Fig. 4

Transmission of symbionts from hemolymph to mature oocytes in different cicada species. A to D For E. coelestia, Arsenophonus together with Sulcia and Hodgkinia were transported to the posterior pole of the mature oocytes, migrating through the cytoplasma of epithelial plug cells into the perivitelline space and finally formed a characteristic “symbiont ball” in each egg. E to H For Te. sp., Sulcia and Hodgkinia were transported to the posterior pole of the mature oocytes, migrating through the cytoplasma of epithelial plug cells into the perivitelline space and finally formed a “symbiont ball” in each egg. I to L For K. caelatata, Sulcia and YLS were transported to the posterior pole of the mature oocytes, migrating through the cytoplasma of epithelial plug cells into the perivitelline space and finally formed a “symbiont ball” in each egg. M to P For Ta. sp., Sulcia and YLS were transported to the posterior pole of the mature oocytes, migrating through the cytoplasma of epithelial plug cells into the perivitelline space and finally formed a “symbiont ball” in each egg. Q to T For G. tienta, Sulcia and YLS were transported to the posterior pole of the mature oocytes, migrating through the cytoplasma of epithelial plug cells into the perivitelline space and finally formed a “symbiont ball” in each egg. U to X For H. maculaticollis, Sulcia and YLS were transported to the posterior pole of the mature oocytes, migrating through the cytoplasma of epithelial plug cells into the perivitelline space and finally formed a “symbiont ball” in each egg. Abbreviations: A, Arsenophonus; H, Hodgkinia; S, Sulcia; Y, yeast-like fungal symbiont; EPC, epithelial plug cell; FC, follicular cell; SB, symbiont ball. Red arrows representing the emigration of the symbionts from hemolymph to perivitelline space