Figure 1.

The symbiont-harboring midgut crypts of Physopelta gutta. (A) An adult female P. gutta. (B) The dissected midgut of an adult female P. gutta. The Burkholderia symbiont is specifically localized in the 4th section of the crypt-bearing midgut [31]. (C) An enlarged image of the M4 section. (D,E) Pre-culture of the midgut crypts in yeast-glucose medium. The midgut crypts before pre-culture (D) and after two days of pre-culture (E). After pre-culture, the crypts became cloudy due to the bacterial growth inside the crypts. Bacterial growth was also observed outside the crypts. M1, midgut 1st section; M2, midgut 2nd section; M3, midgut 3rd section; M4, midgut 4th section; M4B, M4 bulb; MT, malpighian tubule; H, hindgut.