Dwarf boas

Abstract

26 p. : ill., map ; 24 cm.Includes bibliographical references (p. 24-26)."Relatively small members of the family Boidae known to attain maximum over-all dimensions of 760 mm., with short prehensile tails comprising 0.85 to 0.95 per cent of total length. Trunk and tail slightly compressed, head distinct from neck, spurs restricted to males. Diameter of eye greater than its distance from lip, pupil elliptical. Rostral either wider than high and separated from prefrontal by internasals, or nearly as high as wide and in contact with large, azygous prefrontal. Frontal smaller than prefrontal, bordered on each side by a preocular and a supraocular. Parietals vestigial or indistinguishable from dorsal scales. Two nasals; nostril invariably in anterior nasal. Loreal single; one preocular; two or three postoculars. From eight to 10 supralabials, two or three reaching eye, first two reaching postnasal. Tubercles present on all cephalic shields. Infralabials nine to 11, first pair in broad contact behind a moderately large mental, followed posteriorly by two or three pairs of chin shields. Dorsal scales smooth, except for minute tubercles; midbody scale rows from 19 to 25, with reductions to 17 or 15 at vent. Addition and suppression of scale rows occurring between third and eighth rows anteriorly, by loss of paravertebral rows toward base of tail. Ventrals ranging from 204 to 258; anal plate undivided, from 39 to 46 single subcaudals; tail terminating in blunt spine. Hemipenes relatively long, bilobed; plicae on basal portion, calyces lacking crenate edges on lobes; sulcus spermaticus bifurcating near base (?), each branch of sulcus extending through plicate portion and calyces to terminus of lobe. Premaxilla with an ascending process, without teeth. Maxillary teeth 12 to 15, those at anterior end of bone larger and stouter than those behind them, which are progressively shorter posteriorly; palatine, five to eight; pterygoid teeth, 11 to 15; teeth on dentary, 13 to 15"--P. 23-24