Vangulifer
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| Scientific name | ||||||||||||
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| James & Olson , 1991 |
Vangulifer is an extinct genus of songbirds from the subfamily of the honeycreeper . The subfossil remains of the two known species Vangulifer mirandus and Vangulifer neophasis were discovered in 1988 by Helen Frances James in lava tubes on the southern slopes of the Haleakalā shield volcanoon Maui andscientifically described in1991 by James and Storrs Lovejoy Olson .
etymology
The generic name is an allusion to the peculiar, blunt, somewhat spatula-shaped appearance of the beak. It is derived from the Latin term vangula , the diminutive of vanga , and means "small shovel". The addition - ifer stands for "carrier".
features
Instead of a finch-like beak, the representatives of this genus had a long, fine, broad, fairly deep beak, which culminated in a very blunt, rounded tip. The combination of a long beak with a rounded tip can only be found in the clothes birds of the genus Aidemedia , which is also considered extinct. In contrast to the genus Vangulifer , the representatives of the genus Aidemedia had shorter and wider beaks with a slight lateral narrowing of the upper jaw and a much shorter extension behind the temporomandibular joint (processus retroarticularis) of the lower jaw . Further differences to the clothes birds with finch-like beaks were the elongated nostrils running from front to back, very weakly developed rear and laterally limited side ridges and fine lower jaws with a long and thin-walled symphysis mandibulae . The middle part of the branch of the mandible is narrow and straight and does not suddenly curve downwards, as in the nectar-eating hare-bird genera Himatione , Vestiaria , Palmeria , Drepanis and Ciridops , which Robert Cyril Layton Perkins classified in 1903 in Division 1. Compared to these genera and to the genera Loxops and Aidemedia , the process behind the temporomandibular joint in the genus Vangulifer is poorly developed. As with some species of honeysuckle with finch-like beaks and most species with thin beaks, the posterior (posteroventral) edge of the upper jaw is V-shaped. The central furrow on the lateral upper jaw shows a special development: the main furrow, which in other genera runs straight from the rear edge to the tip, is flat in the genus Vangulifer and spreads outwards into numerous secondary furrows that extend outwards to the stretch the lateral edges of the maxillary bone.
It is unknown what function the beak had in foraging for food. The most realistic guess would be a comparison with living forms with a more similar morphology . However, the researchers have not yet been able to find a suitable counterpart to Vangulifer . The beak seems too long and weak to crack seeds, too deep and wide to dig into the bark and too blunt to drink nectar with. Although the possibility has also been considered that the vangulifer species may have used their beaks for snapping insects in flight, insectivorous birds such as the todis (Todidae) and the flycatchers (Muscicapidae) have a more dorsoventral (dated Back to the belly) than is the case with the genus Vangulifer .
die out
The age of the subfossil material is dated to the Holocene . The exact cause and time of extinction are unknown.
literature
- Olson, Storrs L .; James, Helen F. (1991): Descriptions of Thirty-Two New Species of Birds from the Hawaiian Islands: Part II. Passeriformes . Ornithological Monographs 46: p. 62-66. PDF online .
- Harold Douglas Pratt : The Hawaiian Honeycreepers . Oxford University Press, 2005, ISBN 0-19-854653-X . P. 224
- Hume, Julian P., Michael P. Walters: Extinct Birds . 1st edition. T & AD Poyser, London 2012, ISBN 978-1-4081-5725-1 , Fringillidae, pp. 299-300.
Individual evidence
- ^ Perkins, RCL 1903. Vertebrata. Pp. 365-466 in: Fauna Hawaiiensis or the zoology of the Sandwich. Vol. 1, pt IV (Isles, Hawaiian, Ed.) Univ. Press, Cambridge, UK