Ceratitis fascicuntris_ (Bezzi), _Ceratitis anonne_ (Graham), and _C. rosa_, only three volatile chemicals, all belonging to the prenol lipid class, are emitted by males. These three compounds are linalool, (_E_)-\(\beta\)-ocimene, and (_Z_)-\(\beta\)-ocimene that also occur naturally in the host plants. In C. _capitata_, the perception of plant volatiles has been investigated by electroantennogram (EAG) and behavioural studies demonstrating that linalool, a compound representative of immature citrus fruit associated with high toxicity against immature stages of fruit flies and considered as an important compound conferring resistance against fruit fly larval \begin{table}
\begin{tabular}{c c c c} \hline
**Genus** & **Species** & **Sex** & **References** \\ \hline _Bactracen_ & _B. albistrigata_ & Male & [229] \\ _B. accuminata_ & Male & [230] \\ _B. carambloae_ & Male & [72] \\ _B. correcta_ & Male/Female & [231] \\ _B. correcta_ & Male & [232] \\ _B. distincta_ & Male & [230] \\ _B. dorsalis_ & Male & [68] \\ _B. dorsalis_ & Male & [229] \\ _B. facialis_ & Male & [233] \\ _B. halfordiae_ & Male & [234] \\ _B. kirki_ & Male & [233] \\ _B. knutassi_ & Male & [233] \\ _B. lairfrons_ & Male & [234] \\ _B. musae_ & Male/Female & [76] \\ _B. neolnumeralis_ & Male & [209] \\ _B. nigrotbiialis_ & Male & [229] \\ _B. occipitalis_ & Male & [234] \\ _B. oleae_ & Male/Female & [79] \\ _B. oleae_ & Male/Female & [85] \\ _B. oleae_ & Female & [230] \\ _B. oleae_ & Male/Female & [85] \\ _B. oleae_ & Male & [235] \\ _B. oleae_ & Female & [174] \\ _B. passiflora_ & Male & [233] \\ _B. tryoni_ & Male & [209] \\ _B. tryoni_ & Female * & [210] \\ _B. tryoni_ & Female & [211] \\ _B. tryoni_ & Male & [212] \\ _B. tryoni_ & Male/Female & [236] \\ _B. umbrosa_ & Male & [237] \\ _B. xanthodes_ & Male & [233] \\ \hline _Zeugodacus_ & _Z. cucumis_ & Male & [234] \\ _Z. cucurbitae_ & Male & [238] \\ _Z. cucurbitae_ & Male & [239] \\ _Z. cucurbitae_ & Male & [237] \\ _Z. tau_ & Male & [237] \\ \hline _Ceratitis_ & - & - & - \\ \hline _Rhagoletis_ & - & - & - \\ \hline \end{tabular}
\end{table} 
Table 2: _Cont._development, has a significant deterrent effect [240]. Linalool was reported by numerous studies as an active constituent of medfly male sex pheromone that elicits a strong EAG response [218; 221; 241]. It also triggers antennal depolarisation in females of _C. fasciventris_, _C. anonae_ and _C. rosa_ (so-called _Ceratitis_ FAR complex) [214]. Figure 4: Overlap among chemicals identified in the headspace emissions of tephritids.