Comprehensive DescriptionRead full entry
Diagnosis: Breviceps macrops has a globose body, short snout and large eyes. It can be distinguished from other rain frogs in southern Africa by the combination of a smooth venter with a transparent vascular window (this character alone distinguishes it from all except B. namaquensis; see photo of the venter in Du Preez and Carruthers 2009); a weakly developed (if present) single basal subarticular tubercle on the hand (double in B. namaquensis); specialized feet, which are paddle-like and smooth and have thick fleshy webbing (unique to B. macrops); exceptionally large and protruding eyes (present also in B. namaquensis); lack of a facial mask (present in B. fuscus, B. gibbosus, sometimes present in B. acutirostris), and locality; this species is confined to a rather narrow coastal strip in northwest Namaqualand (Du Preez and Carruthers 2009).
Description: Breviceps macrops is a short and stout frog, with a body length ranging from 4 mm to 6 mm (Boulenger 1907). It is a specialized burrower, with a spherical body and paddle-like feet (Channing and Wahlberg 2011). The venter has a transparent vascular window in the central and posterior regions of the abdomen. The tympanum is not visible in this species (Boulenger 1907). Eyes are strikingly large and prominent in this small frog (Boulenger 1907). Subarticular tubercles on the hand are absent or weakly developed; if present they are always single (Channing 2001). The extremely short limbs make it impossible for this frog to hop, although it can walk (Boulenger 1907). The coloration of this frog is predominantly yellow and brown, closely matching that of its habitat (Boulenger 1907). The dorsal surface bears smooth warts (Boulenger 1907). Dorsal markings are unique to individual frogs and identification of individuals can be made by photographs (Channing and Wahlberg 2011), although Channing (2001) also reports that the dorsal pattern is usually concealed by a layer of sand adhering to the skin. Males have a deeply wrinkled gular region (Du Preez and Carruthers 2009).
This frog has extensive webbing on its feet, in contrast to other members of the genus Breviceps. Carruthers and Passmore (1978) conjecture that the foot webbing enables traction on loose sand, as the frog moves about on the surface of its sand dune habitat at night (based on its distinctive tracks).
Etymology: The generic name Breviceps comes from the Latin words brevis, meaning "short," and ceps, meaning "head." The specific epithet macrops is derived from the Greek words macro, meaning "large," and ops, meaning "eye." Thus, Breviceps macrops means "short-headed large-eyed frog." The Afrikaans name Melkpadda ("milk frog") refers to the pale color of the dorsum (Channing 2001).