Geographical Variation in Palm Swifts Cypsiurus.Pdf
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obliged to Dr. G. F. Mees of the Rijksmuseum voor Natuurlijke His toric in Leiden for the loan of material andaddition for permissionto the curatorstofrom andselect museumsthe listed in BrookeAmericanbased was(1971a), done I Museumamwhile holdingrecognisedof a Frankis Natural supported.M. ChapmanMuseum, History,memorialMuch ofgrantNew the York.work on In which this paper is Cypsiurus review of infraspecific variation has been made since 1892 when Hartert’s work appeared in thealmost universally accepted throughoutThis paper this examinescentury. the speciesNo andoverall races proposed in the genus VOL. IX, PART 15 ISSUED 1ST SEPTEMBER 1972 3 Vovitates DURBAN MUSEUM (Dept, of Zoology, University of Rhodesia, Salisbury, Rhodesia) ) . 2 1 0 2 GEOGRAPHICAL VARIATION IN PALM SWIFTS vol. 16. Two new races are proposed and one not usually d Lesson, 1843, in the Apodidae. The genus itself has been e t a d ( ISSUED BY THE DURBAN MUSEUM, DURBAN, SOUTH AFRICA r e h s i l b u (. P AVES: APODIDAE) e INTRODUCTION CYPSIURUS CYPSIURUS SPP. R. K. BROOKE h t y b d e t by n Catalogue o f Birds in the British a r g e c n e c i l r e d n u y a w e t a G t e n i b a S y b d e c u d o r p e R length of less than 1 cm; tail-fork less than C.batasiensis unemarginate and rounded as in the juvenal plumage nor highly ta-length c. 3 cm), as well as beingmarkedly emarginate;species. tail-fork in ther comment. InLichtenstein, point of1823, andfact, adequate discussionAfrican Palmvirtually Swift all workers have lumped sider cies. sub-adult plumage. There are no intermediates between thesefifth rectricesspe which are not particularly emarginate and withemarginate a delta- as in the adult, and whosebe delta-lengthrecognised is by 1,5-2,0the shapecm. mostof feathersthe and particularlyfifth adultsrectrix, thosemore ofthan the which 5 wing,cm deep;tail is and a underdistinctiveneither tail- juvenalthe fifth plumage(outermost) in retriceswhichgreatly elongated beyond the numberfourth (del of significant characters and should be treated as separate mens of this genus by saying “in my opinion we sheltered nook on withthe salivaoutside and placedof a onThe man-made a palmnest frond,is madestructure. a oftunnel feathers in thatch, and vegetableor a high down cemented togethersmall size, dull plumage, toes placed forward in opposed pairs with The genus a vertical wall with a lip at the bottom to which the eggs are glued. numbers (Brooke and 1963, has 1971a).thus itrecently also breeds expandedon man-made itsstructures range such as inbridges detailand buildingsand its total held closed. - distance between the fourth and fifth rectrices when the tail is mage in which the feathers have dull white tips; no recognizable coverts are tipped with dull buffy; a sub-adult plumage which can Eastern Ghats of India, end up their brief discussion of their speci a reduced number of phalanges (2, 3, 3, 3), and nest in the shape of mon in areas which tropicalcontain Asiatall as farpalm as Javatrees. andParticularly the Philippines in Africa,and is usually com a type from the material 218lent. As usual, delta-length means the ) . 2 Whistler & Kinnear (1935), in discussing a collection from the 1 0 2 C.gracilis batassiensis d Geographical Variation in Palm Swifts Cypsiurus Spp. e C.parvus t a d Cypsiurus ( in tropical Asia has an unstreaked throat in the adult; r e h (Sharpe), 1871: Madagascar, differs from s SPECIES WITHIN THE GENUS i in tropical Africa has in the adult a streaked throat; l and b u Cypsiurusparvus P is distributed throughout tropical Africa and e h t infumatus batasiensis y b d e t n a r Cypsiurus g parvus as races of the widely spread J. E. Gray, 1829, without fur e c ” . On the strength of this hardly n e c i l and r e 4 is characterised by its d cm deep; a juvenal plu n u batasiensis y a (sic) w e t a can only con G t differ in a e n i b a parvus parvus S y b d e c u d o r p e R and forest belt of west and central Africa, pines and Java. Geographical variation affects chiefly the general C. parvus colour of the plumage and to a lesser extent wing-C.batasiensis and delta-lengths. Only in continental Africa is a distinct sub-adult plumage dis vaal and Natal, on the Gulf of Guinea islands except Annobon, on does not require correction. In view of Baker’s (1927) facts and the islands of Pemba, Zanzibar, the Comoros and Madagascar. calling the Asiatic species should be amended to cernible. alphabet is of little importance; is unlikely to be a is batassia; that Latham had forgotten to cross the ‘t’ in his MS., the African in that in the juvenal plumage the fifth rectrix has the shape and Ripley’s (1961) support sound nomenclature is best Baker’s serveddecision. by The use of one ‘s’ or two in representing a word and that in view of this slip of the pen name ( is ‘balassia’. BakerLatham (1927)(1823) pointedwho called The outit thethatoriginal Balassian the SwiftspellingBengali because in nametheGray Bengali (1829) is balasiensis, balassiensis Palm Swift and more than any African race does. as a race of birds are doubtless derived from those of Africa, and are best treated with a slightly feathersshorter in delta-lengthjuvenal ofplumage, and emarginate fifth rectrices albeit “s” versus ‘ss’ in the middle and "t” versus ‘1’ in the third letter. throat is well streaked. emarginationIt lays of a theclutch sub-adult of threefifth eggs,rectrix not oftwo African as in birds, and the (batassia) normally written the Bengali (or any other non-Latin) The darkest races of The name ) . parvus gracilis 2 1 0 2 parvus. C.gracilis d breeds throughout ethiopian Africa south to the Trans e superspecies since they differ from nominate t in Madagascar, and all live in high rainfall areas. In parvus, a breeds in India and Ceylon east to Hainan, the Philip d batasiensis ( r e C.batasiensis GEOGRAPHICAL VARIATION h s i though they could be treated as a species within l b u P and has three other spellings in the literature: e parvus possesses the streaky throat, buffy tipped h batasiensis. by R. K. Brooke t Cypsiurus batasiensis. y b the Asian Palm Swift. batassiensis. d are e t n C.parvus a r g griveaudi brachypterus Ripley (1961) concurred in e c n balasiensis c. lapsus calami e There are two variants: c 2,5 cm. The Madagascar i can be called the African l r e in the Comoro Islands d n u in the evergreen y lapsus calami and is based on a w e ) ) Gray’s name t a G parvus t e n i b a and far S 219 y b d e c u d o r p e R 220 Geographical Variation in Palm Swifts Cypsiurus Spp. creasing pallor appears successively in myochrous of the eastern plateaus. from Uganda to the Transvaal, laemostigma of Kenya and the eastern lowlands from Somalia to Natal, parvus from Senegal to the Sudan, and hyphaenes in northern Botswana to south-western Angola. The increasing pallor is matched by the increasing aridity of the environment. Wing-lengths and adult delta-length averages correspond. The form with longest measurements is hyphaenes, and in descending order thereafter we find (Table 1) southern laemostigma, myochrous, parvus, brachypterus, northern laemostigma, griveaudi and gracilis. The rather small weight samples do not fall into quite the same order as the linear measurements: in descending order they are southern laemostigma, myochrous, hyphaenes, brachypterus and northern laemostigma. Since the difference between the continental races of C.parvus are largely ones of shade and tone of colour with minor differences in weights and lengths, it might be held that no such races should be recognised. However, the zones of intergradation are narrow and two of the most distinct races, parvus and brachypterus, abut without ) . apparent intergradation in the area where the Sudan, Uganda and 2 1 north-eastern Zaire meet. There is no evidence for overlap so there 0 2 d is no reason to postulate more than one species in Africa, a species e t a which is polytypic, and in which the facts can be reasonably d ( represented by trinomial nomenclature. r e h s i l b A curious position holds in the evergreen forest race brachypterus, u P which has an isolated population in low-lying forests of the Haroni/ e h Lusitu confluence on the frontier of Rhodesia and Mo9ambique, a t y b thousand miles or so from the nearest Zairean population. The d e Haroni/Lusitu population is known from one specimen, which, t n a except that it is longer winged than brachypterus (see Table 1), is r g indistinguishable from it. Subspecific recognition is not warranted e c n at the present time. e c i l r e C .p .laemostigma was sunk as a synonym of myochrous by Sclater d n u (1924), but it is somewhat paler, has a heavily streaked throat, and y a its wing-length varies in a way different to that of myochrous. w e t There is no clinal variation in wing-length in myochrous, but in a G laemostigma populations south of the Rovuma River have longer t e wings and longer delta-lengths than those to the north: averages n i b 133,3, versus 128,9 mm, and 31,94 versus 27,26 mm (Table 1).