Boulengerula boulengeri Tornier, 1896
Both the genus and species are named for G.A. Boulenger, a herpetologist from the Natural History Museum in London.
A pale blue to grey caecilian that is darker above than below, from 80 to 250 mm in length. The mouth is recessed and the tail is absent. The heads of males are slightly larger than females, although the sexes are hard to tell apart in other ways. Oviductal eggs are visible through the skin of females. Primary annuli vary from 124 to 134 (Harper et al., 2010).
This is predominantly a fossorial, or burrowing, species.
Adults are bluish-grey above with a darker band along the back. Venter is bluish-grey, except for the throat, which is a pinkish flesh-color. Young are much more worm-like in appearance as they are largely pinkish flesh-color with the dorsal band showing pinkish-mauve (Barbour and Loveridge, 1928).
Males range from 142 to 242 mm in snout-vent length, while females are slightly larger, ranging from 150 to 229 mm (Harper et al., 2010).
Adults are known to eat mostly termites and earthworms, but will take on most soil invertebrates which they find in their galleries, including large crickets which they spin to reduce the size so that it can fit into their mouths. Predators include the Usambara Garter Snake Elapsoidea nigra, which may predate solely upon caecilians. However, the most abundant predators are almost certainly invertebrates, including safari ants (Dorylus molestus; Harper et al., 2010).
This species is distributed in the East and West Usambara Mountains and on the Magrotto Ridge (Harper et al, 2010).
It is a common species in the Usambaras and is found in the soil (typically the top 20 cm) in forests and on smallfarms. It is absent from compacted soils (e.g. tea plantations), but can penetrate very hard forest soils to depths > 50 cm. It is found at elevations between 300 and 1500 m (Harper et al., 2010).
B. boulengeri lays eggs in a nest in moist soil that hatch directly into small pink caecilians. This species may have extended parental care with hatchlings feeding from the skin of their brooding mother, as reported for B. taitana. Eggs have been found in December and pink juveniles with their mothers during December and January, within the short rainy season (Harper et al., 2010).