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RE: Eating New Papers



--- Tim Williams <twilliams_alpha@hotmail.com>
schrieb:

> 
> Jerry Harris wrote:
> > Mayr, G. 2007. New specimens of Eocene stem-group
> psittaciform birds may > shed light on the
> affinities of the first named fossil bird,
> Halcyornis > toliapicus KOENIG, 1825. Neues Jahrbuch
> fur Geologie und Palaontologie > Abhandlungen
> 244(2): 207-213.
> I don't have the paper (as Jerry said, it's not yet
> on-line, not even at Gerald Mayr's website), but I
> do have an abstract:
>  
> Abstract: "Two well-preserved skulls of the
> stem-group psittaciform bird _Pseudasturides
> macrocephalus_ (MAYR, 1998) are described from the
> Middle Eocene of Messel (Germany). Further reported
> is a three-dimensionally preserved partial skeleton
> of a _Pseudasturides_-like bird from the Isle of
> Sheppey (England). The new Messel specimens show
> that, in contrast to previous descriptions, the
> skull of _P. macrocephalus_ exhibits well-developed
> fossae temporales. With regard to this and other
> features, e.g., the narrow interorbital bridge of
> the os frontale, the cranium of _P. macrocephalus_
> closely resembles that of _Halcyornis toliapicus_
> KOENIG, 1825, whose affinities have been uncertain
> so far. _Pseudasturides_-like birds are the most
> abundant small birds in the London Clay of the Isle
> of Sheppey, the type locality of _H. toliapicus_,
> indicating that Pseudasturidae MAYR, 1998 may be a
> junior synonym of Halcyornithidae HARRISON & WALKER,
> 1972."
>  
>  
> I know _Halcyornis_ has previously been regarded as
> a stem-coraciiform.  _Pseudasturides_ is the
> replacement name for _Pseudastur_ (preoccupied). 
> That's all I know.

See also DOI: 10.1080/08912960600641224

'"The Pseudasturidae (Mayr 1998) are a family of
extinct
birds known from the Eocene of Europe and North
America (also see above section on Pulchrapollia
gracilis). Mayr (1998, 2000, 2000a, b) assigned avian
fossils such as Pseudasturides macrocephalus (Mayr
2003; although this genus was originally described as
Pseudastur [Mayr 1998], a preoccupied name),
Serudaptus pohli (Mayr 2002b), Primobucco olsoni
(Feduccia and Martin 1976; Mayr and Daniels 1998)
and parts of the paratype of Precursor parvus
(Harrison
andWalker 1977), aswell as Pulchrapollia gracilis
(Dyke
and Cooper 2000) to this family of zygodactyl birds.
Contradicting his earlier paper placing Pulchrapollia
gracilis outside the order Psittaciformes (Mayr 2001),
Mayr (2002a) assigned Pulchrapollia gracilis (albeit
as a
conspecific of Primobucco olsoni&#8212;and therefore
Mayr
[2002a] refers to the species as Pulchrapollia olsoni)
along with the rest of the Pseudasturidae as
stem-group
members of the Psittaciformes (parrots). Derived
characters of the tarsometatarsus and overall
morphology,
link the Pseudasturidae with the Eocene
psittaciformfamily Quercypsittidae (although features
of the coracoid distinguish them as two separate
families) and are therefore referred by Mayr (2002a)
as
stem-group members of the Psittaciformes. Mayr
(2002a) considered there to be four main taxa within
the Psittaciformes:
&#8211;(the basal) Pseudasturidae (including
Pulchrapollia);
&#8211;Quercypsittidae;
&#8211;Psittacopes; and
&#8211;(crown-group) Psittacidae (Figure 10).
Mayr (2002b) noted that members of the Psudasturidae
along with all other Eocene Psittaciformes of
which the beak has been preserved, lack the derived
bill morphology of the extant Psittacidae (broad
dorso-ventral maxilla with sigmoidally curved ventral
margin, distinctly short mandible compared with
maxilla, small narial openings [Mayr and Daniels
1998]). Eocene psittaciforms also lack the highly
apomorphic morphology of the tarsometatarsus which
the Psittacidae have, as well as having differences in
the morphology of the wing skeleton (Mayr 2002b).
Mayr (2002b) pointed out that, the derived morphology
of Recent psittaciforms (Psittacidae) are all
linked to specialized feeding techniques (distinct
bill
morphology for coping with hard-shelled nuts and
seeds; modified tarsometatarsal morphology for
manipulating seeds and nuts, as well as for shelling
nuts (Steinbacher 1935; Collar 1997); reduced
furcula due to a large crop (Stegman 1964); and
modifications to the pectoral girdle and wing to
facilitate hovering flight in order to reach fruits,
etc. in
tree-tops (Stegman 1964). Indeed, as Mayr and
Daniels (1998) point out: the mousebird-like bill of
the Eocene Psittaciformes indicates a predominantly
soft vegetable diet, which concurs with
Guntert&#8217;s
(1981) statement, &#8220;The evidence presented
strongly
suggests that the ancestors of recent parrots were
forest-living birds with an unspecialized granivorous
diet&#8221;. Mayr (2002b) goes on to theorize that,
&#8220;Evolution of the specialized feeding technique
of
the Psittacidae might have been the key event that
made parrots a highly successful group with more than
300 extant species&#8221;.

Eike


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