Nadzikambia nubila sp. nov.

Nadzikambia aff. baylissi – Bayliss et al. (2024: table SI 1)

Chiperone sylvan chameleon

Holotype.

PEM R 24249, adult female, collected by a stream on Mount Chiperone (–16.5070; 35.7258, 1045 m a. s. l.), Zambézia Province, Mozambique by W. Conradie, G. Bittencourt-Silva, S. Loader and K. A. Tolley on 7 April 2017.

Paratypes.

(4 specimens). PEM R 24245, adult female, collected by a stream on Mount Chiperone (–16.5072; 35.7258, 1017 m a. s. l.), Zambézia Province, Mozambique by W. Conradie, G. Bittencourt-Silva, S. Loader, and K. A. Tolley on 5 April 2017. PEM R 24250, gravid female, collected by a stream on Mount Chiperone (–16.5080; 35.7248, 1021 m a. s. l.), Zambézia Province, Mozambique by W. Conradie, G. Bittencourt-Silva, S. Loader and K. A. Tolley on 8 April 2017. NHMUK 2025.3277, gravid female, collected near a stream on Mount Chiperone (–16.5066; 35.7260, 1053 m a. s. l.), Zambézia Province, Mozambique by W. Conradie, G. Bittencourt-Silva, S. Loader and K. A. Tolley on 7 April 2017. NHMUK 2025.3278, adult female, collected by a stream on Mount Chiperone (–16.508; 35.7248, 1020 m a. s. l.), Zambézia Province, Mozambique by W. Conradie, G. Bittencourt-Silva, S. Loader and K. A. Tolley on 7 April 2017.

Etymology.

This species is named after the “ Ciperoni ” – the term used locally for the weather that brings heavy clouds and orographic rainfall to the area. The cloud sustains the mid-elevation wet forest on this mountain. The epithet ‘ nubila’ is derived from the Latin ‘ nubilus’ meaning “ cloudy, ” and is modified to the feminine form to agree with the feminine gender of the genus Nadzikambia.

Diagnosis.

The new species is assigned to the genus Nadzikambia based on several distinctive characteristics, including the absence of gular and ventral crests, a weakly developed dorsal crest, a low casque, and heterogeneous body scales that form rosettes of tubercles on the lower flanks (Tilbury et al. 2006). This assignment is further supported by monophyly observed in both mitochondrial and nuclear genes (Tilbury et al. 2006; Branch and Tolley 2010).

Due to the lack of males in the type series this species cannot be compared to the male holotypes of other species. The new species can be distinguished from other species of Nadzikambia by a combination of the following characters: higher average number upper labials (16.6 versus 15.2 in N. mlanjensis and 15.5 in N. franklinae sp. nov., similar to other species), and lower average number of lower labials (17.4 versus 18.1 in N. goodallae sp. nov., similar to other species).

Additionally, the new species occurs in allopatry from all congeneric species, with the closest geographical relative being N. mlanjensis (approx. 65 km away) and differs genetically from other Nadzikambia species by: 0.7–4.7 % 16 S, 1.7–12.7 % ND 2, and 4.7–11.5 % ND 4 uncorrected net p distances (Table 2).

Holotype description.

Adult female male (64.7 mm SVL + 78.0 TL = 142.7 mm total length). The specimen has a single ventral incision in the chest region for tissue sample extraction.

Head short (HL / SVL = 0.29) and narrow (HW = 8.6 mm), distance from tip of snout to the superior edge of the casque is twice the width of the head (HL / HW = 2.21). The casque is slightly elevated above the nape, elongated, and its posterior apex points backward to a rounded rim. The crown of the head is flattened both anteriorly and posteriorly. It is depressed centrally and laterally relative to the parietal crest. The dorsal surface bears flattened, smooth scales, except along the parietal crest itself, and these abut one another with a few smaller interspersed granules. The largest scales occur along the midline of the snout, adjacent to the parietal crest, and alongside the lateral and supraorbital crests. Six scales are present between the supraorbital crests at mid-orbit. A reduced parietal crest is present on the crown, composed of three moderately raised, enlarged, smooth scales that increase in size posteriorly. The crown is bordered on both sides by raised tubercles of the lateral and supraorbital crests and at the rear by the casque. The temporal crest is absent. The lateral crest consists of 8 / 9 (right / left) raised, irregular tubercular scales that arise from the mid-upper rim of the orbit and curve upward around the casque. The supraorbital crest extends from the lateral crest at the upper posterior rim of the orbit, continuing forward over the eye and onto the snout. It is composed of a series of 14 / 13 raised scales. The canthus rostralis not elevated to form any protrusions or ‘ horns’. Three to four rows of smaller scales separate the canthi from the upper labials on the snout. The orbit is separated from the upper labials by one to two rows of small granules. Scales around the eye are elongated, longer than wide, with nine scales above and 10 below the orbit.

The nostril is rhombic, posteriorly directed, and positioned midway between the tip of the snout and the front of the orbit. It is separated from the upper labials by three rows of granules, with the scales in direct contact with the nostril much smaller than the larger ones in contact with the upper labials. The nostril is also separated from the orbit by three rows of scales and from the supraorbital crest by two rows of scales. No enlarged rostral or mental scales are present. The upper labials (17 / 17) are sub-hexagonal and subequal in size, with the largest scales located from the snout to the posterior rim of the eye; scales at the rictus are smaller and more rounded. The lower labials (19 / 18) are similarly sub-hexagonal and subequal in size, with the largest scales extending from the snout to the posterior rim of the eye; scales at the rictus are also smaller and more rounded. Scales bordering the lower labials are irregularly shaped and subequal in size to the lower labials. Gular grooves are fine and inconspicuous. Gular scales are round and raised, with the smallest scales located centrally and increasing in size toward the lower labials. The dorsal crest is mostly absent, except for five slightly raised scales anteriorly. A ventral crest is absent.

Body scales are relatively homogeneous and flattened, abutting one another and forming rosettes on the lower flanks. No smaller granules between scales on the flanks. The smallest scales are located on the belly and are more conical in shape, while the largest, squarish scales are found along the flanks and the paravertebral zone. Scales on the limbs are homogeneous and rounded, with the largest scales located on the outer surfaces of the hindlimbs and forelimbs.

Soles of hindfeet and forefeet with closely fit smooth round scales. Scales above digits heterogenous, larger posteriorly getting smaller anteriorly. Scales under digits slightly larger than those on the soles and more elongated. The scales on the digits directly adjacent to the claws are enlarged, followed by a similarly sized scale that is occasionally split into two.

The tail is longer than the body (TL / SVL = 1.21), dorso-ventrally flattened, and tapering distally to a fine tip. The dorsal and lateral scales are squarish and larger than the more rounded ventral scales.

Colouration in life (Fig. 6 E). Green body with intricate brown blotches. The head is a pale greenish laterally, with light orange-brown labials. The scales on the crown of the head are red-brown. The eyes are surrounded by lighter, greenish-blue scales. The flanks of the body feature a mixture of green and orange-brown scales, transitioning into irregular darker brown patches. The limbs are green-brown, with a slightly paler tone along the ventral surfaces and inner surface of limbs. The chest region blueish-grey. The ventral surface is predominantly pale greenish-yellow, with a white mid-ventral line. The tail exhibits a gradient of green-brown tones, with faint banding patterns and a slight orange tinge near the base.

Colouration in preservation (Fig. 17). Dark purplish-black colouration across the whole body. The head is purplish-black. The gular region is dark purplish, with the inner scale skin appearing white. The ventral surface has a narrow, pale white line extending between the limbs. Inner surface of limbs lighter purple than outer surface, with white inner skin. Sole of feet white. The tail is dark purple.

Paratype variation.

Measurements for the type series of Nadzikambia nubila sp. nov. are presented in Table 8. All paratypes are adult females. The size of the females (including holotype) ranges from 59.6–64.7 (62.0) mm SVL and 71.2–78.0 (72.9) mm TL. The tail is longer than the body, with an SVL / TL ratio of 1.12–1.28 (1.19).

The general scalation of the paratypes are very similar to that of the holotype, differing only in minor details. The upper labials number 16–17 (16.6), while the lower labials range from 16–20 (17.8). The lateral crest consists of 9–12 scales (10.0), the supraorbital crest has 12–16 scales (14.4), and the dorsal crest includes 4–6 scales (5.2).

Colouration in life and preservative of the paratypes are in agreement with the holotype. Male colouration currently unknown.

Natural History.

Three of the females (PEM R 24250, NHMUK 2025.3277, NHMUK 2025.3278) collected in early April were gravid. Clutch sizes ranged from 4 to 5 eggs (4.3), with oviductal eggs measuring 12.9–14.1 (13.5 ± 0.4) mm in length and 6.4–7.1 (6.7 ± 0.3) mm in width.

Habitat.

All specimens were collected in an evergreen mid-elevation wet forest between 1017–1053 m a. s. l. They were found at night perched in tree branches at heights of 4–7 m above the ground but are likely to also occur higher in the canopy. The habitat consists of a closed-canopy forest reaching tens of meters high, with occasional small gaps in the canopy along stream gullies.

Distribution.

Occurs only in the mid-elevation wet forest of Mount Chiperone in northern Mozambique (Figs 1, 18).

Conservation.

Mount Chiperone is known to the local community as “ the cloud maker ” as the mountain catches atmospheric moisture, creating cloud cover and forming the rain that not only supplies the forest, but the surrounding landscape. The mountain is also considered holy to most of the communities surrounding it, which results in a measure of community protection in terms of over-exploitation. Rainforest originally occurred above ca. 1000 m elevation below which was Brachstegia woodland (savanna). Forest extent as of 2024 is about 7 km 2 from ca. 15 km 2 in 2006 (Fig. 18) for a 53 % decrease in forest cover. Most of the forest loss appears to be on the lower south-west slopes of the mountain and while some of this clearly shows the scars of agricultural use, other areas show only what appears to be attrition of forest on the edges, being replaced by scrubby vegetation (Fig. 18). Similarly, there appears to be a recent change in vegetation at the summit where Google Earth satellite imagery between 2006–2016 shows trees covering the summit, but beginning in 2018 and progressing to present, the area appears to be progressively devoid of vegetation, having shifted to what appears to be open granite patches. It is unclear if this change was due to slash and burn practices which seems unlikely at such high elevation, leaving the lower slopes unaffected. It is possible that orographic rainfall that would normally have provided the moisture needed to maintain forest has been reduced, and the forest extent is being impacted. Thus, while the mountain shows long-term impacts from agriculture along the lower slopes, the forest at higher elevations is nevertheless contracting, and this may be due to climatic changes.

The Area of Occupancy (AOO) mapped as the total summed area of the number of 2 x 2 km grid cells assumed to be occupied is 16 km 2 and EOO (the convex polygon surrounding both remaining forest patches but upscaled to match the AOO as per the IUCN guidelines) is estimated at 16 km 2.