This HII region is ionised by the O6 Ia supergiant HD 152386
according to a 1999 paper by Benaglia and Cappa. SIMBAD says that this is in fact a Wolf-Rayet star, WR 79b.
RCW 110 and RCW 111 are condensations within the larger Gum 54 nebula.
Gum 54 can be seen in this MSX infrared image
The O6.0 Ia f star HD 152386 is associated with Gum 54 according to a 1999 paper by Benaglia and Cappa. They give a photometric distance of 2500 parsecs for the star and suggest a distance of 2800 for an atomic hydrogen (HI) bubble that appears to be surround the region. [1
Gum 54 (RCW 110-111) consists of several condensations bathing in a diffuse nebulosity.[2
1. ^ Benaglia, P. & Cappa, C. E. (1999). "Possible wind blown bubbles
associated with five Of stars", Astronomy and Astrophysics, Vol. 346,
2. ^ Georgelin, Y. M., Russeil, D., Marcelin, M., et al. (1996). "Deep Hα
survey of the Milky Way. III. The l=338deg area.", Astronomy and
Astrophysics Supplement Series, Vol. 120, 41-56. [1996A&AS..120...41G]