overlaps develops from sends synaptic output to region receives synaptic input from neuron sends synaptic output to cell optic cartridge medulla layer M1 medulla layer M5 medulla layer M6 photoreceptor cell R7 Inner photoreceptor cell of the ommatidium whose rhabdomere is located distally, directly above that of R8 (Wernet and Desplan, 2004). It has a single axon that extends through a single column of the lamina without making synapses (Fischbach and Dittrich, 1989). This axon crosses the first optic chiasm and extends through a single column of the medulla where it makes pre-synaptic contacts, mainly in medulla layers M1 and M5 (Takemura et al., 2008), before terminating in M6 (Gao et al., 2008; Sancer et al., 2019). It forms reciprocal inhibitory histaminergic synapses with the R8 photoreceptor of the same optic column (Schnaitmann et al., 2018), with a large proportion in the first optic chiasm (Kind et al., 2021). This term refers to a type of adult eye photoreceptor cell, defined based on the position of its rhabdomere within each ommatidium - see figure 4 in Wolff and Ready (1993). It does not refer to Rh7-expressing photoreceptors. fly_anatomy.ontology VFB:FBbt_00004225 R7 receptor cell R7 FlyBrain_NDB:10112 lamina receptor cell R7 FBbt:00004225 CL:0000707 R7 FBbt:00003716 photoreceptor cell R8 first optic chiasma inner photoreceptor cell photoreceptor R7 precursor cell