Brookesia ambreensis
Brookesia dwarf chameleons, endemic to Madagascar, were surveyed at the following localities in northern Madagascar (north of 16”s): Montagne d’Ambre, Ankarana, Manongarivo, Tsaratanana, Marojejy and Masoala. A total of 15 species occur in this region. Six new species are described and five new synonyms are identified. The genus Brookesia, the most speciose chamaeleontid genus in Madagascar, contains 23 species.
Almost all the northern Brookesia species are restricted to rainforest and occupy a relatively narrow elevational range. Although the northern rainforests represent just one-third of the total rainforest and about 5 % of the total island area, 65% of the Brookesia species occur in this region, and 52% are endemic t o the northern rainforest. Five new biogeographic regions of the northern rainforest are identified based on centres of Brookesia endemicity: Montagne d’Ambre, Northwest, Tsaratanana, Northeast and East. Speciation is thought to have been facilitated in the north through geographic isolation, with the Tsaratanana mountain range and the dry forests south of Montagne d’Ambre forming barriers to dispersal, and the Tsaratanana mountains acting as a centre of isolation. The fragmented distribution of several Brookesia species of low altitude rainforest suggests a period in Madagascar’s history when the climate was wetter and low altitude rainforest much more widespread.
Brookesia ambreensis sp. nov.
Holotype- UMMZ 203635, mature male, collected 8 January 1992, Antomboka River, Montagne D’Ambre National Park, 12’29’5 49” lO’E, 670 m altitude, Antsiranana Fivondronana, Antsiranana (Diego Suarez) Province, Madagascar, by J.B. Ramanamanjato, A. Raselimanana and C.J. Raxworthy.
Etymology- The specific name refers to the type locality Montagne d’Ambre.
Habitat and distribution.- All specimens collected in primary rainforest. All known specimens were collected between 650 and 1150m altitude a t Montagne d’Ambre, within the National Park and Parcel 2 of the Special Reserve. This species is probably endemic to Montagne d’Ambre.
Brookesia antakarana sp. nov.
Holotype- UMMZ 200071, mature male, collected 6 December 1991, Antomboka River, Montagne d’Ambre National Park, 12’32’S, 49’10’E, 1050 m altitude, Antsiranana Fivondronana, Antsiranana (Diego Suarez) Province, Madagascar, by J.B. Ramanamanjato, A. Raselimanana and C.J. Raxworthy.
Etymology- The specific name refers to the Antakarana people and region of northern Madagascar, where this species appears to be restricted.
Habitat and distribution- All known specimens were collected in rainforest between 50-1200 m altitude at Montagne d'Ambre, within the National Park and from Parcel 2 of the Special Reserve. This species is probably endemic to Montagne d'Ambre.
Brookesia bekolosy sp. nov.
Holotype- UMMZ 200078, mature male, collected 8 March 1992, Bekolosy, Manongarivo Special Reserve, 14"03'S, 48" 1 S'E, 1200 m altitude, Ambanja Fivondronana, Antsiranana (Dikgo Suarez) Province, Madagascar, by C.J. Raxworthy.
Etymology- The specific name refers to the type locality, the Bekolosy Plateau at Manongarivo.
Habitat and distribution- The holotype was collected at 22:00 h, roosting on a thin branch at 1 m height, in primary rainforest at 1200m altitude on a ridge. No other locality is presently known for this species. The rainforest a t Berkolosy is high altitude, with the forest canopy typically between 5-10m in height, and tree branches heavily draped with lichens. A more intensive survey was made by us at lower elevation forests in the Manongarivo Reserve (between 50-800m). The absence of this species a t these lower altitudes makes us think it is restricted to higher elevation forest, probably in excess of 1000m. This species is probably restricted to rainforest in the Northwest biogeographic region (see below).
Brookesia brygooi sp. nov .
Holotype- MHNP 8219, female, collected at Analavelona, Southwest Madagascar by H. Humbert.
Etymology- The specific name honours Dr E. R. Brygoo, who first described specimens of this new species, and contributed to the understanding of Brookesia systematics.
Habitat and distribution- In addition to the localities given for the holotype, paratype and other specimens, Brygoo (1 978) reported specimens (without calalogue numbers) from Bemaraha (Rtserve Naturelle IntCgrale No. 11) and Antsalova, also in the Southwest, Brookesia brygooi is found in the arid Southwest and West of Madagascar, occurring between 17-23"S, and is probably restricted t o native deciduous forests in these regions. Brookesia brygooi is one of the few arid-adapted species of the genus. The other species found in arid habitats of the Western Domain are B. bonsi, B. decaryi, B. perarmata and B. stumpfi.
Brookesia lineata sp. nov.
Holotype- UMMZ 200073, mature male, collected 8 March 1992, Bekolosy, Manongarivo Special Reserve, 14"03'S, 48" 18'E, 1200 m altitude, Ambanja Fivondronana, Antsiranana (Diego Suarez) Province, Madagascar, by A. Raselimanana.
Etymology- The specific name refers t o the unusual dark lines on the body of this species.
Habitat and distribution- The holotype was collected a t night, roosting on a leaf a t 1 m height, in primary rainforest a t 1200 m altitude on a ridge. No other locality is presently known for this species. For additional information see comments on habitat for Brookesia bekolosy.
Remarks- Brookesia lineata is unusual in that the flanks are marked by bold, dark brown, longitudinal lines. Brygoo (1978) does not describe such a coloration pattern for any other Brookesia species, although dark flank lines occur in male Brookesia thieli (UMMZ 196217-8).
Brookesia lolontany sp. nov.
Holotype- UMMZ 203629, mature female, collected 29 March 1993, Matsabory Lake, Tsaratanana, 14"09/S, 48"58/E, 2050 m altitude, Bealanana Fivondronana, Mahajanga Province, Madagascar, by Angeluc Razafimanantsoa.
Etymology- The specific name “lolontany” is the Malagasy name of the Tsaratanana mountain spirits that are believed to occupy the forests where the types were collected.
Habitat and distribution- UMMZ 203629 collected at 20:00h, roosting on a leaf at 0.7m height, in bamboo dominated primary rainforest; UMMZ 203630 collected at 20:00 h, roosting on a branch a t 0.05m height, in primary rainforest. Both specimens were collected in the Tsaratanana mountain range, which includes the highest mountain in Madagascar, Maromokotro, at 2876m altitude. The holotype of Brookesia lolontany was collected at a higher altitude than any other Brookesia species. This species is probably restricted to high altitude rainforest in the Tsaratanana Mountains.
Remarks- The only other species known to occur at a similarly high elevation is Brookesia nasus, which has been collected up to 1650m altitude at Andringitra. The latter species is morphologically the most similar species to Brookesia lolontany.
