Rhinolophus hipposiderus minutus Montagu.

Andersen, Knud, 1905, On some Bats of the Genus Rhinolophus, with Remarks on their Mutual Affinities, and Descriptions of Twenty-six new Forms., Proceedings of the Zoological Society of London 2, pp. 75-145 : 142-144

27 c. Rhinolophus hipposiderus minutus Montagu.

Vespertilio minutus Montagu, Trans. Linn. Soc . ixt (1808)

p. 162, pl. 18. figs. 7-8.

Diagnosis. Forearm 36 3-39 mm.

Details. English and Irish individuals of Rh. hipposiderus differ from the Central European form in being on an average (and nearly always also absolutely) smaller. The length of the forearm varies, in 30 adult specimens from England, Wales and Ireland, between 36 *3 and 39 mm., the average being 37 6. In other words: the average size of the British race is considerably belorv the minimum of the typical form, and almost eXactly like maXimum

c / Rh. h. minimus .

Distribution. England, Wales, Ireland §.

Technical name. Till the close of the 18th century, the two Bats now called Rh. ferrum-equinum and 7?/z. hipposiderus were regarded as a large and a small variety of one species. In 1808, Montagu pointed out some of their distinctive characters, and proposed for the smaller species the name Vespertilio minutus , being evidently unaware that the two Bats had already twice been specifically separated—by Bechstein in 1800, and by Hermann in 1804. Montagu’s name, as being antedated by “ hipposiderus ” was soon almost completely forgotten (it is not recorded in Dobson’s Catalogue). The original description of F. minutus being, however, based on English specimens, the name is now available for the British race of hipposiderus. Remarks. We are now able to form a much clearer idea of the past history of Rh. hipposiderus. It originated from a Bat allied to Rh. minor, somewhere in Asia, most probably near the western border of (if not within) what is now called the Oriental Region. From there it spread southwestwards into Africa, westwards through the Mediterranean countries to Central Europe and the British Islands. There is, to my knowledge, no record of Rh. hipposiderus from Egypt; if this is evidence that it does not occur, and has not occurred, there, it is at the same time a

proof that it did not reach Erythrea and Sennar from the Mediterranean, by way of the Nile Valley, but via the formerly existing, broad land-connection between S.W. Asia and N.E. Africa. The individuals which established themselves in Central Europe, N. of the Balkans ami the Alps, gradually making their way as far north as the Baltic, developed into a distinct, larger race {Rh. h. typicus). The British colony, originally the extreme western offshoot of the larger form, but soon cut off from communication with the Continental main stem, also developed into a distinct race {Rh. h. minutas); it got the not unusual stamp of an island form: the smaller size; and so it came to occupy, seemingly, but neither phylogenetically nor geographically, a somewhat intermediate position between the northern and southern races of hipposiderus, between its immediate and its more remote progenitors.

It is worth noticing that Rh. hipposiderus is distributed over the whole of England, occurring also in several places in Ireland, whereas Rh. ferrum-equinum is confined to the extreme south of England, apparently not farther north than Essex, Gloucester, and Pembroke, and has never reached Ireland. It may indicate that of these two comparatively recent immigrants into the British Islands, Rh. hipposiderus was the earlier comer. This assumption seems strengthened by another fact. On the Continent Rh. hiqyposiderus goes farther northwards and considerably higher up on the mountains than ferrum-equinum . It is but reasonable to suppose that the more hardy species was also the first to make its way to England.