Commonly known as Chalice Vine (Solandra grandiflora) a member from a nightshade family which is infamous for the toxic plant reputation. It is more like are admire and enjoy the beauty and not an edible type.
I had not come across any fragrance and often mentioned in other websites that it has fragrance.
Perhaps mistaken for Solandra Maxima where the flower bloom is much more open like an umbrella. I had come across that flower and found that it has a lovely fragrance.
Also this does not bare fruits or seeds. Most likely the bats are polinators and these particular bat species are not found here in my tropical region. I often noticed stingless bees visit these flowers early in the morning at their first bloom where the flowers appear to be more cream white tones.
Later at the second and third day - the flowers appear to be more on the darker yellow tones as they age, soon after the flower fall off to the ground withered.
These are hardy climbing plant which can be heavy and may need spiking or some sort of support when they grow bigger. Also they can be leggy and messy especially stem growing everywhere and therefore a good pruning and identifying some form of direction & shape will be good for this plant.
Light: This plant requires direct sunlight for it to grow and bloom. It will not do well in total shade and may not bloom at all in shaded condition.
Watering: A good watering is required based on the size of the plant. When lacking water, the new shoots and leaves will appeared withered.
Feeding: A regular feeding regime will ensure constant blooming cycle for this particular plant.
The best method is use semi-wood cutting and sometimes aerial roots will appear and that would be a good place to take cuttings for better growth. Also propagating the stem in water will encourage roots to grow. I would say this is a hardy plant and may be considered invasive if not checked and kept in proper control. They can grow wildly - do consider a good spacious growing space as it can be a huge big climbing plant.
Do prune after the blooming season to ensure a better growth and more blooms. Do not allow the plant to focus it's energy on new shoot growth or else it will discount on the number of the flowers forming from the vine. The best is to keep it small and compact as there will be more flowers and less vine growing everywhere.
Overall I would say it is an easy plant to grow. Once established there is nothing much care is needed except the periodic pruning regime. This is a hardy plant also I noticed that it is without any pest problems compared to so many other flowering plants - this one fares well.