This species name is from the Greek 'makros' meaning long and 'dactylos' meaning finger or toe.
The following is the decription of Breviceps usambaricus (Barbour and Loveridge, 1928), which was synonymized with Probreviceps macrodactylus by Parker (1934):
Habit is short and stout; head is small. Snout is fairly prominent, measuring 8.1 (6.1 to 8.4 in registered paratype series) times into body length and projecting beyond the lower lip, which is nearly vertical. Eye is small, diameter is 11 times into body length (9 to 15 times in paratype series). Interorbital width is one and a third times the width of the upper eyelid. Tympanum is distinct but ill defined (round and well defined in some paratypes, very difficult to distinguish in young), sub-circular, its diameter about two-thirds that of the eye-opening. Fingers and toes are moderately slender, bluntly rounded at the tips. A series of pads are present beneath the fingers and toes, and a very small tubercle is at each articulation of fingers and toes. Palms of hands have larger blister-like folds; soles of feet have small, rounded, rather indistinct granules. Fourth finger is minutely longer than second (equal to or slightly shorter in paratypes); fifth toe is longer than first. A large (4 mm.) pebble-like inner metatarsal tubercle and a flat, inconspicuous, separated outer metatarsal are present. The tarsal tubercle of the adpressed hind limb reaches the eye (also in 20 of 25 paratypes examined, the tympanic region in No. 13717, the nostril in Nos. 13723, 13724 and 13729). Dorsal skin is rugose or granular frarely almost smooth. Skin on venter is smooth, except edges of chin and soles of feet, which have numerous scattered granules. Coloration in alcohol is uniformly purplish above and on throat. Venter is lighter, variegated with brown and purplish-brown. Some light spots are present on the purplish throat.
The female holotype of Breviceps usambaricus measured 65 mm from snout to vent, and the twenty-four paratypes ranged in size from 29 to 60 mm (Barbour and Loveridge, 1928). Males reach 40 mm and large females up to 65 mm in length (Channing and Howell, 2006).
Diet includes ants and beetles (Barbour and Loveridge, 1928). This species is preyed upon by Torneri's cat snake Crotaphopeltis tornieri (Channing and Howell, 2006).
This species is endemic to the Eastern Arc Mountains of Tanzania, and it has been recorded from the Usambara, Nguru, Udzungwa and Uluguru Mountains (Tanzaniaherps.org).
This species breeds during the small rains in November. Eggs are deposited in the burrow; there is no tadpole stage, eggs develop directly into juveniles (Channing and Howell, 2006).