Psammophis zambiensis, Hughes & Wade, 2002

Trape, Jean-François, Crochet, Pierre-André, Broadley, Donald G., Sourouille, Patricia, Mané, Youssouph, Burger, Marius, Böhme, Wolfgang, Saleh, Mostafa, Karan, Anna, Lanza, Benedetto & Mediannikov, Oleg, 2019, On the Psammophis sibilans group (Serpentes, Lamprophiidae, Psammophiinae) north of 12 ° S, with the description of a new species from West Africa, Bonn zoological Bulletin 68 (1), pp. 61-91 : 75-84

PSAMMOPHIS ZAMBIENSIS Hughes & Wade, 2002

Zambian Whip Snake, Psammophis zambien, Sambische Sandrennnatter

Psammophis sibilans (not Linnaeus) Pitman, 1934: 297 (part, ‘Chimikombe’ specimens only).

Dromophis lineatus (not Dumèril & Bibron) Laurent, 1956: 247 (Kundelungu, DRC).

Psammophis? sibilans Broadley & Pitman, 1960: 445 .

Psammophis brevirostris leopardinus (not Bocage) Broadley, 1971: 88; Brandstätter, 1955: 53, Pl. 39 & 1966: 48 ( Zambia only); Haagner et al., 2000: 16.

Psammophis zambiensis Hughes & Wade, 2002: 75 . Type locality: “Abercorn”, probably = Mweru-Wantipa, Zambia. Holotype: BM 1959.1.1.81; Broadley et al., 2003: 170.

Description. (23 specimens examined) Nostril pierced between 2 nasals; preocular 1, separated from frontal; postoculars 2; temporals usually 2+2/3; supralabials 8 (rarely 7 or 9), the 4 th & 5 th (rarely 3 rd & 4 th) entering orbit; infralabials 9 or 10, the first 4 in contact with ante- rior sublinguals; dorsal scales in 17-17-13 rows; ventrals 147–161; cloacal divided (entire in NMZB 16601); subcaudals 72–83. Brandstätter (1995, fig. 39) has published

Psammophis sibilans group 77 a SEM micrograph of a dorsal scale of NMZB 10636 from Ikelenge, Zambia.

Dorsum greenish-brown, top of head with complex pale markings; labials yellowish speckled with black; a pale double chain marking covers the dorsal nine scale rows anteriorly, dorsal scales heavily edged in black (more extensive in juveniles and subadults), a pale dorsolateral stripe on scale row 4 and 5 continues caudad; lower half of outer scale row and ventrals greenish, free edges of ventral irregularly bordered with black (more extensive in subadults). Two specimens from Sakeji School ( Haagner et al. 2000), and all those from the Muchinga escarpment and Malawi, lack the distinctive dorsal and ventral markings, but are still distinguishable from sympatric / parapatric P. mossambicus by their low ventral and subcaudal counts .

Size. Largest male (PEM 6237 – Sakeji School, Zambia) 770 + 275 = 1,045 mm; largest female (PEM 6224 – Sakeji School, Zambia) 740 + 180+ mm (tail truncated).

Remarks. This taxon was originally assigned to P. leopardinus , which it resembles in dorsal colour pattern, but it differs in its much lower mandibular tooth counts and also lower ventral and subcaudal counts. In addition there seems to be no connection across eastern Angola and the two forms occupy very different habitats. The sequences of “ P. occidentalis ” from Zambia and Burundi in Kelly et al. (2008) and Fig. 1 may correspond to this species. See Hughes & Wade (2002) for further data.

Habitat. Apparently inhabiting swampy areas in moist miombo woodland in Zambia and Katanga or montane grassland in Malawi.

Distribution. Northern Zambia and adjacent Katanga Province of the DRC, extending into montane areas of northern and central Malawi.

TENTATIVE KEY TO THE SPECIES OF PSAMMOPHIS NORTH OF LATITUDE 12°S (excluding the cryptic species only known by their sequences)

1a. Dorsal scales in 17 or 19 rows at midbody .............. 2

1b. Dorsal scales in less than 17 rows at midbody ...... 14

2a. Supralabials usually 8 (occasionally 9 for P. sibilans ), with fourth and fifth, or four, fifth and sixth entering the orbit (occasionally fifth and sixth for P. sibilans ). Dorsal scales in 17 rows.......................................... 3

2b. Supralabials usually 9, with fifth and sixth, or four, fifth and sixth entering the orbit. Dorsal scales in 17 row (rarely 19........................................................ 10

3a. Temporals 1+2, rarely two anterior temporals. Ventrals 138–167, subcaudals 73–107. Dorsum brown or olive, uniform or with a fine yellow vertebral line and a yellow dorsolateral stripe. Belly yellowish, often with short transverse black marks at the outer edges ........................ Psammophis lineatus

3b. Temporals basically 2+2, fusions and/or divisions frequent ................................................................... 4

4a. Usually the first five infralabials in contact with the anterior sublinguals ................................................. 5

4b. Usually the first four infralabials in contact with the anterior sublinguals ................................................. 6

5a. Subcaudals 71–102, ventrals 160–184. Dorsum brown, often with a black and white vertebral chain, the black pigment either covering the edges or the hindermost part of the scale. A pale dorsolateral stripe absent or present. Top of head often with a pale median stripe on the snout which forks when reaching the frontal and then borders the frontal. Sahel and Sudan savanna from Cameroon to Ethiopia and Tanzania............................. Psammophis rukwae

5b. Subcaudals 98–119, ventrals 154–178. Dorsum uniform or strongly stripped with a black and white vertebral chain, the black pigment covering the edges of the scale, and a pale dorsolateral stripe. Top of head often with a pale median stripe on the snout which is interrupted before the frontal or forks only after the middle of the frontal. Northeastern Africa from Egypt and Sudan to Ethiopia............................ ................................................. Psammophis sibilans

5c. Subcaudals 96–120, ventrals 156–185. Dorsum brown with a black and white vertebral chain, the black pigment covering the hindermost part of the scale. A pale dorsolateral stripe absent or present. Top of head often with a pale median stripe on the snout which forks when reaching the frontal and then borders the frontal. Sahel, Sudan and Guinean savannas of West Africa............................................ ......................... Psammophis afroccidentalis sp. nov.

6a. Cloaqual scale usually entire. Dorsum and top of head usually uniform. If present, reticulations on the top of the head may form a complex network, but never with a pale median stripe on the snout which forks and then borders the frontal. Moist savannas of West Africa .............................. Psammophis phillipsi

6b. Cloaqual scale divided............................................. 7

7a. Ventrum yellowich usually with a pair of well-defined black lines................................................................ 8

7b. Ventrum uniform or with ill-defined black lines or dashes ...................................................................... 9

8a. Top of head with a yellow median stripe on the snout and the frontal. A yellow vertebral line bordered by two pairs of brown and one pair of yellow dorsolateral stripes. Ventrals 148–180, subcaudals 90–129. Dry savannas of West, Central and East Africa................ ............................................ Psammophis sudanensis

8b. No median stripe on the top of the head. Dorsum brown uniform. Ventrals 148–170, subcaudals 95– 117. Coastal areas of East Africa .............................. .............................................. Psammophis orientalis Psammophis sibilans group 79

9a. Subcaudals 84–122, ventrals 154–188. Dorsum olive to yellow-brown, uniform or with black-edged scales forming narrow black longitudinal lines, or with scattered black scales (rarely largely black), or with a black and white vertebral line and a pale dorsolateral stripe. Top of head uniform or with complex pale markings. Ventrum yellow or whitish, uniform or with rows of black lateral spots or irregular black spekling, some specimens with a mid-ventral band of grey obfuscation. Moist savannas and forest clearings from southeastern Nigeria to eastern and southern Africa ............... Psammophis mossambicus

9b. Subcaudals 75–90, ventrals 148–165. Dorsum greenish-brown with scales often heavily edged in black and the nine median rows with black and white markings. Top of head reticulated. Free edges of ventrals irregularly edged in black. Zambia, Malawi and southern Democratic Republic of Congo........... Psammophis zambiensis

9c. Subcaudals 79–106, ventrals 151–167. Colour pattern variable, a pale dorsal chain pattern usually changes posteriorly to paired dorsolateral stripes. Pale transverse and reticulated markings often present on back of head. Chin and throat speckled and sometimes bands of grey flecking on ventrum. Angola and northern Namibia................................... ........................................... Psammophis leopardinus

80 Jean-François Trape et al.

10a. Subcaudals more than 140 ................................... 11 10b. Subcaudales less than 135 ................................... 12

11a. Ventrals 170–198, subcaudals 143–178. Flanks and belly heavily speckled with black. Semi-desert and arid savannas from southeastern Egypt to Somalia and northern Tanzania....... Psammophis punctulatus

11b. Ventrals 186–211, subcaudals 142–172. Flanks not speckled with black, belly with a large median grey band. Sahel and sudano-guinean savannas from Senegal to Chad and Central African Republic......... .................................................. Psammophis elegans

12a. Usually three supralabials entering the orbit. Ventrals 155–181, subcaudals 106–132. Angola and southern Africa................. Psammophis subtaeniatus

12b. Usually two supralabials entering the orbit. North Africa and Sahel .................................................... 13

13a. Ventrals 167–181. Dorsal scales in 17 rows at midbody........................................ Psammophis schokari

13b. Ventrals 183–203. Dorsal scales in 17 or 19 rows at mid-body .............................. Psammophis aegyptius

14a. Dorsal scales in 11 rows at mid-body ...................... ............................................. Psammophis angolensis

14b. Dorsal scales in 13 rows at mid-body...................... .................................................. Psammophis pulcher

14c. Dorsal scales in 15 rows at mid-body .................. 15

15a. Two upper labials, usually fourth and fifth, entering orbit. Ventrals 161–191, subcaudals 107–133. Top of head with transverse black bars. West and Central Africa................................ Psammophis praeornatus

15b. Two upper labials, usually fifth and sixth, entering orbit. Ventrals 138–156, subcaudals 102–134. Top of head more or less uniform. East Africa ..................... .............................................. Psammophis biseriatus

15c. Three upper labials, usually the fourth, fifth and sixth, entering orbit. Ventrals 142–169, subcaudals 81–123. Top of head with dark bordered tan blotches and a light longitudinal stripe along the junctions of infranasals and prefrontals. East Africa .................... ............................................ Psammophis tanganicus

82 Jean-François Trape et al.

84 Jean-François Trape et al.

Acknowledgments. Part of this work was based on an unpublished 2005 preliminary manuscript by D. G. Broadley, C. Kelly, B. Lanza and J.-F. Trape which included only morphological data, most of them from the databases of DGB and JFT, and further data communicated to DGB by B. Hughes and B. Lanza. This manuscript has never been published due to numerous remaining issues that were only resolved recently, at least in part, when molecular data become available for specimens from Egypt, and central, eastern and western Africa. Christopher Kelly published separately his molecular study of eastern and southern African specimens ( Kelly et al. 2008). Donald G. Broadley and B. Lanza unfortunately deceased before the achievement of this work, and we aknowledge here their enormous contribution both to this study and African herpetology. We thank L. Chirio for providing samples of P. mossambicus from Gabon, A.-G. Zassi-Boulou for helping collecting samples of P. mossambicus in the Republic of Congo, P. Geniez for useful discussions on the Psammophis species of northern Africa, and P. Wagner and B. Hughes for helpful remarks on a preliminary manuscript.

Figures

Fig. 1. Phylogenetic tree (16S, Cyt. B, ND4) of the African species of Psammophis inferred with maximum likelihood from a concatenated dataset. Numbers on branches are bootstrap support values. Black lines separate the major lineages, and red lines clades within lineages 1–3 which include most species of the Psammophis sibilans group.