Cryptophis

Abstract: The Hooded Snakes, variously placed in Denisonia, Unechis, Parasuta or Cryptophis, are herein treated as a species-group within the large genus Denisonia Krefft. In Western Australia this species-group is represented by Denisonia nigriceps (Giinther), D. monachus Storr, D. gouldii (Gray) and D. spectabilis (Krefft). The western representative of D. spectabilis is described as a new subspecies D. s. nul/arbor. D. s. spectabilis of South Australia is redescribed.

Abstract: Until now the Elapid genus Denisonia had not been recorded from New Guinea, and this is remarkable in so far as the genus is known from Australia (and Tasmania) to the south, and from the Solomon Islands to the northeast of New Guinea. It is therefore not very surprising that now evidence has been procured of the presence of the genus in New Guinea. A single specimen of a species that we believe to be new to science was collected at Merauke in southern West New Guinea by Mr. A. J. M. Monsanto in 1959. The genus Denisonia is here accepted in its old sense, such as it was used by Boulenger (1896, p. 332), and by the majority of subsequent authors. Recently, Worrell (1961a; 1961b, pp. 24-26; 1963) has made attempts to divide Denisonia into eight genera, but as yet the new genera diagnosed by him do not seem to be well founded. In his key to seven of the genera distinguished by him at that time, Worrell (1961b, p. 25) uses inter alia the character "preocular and prefrontal scales in contact" as opposed to "preocular and prefrontal scales not in contact". However, in all species concerned the preocular is in contact with the prefrontal. Probably Worrell meant to indicate that in one of the genera described by him (Unechis) the prefrontal borders the preocular not only above, but also anteriorly, thus reaching the labials, and separating the nasal from the preocular; in other genera described by Worrell (1961b: Cryptophis, Drysdalia, Parasuta, and also in Suta and Denisonia Krefft) the preocular is in contact with the nasal, separating the prefrontal from the labials. However, it may be pointed out that this character is subject to individual variations. Thus, Boulenger (1896, p. 345) already stated that in Denisonia pallidiceps (Gunther), the type

Abstract: The two Cryptophis species are moderate-sized (up to 1 m length) nocturnal ven- omous snakes of northern and eastern Australia. Examination of 600 museum specimens provided data on body sizes, sexual size dimorphism, reproductive cycles and food habits. Males attain larger body sizes than females in C. nigrescens, but not in C. pallidiceps. Both species are viviparous, with a mean litter size of four. Parturition occurs in late summer (Feb.-Mar.) in southern populations, but may be earlier in snakes from tropical areas. Relative clutch mass averaged 60% in captive C. nigrescens, and offspring averaged 152 mm SVL and 2.3 g mass at birth. Male combat was recorded in C. nigrescens. Both Cryptophis species feed on reptiles, especially scincid lizards (89% of all prey items found). A wide range of skinks is taken, but most are diurnally-active forms. Like many other Australian elapids, Cryptophis forage nocturnally for sleeping skinks. The absence of frogs from the diets of such elapids is a consistent but puzzling phemonenon. Relative eye size in Cryptophis is similar to that in other nocturnal elapids. The proteroglyphous snakes of Aus- tralia are best-known for their highly toxic venoms; several of the large elap- ids are more deadly to man than are any snakes from other continents (Broad et al., 1979). However, these large and spectacular species constitute only a mi- nor part of the radiation of the Elapidae in Australia. Most elapids are small and secretive; although they may be abun- dant, they have attracted little popular or scientific attention. The present study