Collocalia sp - Glossy Swiftlet

Even though it is a bad image, taken from a long distance, I have added it to possibly help with ID issues. The significance of this image, is that it shows the tail feathers spread. You can see longitudinal light stripe markings, but these could just be interpreted as light reflections, but there are no white spot markings revealed.

There are two genus in question:

Collocalia esculenta sp. – distributed throughout S.Asia except for Java. Noted for low altitude. Tail feathers have no spot markings.

Collocalia linchi linchi – distribution; Java, Madura, Nusa Penida and Bawean islands. No mention of altitude found. Tail feathers have concealed white spot markings near base.

The Collocalia sp. Specimens in these images were photographed at an altitude of 985m. It is possible that even with the tail extended, that the spots are still not visible, but I consider this unlikely, otherwise there would be no evolutionary significance for the markings.

Location and Altitude point away from Esculenta, leaving us with a quotable genus and species. Without the spots, we are left with Esculenta and a species overlooked that has adapted to altitude.

Location is Bandung, West Java, Indonesia. Alongside a stream and paddy fields.