Toxicodryas pulverulenta (FISCHER, 1856)
Can you confirm these amateur observations of Toxicodryas pulverulenta?
|Higher Taxa||Colubridae, Colubrinae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Common Names||E: Fischer's Cat Snake|
|Synonym||Dipsas pulverulenta FISCHER 1856: 11|
Dipsadomorphus pulverulentus — STERNFELD 1917
Dipsadomorphus Boueti CHABANAUD 1917: 373
Boiga pulverulenta — SCHMIDT 1923: 102
Boiga pulverulenta — MENZIES 1966
Toxicodryas pulverulenta — TRAPE & ROUX-ESTÈVE 1995: 40
Boiga pulverulenta — PITMAN 1974
Boiga pulverulenta — BROADLEY 1998
Toxicodryas pulverulenta — RÖDEL & MAHSBERG 2000
Boiga pulverulenta — HUGHES 2000
Toxicodryas pulverulenta — LEGRAND 2002
Boiga pulverulenta — BURGER et al. 2004
Toxicodryas pulverulenta — CHIRIO & LEBRETON 2007
Toxicodryas pulverulenta — ULLENBRUCH et al. 2010
Boiga pulverulenta — SEGNIAGBETO et al. 2012
Toxicodryas pulverulentus — WALLACH et al. 2014: 733
Toxicodryas pulverulentus — TRAPE & BALDÉ 2014
Boiga pulverulenta — CARLINO & PAUWELS 2015
Toxicodryas pulverulenta — SPAWLS et al. 2018: 512
Toxicodryas pulverulenta — GREENBAUM et al. 2021
|Distribution||Liberia, Sierra Leone, Guinea (Conakry), Ivory Coast, Ghana, Togo, Benin, Nigeria, Gabon, Cameroon, Central African Republic, Democratic Republic of the Congo (Zaire), Congo (Brazzaville), Uganda, Angola, Republic of South Sudan (RSS) ?|
Type locality: Edina, Grand Bassa County, Liberia (see comment)
|Types||Syntype: ZMH R04376 (formerly no. 339), Formerly there were 2 syntypes.|
|Diagnosis||Diagnosis. A species of Toxicodryas restricted to West Africa, west of the Niger Delta, defined by the following combination of characters: maximum SVL < 1 meter (vs. maximum SVL > 1 meter in T. blandingii and T. vexator sp. nov.), DSRN 19–21 (vs. 23–25 in T. blandingii and 23–29 in T. vexator sp. nov.), DSRM 19–21 (vs. 21–25 in T. blandingii and T. vexator sp. nov.); cloacal plate undivided (vs. usually divided in T. blandingii, and divided or undivided in T. vexator sp. nov.); both sexes brown to pink with darker cross-bars that often enclose a whitish spot, and the dorsum and venter sprinkled with fine dark brown or black spots (vs. adult males glossy or velvety black with a yellow venter, and adult females light brown, gray, or yellowish-brown with light-brown or cream cross-bars on the flanks, with yellowish-brown venters in T. blandingii and T. vexator sp. nov.); hemipenis relatively long with long spines mid-way along the shaft that decrease in size towards the apex and base, with a domed apex (vs. hemipenis relatively short and massive [i.e., broad], proximal third covered with spines, distal two-thirds dimpled with a flattened apex in T. blandingii and T. vexator sp. nov.) (GREENBAUM et al. 2021).|
Variation. Morphometric variation of Toxicodryas pulverulenta is shown in Table 2. Chabanaud (1917a) first noted that some individuals (including the type of Dipsadomorphus boueti) can have a few single subcaudals posterior to the cloacal plate. Bogert (1940) provided morphometric data, but he did not distinguish between populations from Liberia (T. pulverulenta) and former French Cameroon (T. adamanteus sp. nov.), except that “the Liberia specimens are distinctly more reddish brown than the Cameroon specimens.” However, he listed the maximum total length of a male (1112 mm) and female (1050 mm) T. pulverulenta from Liberia. In snakes from West Africa (without noting sex), including Cameroon where T. adamanteus sp. nov. occurs, Angel (1933:146) noted temporal formula variation of 2 + 2 (rarely 2 + 3 or 3 + 2 or 1 +2), 236–276 ventrals, 96–132 subcaudals, and a maximum size of 1225 mm; nearly identical data were reported by Villiers (1950a), Doucet (1963), Stucki-Stirn (1979), and Chippaux (2006). Although all of our examined specimens and most literature records noted the 3rd to 5th supralabial in contact with the eye (e.g., Villiers 1950b), Chippaux (2006) documented individuals with the 4th to 6th supralabial in contact with the eye, and sometimes, only two scales in contact with the eye, but some of these specimens might be attributable to T. adamanteus sp. nov. Segniagbeto et al. (2011) reported snakes from Togo with 165–175 ventrals, which is undoubtedly erroneous.
Fischer (1856:83) noted his type specimen had seven maxillary teeth that were oriented nearly backwards, becoming larger posteriorly. These were followed by two larger teeth (i.e., fangs) that were furrowed in a “besonderen Hauttasche” [special skin pocket]. There were 10–12 mandibular teeth, which were slightly curved towards the back of the mouth, and increased in size posteriorly. Bogert (1940:61) remarked “five specimens examined show variation from eleven to thirteen anterior subequal teeth followed after a very short diastema by two larger grooved fangs and a smaller fang, the total number of teeth being fourteen to eighteen.” Because only two of his examined specimens originated from former French Cameroon (attributable to T. adamanteus sp. nov.), at least three of these specimens were from Liberia, which are attributable to T. pulverulenta. In snakes from Ghana, Leeson (1950) noted 11–13 maxillary teeth, becoming slightly larger posteriorly, followed by 2 fangs, and sometimes a 3rd, smaller fang; 14–16 palatine and pterygoid teeth, and 15 mandibular teeth with the anteriormost ones largest. Johnsen (1962) reported that his specimen from Liberia had 11 maxillary teeth on one side, and six on the other. Based on a specimen from Liberia, Malnate (1972) noted the species lacks posterior hypapophyses.
In his original description of the species, Fischer (1856:83) described the coloration in great detail as chocolate brown above, yellow below, finely dotted everywhere. On each side, near the back, there was a large number (60– 70) of pale red spots that lacked dark edging and extended over 4–6 scales. Usually the spots on one side alternated with those on the other; sometimes they also were opposite to each other and in this case were connected to weak “Querbinden” [cross-ties] by bright red connecting strips that extended over the back. Usually there was a small black spot under each of these spots on the outermost tip of the corresponding ventral shields. The innumerable fine black points, with which the whole body was sown, were grouped on the abdominal shields on each side at the point where they bent over to rise sideways, to form a black spot, which in their succession looked like a black longitudinal band, whereby the narrow belly appeared delimited from the flanks. Head was brown and without black lines. Upper lip, lower lip, throat yellow, dotted with black. Günther (1858:173) described the dorsum of two Nigerian specimens as “brown with a strong cast of purple” with elliptical transverse streaks, and at mid-body, these streaks had a small yellow spot in their center. In his description of Dipsadomorphus boueti, Chabanaud (1917a) noted the types were light brownish gray and dotted with brown, whereas the supralabials and venter were yellowish gray.
Leeson (1950) described animals from Ghana as brownish red on the dorsum, with “dull brown” heads, and “lightly coloured” patches on the flanks that had a black edge on the lower margins. There were more narrow light gray bands on the anterior third of the body that gradually diminished to form light gray patches on the posterior two-thirds of the body. The ventral surface of the head was white or cream, whereas the venter of the body was pinkish with numerous brown spots. Brown lines “commence”[ed] just before the middle of the body on each side of the ventrals, and continued along the edge of the ventrals to the tip of the tail. In his description of two specimens from Ivory Coast, Villiers (1950b) noted their color pattern was pale brownish gray, the dorsal scales dotted with black, the back with alternate dark brown diamond spots (some ocellated with white). yellowish ventral surface with two black lateral lines. Doucet (1963) noted the dorsal coloration ranged from uniform reddish or yellowish or powdery brown, sometimes with dark bars, with ventral coloration ranging from yellowish to pinkish. Chippaux (2006) noted dorsal coloration as dark beige or reddish with occasional dark gray designs or crossbars; venter pinkish with two dark lateral lines. Based on photographs of an adult male from Guinea (Fig. 11B), the base of the tongue is orangish red, and the forked tip is silvery white with black edging. Our observations of live specimens suggest the dorsal scales have an almost satiny sheen, similar to the appearance of a spider web (MOR, pers. obs.) (GREENBAUM et al. 2021).
|Comment||Distribution: Has been reported from Sao Tome but records neen confirmation (SCHÄTTI & LOUMONT 1992); recent investigations show it actually doesn’t occur there (Ceríaco et al. 2018). The type locality has also been given as Sao Tomé [Is., West Africa], but that appears to be incorrect (Greenbaum et al. 2021,Loveridge 1958: 269).|
Habitat: fully arboreal (Harrington et al. 2018).