A NEW SPECIES OF MICROGALE 



Table 4 Variation between populations of adult Microgale drouhardi. Dimensions given as range, mean±standard deviation and number of specimens in 

 parentheses. 





PN Montagne d'Ambre 



Bekolosy 



RS d'Ambatovaky 



RNI Zahamena 



Didy 



PN Mantady 





1000- 1250m 



1150m 



360-600m 



420-1 180m 





1100-1 150m 



Head and body length 



64-83 



73.0. 73.3 



62.5-74.4 



63.0-76.8 



80.1 



69.8-75.4 





75.8±5.39 





68.8±4.00 



69.7±3.78 





72.5+1.98 





(16) 



(2) 



(7) 



(17) 



(1) 



(4) 



Tail length 



67-83 



70.5, 72.4 



52.9-62.3 



52.7-62.1 



- 



63.7-71.0 





74.7±4.85 





56.7±3.24 



58.3±2.83 





67.7±2.66 





(16) 



(2) 



(7) 



(16) 





(4) 



Hind foot 



16-19 



17 



13-15 



14-15 



- 



16-18 



length 



17.6±0.77 





14.1 ±0.64 



14.6±0.49 





17.0+0.71 





(17) 



(2) 



(7) 



(17) 





(4) 



Ratio of tail length to 



0.8-1.2 



1.0 



0.8-0.9 



0.8-0.9 



- 



0.9-1.0 



head and body length 



1.0+0. 10 





0.8±0.05 



0.9±0.05 





0.9±0.04 





(16) 



(2) 



(7) 



(15) 





(4) 



Condyloincisive length 



22.5-23.9 

 23.3±0.45 



22.0, 22.5 



21.0-21.6 

 21.3+0.22 



20.5-22.3 

 21.4±0.45 



22.3 



22.4. 22.5 





(18) 



(2) 



(7) 



(17) 



(1) 



(2) 



Upper toothrow length 



10.6-11.5 



10.3, 10.7 



9.8-10.3 



9.7-10.4 



10.2 



9.9-10.5 





11.1 ±0.21 





10.1+0. 16 



10.0±0.23 





10.2±0.26 





(19) 



(2, 



(7) 



(17) 



(1) 



(4) 



Maxillary breadth from 



6.0-6.7 



6.2 



6.1-6.3 



5.9-6.4 



6.2 



6.3-6.9 



M3-M3 



6.4±0.14 





6.2±0.09 



6. 1+0. 17 





6.6±0. 1 1 





(19) 



(2) 



(7) 



(17) 



(1) 



(4) 



Braincase breadth 



9.0-9.7 



9.5.9.8 



8.5-9.1 



8.5-9.2 



9.2 



8.9-9.5 





9.4±0.18 





8.8±0.20 



8.9±0.20 





9.3±0.26 





(19) 



(2) 



(7) 



(17) 



(1) 



(3) 



Ratio of tail length tp 



3.0-3.6 



3.1.3.3 



2.4-2.9 



2.6-2.9 



_ 



3.0 



condyloincisive length 



3.2+0.21 





2.7+0.17 



2.7+0.12 









(15) 



(2) 



(7) 



(15) 





(2) 



age, and M. brevicaudata Grandidier, 1899 are exceptions [for 

 discussion of these apparently anomalous drier habitats see MacPhee, 

 1987]) it is conjectured here that rain forest is also the most likely 

 source habitat for the type series of M. drouhardi. Additionally the 

 large size of these specimens suggests that they may have originated 

 from a high altitude locality (see section on variation), which is most 

 compatible with Montagne d'Ambre rather than any of the other 

 localities listed above. 



In the original description, Grandidier described the dorsal pelage 

 as uniformly dark with the venter barely lighter in colour. The young 

 specimen mentioned in the type description (evidently an infant) is 

 described as having a black line along the mid-dorsum, which 

 according to Grandidier, disappears in adults. Re-examination of the 

 type series (by CR) shows that due to the discoloring and deleterious 

 effect of long-term storage in alcohol, these specimens are no longer 

 dark in colour but are now a dull reddish brown. Furthermore, a dark 

 dorsal stripe is discernable, which is obvious in some specimens, 

 where it is most evident on the head and anterior part of the body, but 

 faint and difficult to see in others. Shared features such as the 

 presence of a dorsal stripe, size and relative proportions of the body 

 and cranium, and morphology of the deciduous and permanent 

 dentitions, between the type series of M. drouhardi and specimens 

 recently collected (particularly from Montagne d'Ambre), lead to 

 the conclusion that they are conspecific. 



Microgale melanorrhachis Morrison-Scott, 1948 was originally 

 distinguished by the presence of its dark mid-dorsal stripe. The 

 description was based on the skin and skull of the juvenile holotype 

 (believed to be adult by the author) from Perinet [Andasibe], plus a 

 damaged skin from another locality (Ivohibe). Following the origi- 

 nal description, an additional specimen was recorded by Eisenberg 

 & Gould (1970) from Didy, east of Lake Alaotra and references to 



the species were included in the literature (Heim de Balsac, 1972; 

 Genest & Petter, 1975). MacPhee (1987), however, observed that a 

 proportion of M. cowani also exhibited a variable tendency to a mid- 

 dorsal stripe, and he synonymised M. melanorrhachis with M. 

 cowani on the basis of its dentition. Subsequent authors disregarded 

 MacPhee's opinion and continued to treat M. melanorrhachis as a 

 distinct species (Nicoll & Langrand, 1989; Nicoll & Rathbun, 1990; 

 Raxworthy & Nussbaum, 1994; Stephenson, 1995). The conclusion 

 drawn from the current study comparing recently collected large 

 series of adult and juvenile specimens from the localities listed 

 above with the type series of M. drouhardi and M. melanorrhachis, 

 is that they are conspecific. 



Description. Medium sized (see Table 4), tail slightly shorter or 

 subequal to head and body length. Dorsal pelage dark brown, brown 

 or rufous brown with well demarcated, distinctly darker brown mid- 

 dorsal stripe, extending from crown of head to base of tail (see Fig. 

 2); hairs of dorsal pelage have light grey bases, red distally with 

 brown tips; hairs of mid-dorsal stripe dark brown for most of their 

 length, with grey bases, lacking red band; guard hairs also dark 

 brown with grey bases. Ventral pelage silvery buff, buff or rufous 

 buff, individual hairs having grey bases and buff or reddish buff tips; 

 transition between dorsal and ventral coloration moderately distinct. 

 Tail bicolored, dark brown above, buff or reddish buff below; tail 

 scales readily visible, scale hairs short, each overlapping c 2 scales 

 on basal third of tail. Hind feet dark brown on outer dorso-lateral and 

 ventral surface, reddish buff or buff on inner dorso-lateral surface. 

 Skull medium in size (see Table 4 and Fig. 6), with moderately 

 elongated and shallow but broad rostrum, nasals extend beyond 

 zygomatic plate into interorbital region; frontals slightly dorso- 

 lateral^ inflated; braincase moderately broad, short and shallow; 



