Drosophila melanogaster (subgenus Sophophora), a well studies model organism, utilizes fermenting fruits as its substrate, while Drosophila virilis (subgenus Drosophila) has evolved to use fermenting tree sap (slime flux) as its primary substrate. Compared to D.melanogaster, significantly less information is available about the ecology and evolutionary shifts in D.virilis that enables it to utilize a different niche. To understand these major evolutionary changes, we collected tree sap from multiple field sites. In the saps, we identified 80 volatile compounds by using gas chromatographic-mass spectrometric (GC-MS) analysis. Several of the identified odors turned out to be behaviorally active. One compound in particular, 2,6-dimethoxyphenol (syringol) significantly attracted both larval and adult stages of D.virilis, while being repellent to D. melanogaster. Furthermore, exposure to syringol triggered deposition of droplets containing the aggregation pheromone, (Z)-10-heneicosene, by males. Next, we carried out antennal screening with a panel of 57 compounds using single sensillum recording technique (SSR), and could identify 10 different sensillum classes. In comparison to D. melanogaster sensillum types, we did not find an ab3-like sensillum class. Interestingly, it has been reported that the broadly tuned olfactory receptor Or22a, expressed in the ab3 sensillum type in species from the D. melanogaster subgroup, is not expressed in D.virilis. We also observed a significant overexpression of an ab9-like sensillum class that is characterized by a broad tuning profile. In conclusion, we reveal specific behavior towards sap-related odors and demonstrate that peripheral coding in D.virilis is different as compared to D.melanogaster with deletions, additions and response changes among sensillum classes.