Myzomela cruentata MEYER (Aves, Meliphagidae) in the Bismarck Archipelago By FINN SALOMONSEN Zoological Museum, Copenhagen. NOONA DAN PAPERS NO. 20 Very little is known about the distribution coccinea and kleinschmidti with erythrina. He and geographical variation of Myzomela had only one specimen from New Britain, cruentata in the Bismarck Archipelago. This however. During the Whitney South Sea little honey-eater, of which the males are Expedition W. F. CouLTAS collected in almost uniform bright carmine red, has its New Britain in 1932-33 and obtained main distribution in New Guinea, from three specimens of M. cruentata in the where the nominate form was described Baining Mountains at an altitude of 5000 by A. B. MEYER in 1875. Shorty after it feet, but unfortunately they were all im­ became known from the Bismarck Islands, mature specimens. Furthermore, CoULTAS and in 1878 RAMSAY separated the popu­ in 1935 collected no less than 12 specimens lation of the Duke of York Islands as of M. cruentata on Tabar Island, an island Myzomela coccinea and that of New Ireland which from a zoological view-point was as M. erythina (emended to erythrina) . In completely unknown prior to his visit. 1884 SHARPE described the birds from Recently MAYR (1955, Arner. Mus. New Britain as M. kleinschmidti. All these Novitates, No. 1707: 42-43) made a very names were based on a single specimen interesting study of the Bismarck forms each, and the descriptions were so in­ of cruentata, basing it on E1cHHORN's and adequate that GADOW ( 1884, Cat. Birds CouLTAs' collections. He described the Brit. Mus., 9: 140) synonymized them all Tabar and New Hanover birds as a new with cruentata. Subsequently, REICHENOW subspecies, cantans, adding that "the New ( 1899, Mitt. Zool. Samml. Mus. Naturk. Hanover population is somewhat inter­ Berlin, 1, no. 3: 102) accepted coccinea, but mediate between Tabar and New Ireland not the two other species. He had not birds''. On the other hand, MAYR was personally examined specimens of any of unable to define the New Britain form the three forms, however. In 1923-24 (coccinea) owing to insufficient material. In A. F. EICHHORN collected a number of 1958, however, the late THOMAS GILLIARD specimens on New Ireland and New during his expedition to the Whiteman Hanover, which were described by HAR­ Mountains in the western part of New TERT (1924, Novitates Zool., 31: 210, and Britain, collected a large series of coccinea, 32: 133). HARTERT united the populations which is now in the American Museum of of these two islands as erythrina Ramsay, Natural History, New York. adding that there were no tangible differ­ During the Noona Dan Expedition I ences between New Britain and New Ire­ collected a long series of this species in land birds, and he, therefore, synonymized New Ireland, and a smaller series (five Myzomela cruentata 119 specimens) on Dyaul Island. The latter forms juvenile hirds, therefore, have been island was previously unexplored. M. cru­ chosen as type specimens. entata is now known from New Britain, It is necessary shortly to mention the Duke of York Islands, New Ireland, New different plumages which can be distin­ Hanover, Dyaul and Tabar. The hird life guished in these hirds. The first plumage of the different islands in the Bismarck (after the natal down) is the juvenile Archipelago is now so comparatively well dress, which in comparison with the adult known that it is unlikely that this species plumage is characterized by the looser will turn up on other islands than those texture of the feathers, the smaller pro­ mentioned. portions throughout with particularly The present study was partly carried out short wings, the swollen gape and the during a visit to the American Museum of characteristic plumage pattern differing Natura! History in New York. At my dis­ from that of the adult hirds. It is possible posal were the series collected by EicH­ to distinguish the two sexes in the juvenile HORN and CouLTAS, i. e. the same material dress. This dress is very soon replaced by which was formerly utilized by MAYR. In the first adult one, in which the short addition to this I had the Noona Dan juvenile wings are retained, while the collection and, further, the series of coccinea colour pattern of the plumage is similar to collected by GILLIARD in 1958. My thanks that of the subsequent adult stages, al­ are due to the authorities of the American though somewhat more dull, at least in Museum of Natural History and to Dr. the males. Even in the adult plumages the DEAN AMADON, Chief-Curator of the two sexes can be distinguished. Department of Ornithology, for their kind Unfortunately, MAYR (loc. cit.) con­ permission to let me examine the material fused juvenile and adult females. His of Myzomela cruentata in the museum. I am descriptions of the females of erythrina and also much indebted to Dr. TH. GILLIARD cantans actually refer to juvenile specimens. for giving me access to his collection of Neither EICHHORN nor CoULTAS col­ coccznea. lected any adult females, which apparently I am confining myselfin this paper to the are difficult to collect in several species morphology and taxonomy of the Bismarck within the genus Myzomela. During the populations only, while notes on life Noona Dan Expedition I collected an habits and ecology will be published else­ adult female on both Dyaul Island and in where at a future date. New Ireland, the fi.rst ones known in the As far as the taxonomic characters are erythrina group. These females appeared to concerned, there is a major break between differ considerably in colour pattern from the populations of New Britain - Duke of the juvenile hirds. York Islands and those of the remaining Nominate cruentata and coccinea are islands. The former are very near to characterized by a strong sexual di­ nominate cruentata from New Guinea, morphism in the adult hirds, just as is the whereas the latter are strikingly different case in most other species of Myzomela. and can be separated as a special sub­ The males of nominate cruentata and division, the erythrina-group. This group coccinea are bright red, while the females comprises four subspecies, which are are olive brown with paler, greyish under rather similar, however, the most distinct parts and a facial mask of dull red. The one being the form inhabiting Dyaul Is­ juveniles are similar to the adult females. land. The juvenile hirds of these forms Contrary to the condition in these two differ much more from each other than forms the adult females of the erythrina sub­ do the adult ones, and in three of the species group are similar to the males, 120 Myzomela cruentata being only slightly duller in the colora­ noses of the subspecies and the subspecies tion. This development is of great princi­ groups which can be distinguished in the pal interest. On the other hand, there is Bismarck Archipelago. Measurements of a considerable difference between the wing and bill of all individuals from the adult females and the juvenile birds, Bismarck Islands examined are given in while, as said above, in the cruentata group Table 1. the adult females and the juvenile birds are similar. The two adult females collected ( one in Cruentata Group. New Ireland, one on Dyaul) appear to be Adult males bright carmine red. Adult very similar. Likewise, the adult males, of females with olive brownish upper parts, which sufficient material is present of all dusky greyish under parts with dull red four forms of the erythrina group, differ on chin, upper throat and forehead. mutually only rather slightly. On this Juvenile birds very similar to the adult background it is noteworthy that the females. juvenile birds are subject to a very pro­ nounced geographical variation. The masculinization of the females in ( 1) Myzomela cruentata coccznea RAMSAY, the e1ythrina group is not unique. A similar 1878. development has taken place in two other Very similar to nominate cruentata, but species of Myzomela, namely M. nigrita and adult males differing in having the M. cardinalis. In both these species as well carmine red colour slightly duller and as in cruentata the masculinization of the paler, and females in having a faint females is developed only in populations carmine tinge on the upper parts. Bill on which inhabit small or medium-sized an average slightly larger. islands, while in the mainland populations Measurements: Four adult males ( coll. the sexes are markedly different.1) In all TH. GrLLIARD) have a wing length of three species the masculinization of the 54-57 (average 55.6) mm, and bill 16-17 females represents a higher evolutionary ( average 16.6) mm, compared with wing level than the sexual dimorphism. The 55-60 (average 57.0) mm and bill 15.8- faet that in all three species masculiniza­ 16.5 ( average 16.1) mm in 35 adult males tion of females is correlated with melaniza­ of nominate cruentata measured by me. tion and with increase in size constitutes a Range: New Britain and Duke of York further parallelism. This close parallelism Islands. tends to demonstrate that the said devel­ opment represents a fundamental evolu­ tionary trend in island forms of Myzomela. Erythrina Group. It can be added tha t melaniza tion has occurred three times, independently of Adult males sombre vinaceous red.Adult each other, in the superspecies M. lafargei, females similar to adult males, but duller. inhabiting the Solomon Islands, but this Juvenile birds strikingly different from is not followed by masculinization of the adult females and subject to strong geo­ females, only by a slight increase in size. graphical variation.