Table 2. Reports using various techniques (microscopy, antibodies or molecular probes, liquid chromatography (LC) and mass spectrometry (MS)) showing the nerve going to the crop and in some cases its content.

Technique used	Species	References
A. Microscopy (light, TEM, SEM)
Light microscopy/dissection	mosquito	[86]
	Calliphora erythrocephala	[87]
	Glossina morsitans	[88]
	Glossina brevipalpis	[89]
SEM and TEM	Phormia regina	[11]
B. Immunostaining
Insulin-like peptide	Drosophila melanogaster	[90]
	Aedes aegypti	[91]
Serotonin	Stomoxys calcitrans	[92]
Anti-AKH antibody	D. melanogaster	[68]
C. Molecular, LC + MS
Ilp2-Gal4	D. melanogaster	[93]
Diuretic hormone 44 (Dh44),	D. melanogaster	[94]
Myosuppressin	Drosophila suzukii	[70]