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NUMBER 89 221
Costae: Deformed fragments of four left ribs can be seen
in the paratype. No processus uncinati can be detected.
Sternum: Pieces of the sternum are preserved only in the
paratype. They are badly crushed, covering as a thin layer parts
of the ribs and femur.
Furcula: The furcula is thin and U-shaped. There is no hypocleideum.
In both specimens the dorsal ends of this bone are
insufficiently preserved. The thickness of the scapus is continuously
about 1 mm.
Coracoideum: In the holotype, fragments of the coracoids
are deformed past recognition. In the paratype they are in better
condition. They have a slender shaft and a rather small extremitas
omalis. The presence of a processus procoracoideus is uncertain.
Unfortunately, the lateral and medial parts of the extremitates
sternales are only partly preserved. What can be
seen, especially from the left coracoid of the paratype, suggests
abroad sternal extremity. Maximal length of the coracoid is approximately
16 mm.
Scapula: Parts of the left scapula of the holotype and of
both scapulae of the paratype are preserved. All three bones
have an even, ribbon-like shape, without any terminal enlargement.
They are 1.6-1.7 mm broad. The cranial extremities are
hidden by other bones.
Humerus: All humeri have the cranial surfaces exposed.
They are robust, slightly curved, and approach in shape the humerus
of Anneavis Houde and Olson, 1992, but have the tuberculum
dorsale and epicondylus dorsalis less prominent (fide
Houde and Olson, 1992, fig. 8). The length is 21 mm and the
midshaft width is 3 mm.
Ulna: The ulna is stout, only slightly curved, and of the
same length as the humerus or slightly shorter.
Radius: The radius is straight and robust. The extremities
are not well preserved.
Os carpi radiale and o. c. ulnare: In the holotype a deformed
ossicle attached to the distal end of the left ulna might
be the o. c. ulnare, and both carpalia are preserved in the right
hand of the holotype and in the left hand of the paratype. Their
condition is so bad, however, that no useful details can be detected.
Carpometacarpus: This is a robust bone. Apparently, the
processus extensorius was only moderately protuberant. No
processus intermetacarpalis is present. The proximal end of the
os metacarpale minus has a rectangular flange projecting ventrally.
A blurred structure in the paratype suggests that this
flange might have been perforated, as in Coracias garrulus
Linnaeus. The length is 14-15 mm, and the distal-end width is
4.5 mm.
Digitus alulae: In the holotype a small ossicle at the tip of
the digit of the left hand very probably represents the second
phalanx of this digit. The length of the first phalanx is 6 mm.
Digitus major: The proximal phalanx is not fenestrated and
approaches the shape of that of Passeriformes. Measurements
are as follows: phalanx proximalis length 6 mm, distal-end
width 3 mm; phalanx distalis length 6 mm.
Digitus minor: The only phalanx is robust; it has a triangular
outline and is about 3 mm long.
Pelvis: The small fragments in the paratype suggest that the
pelvis was rather wide. Inferring from the position of the femora,
the distance between the acetabula was about 11-12 mm.
Femur: No precise morphological details of this bone can
be imparted. Its length is about 20 mm.
Tibiotarsus: This is a slender, straight bone. In the holotype
the cranial aspect of the right tibiotarsus is exposed; in the
paratype the lateral side of the left tibiotarsus can be seen. The
latter one is broken near the distal end, and both fragments
have slipped together. In the holotype, part of the proximal end
can be seen. Apparently, the cristae cnemiales were not very
prominent, similar to the condition in Coracias. The distal end
in both specimens is very deformed. The length is 30 mm, and
the midshaft width is 3 mm.
Fibula: Not preserved.
Tarsometatarsus: The tarsometatarsus also is comparatively
slender and straight. In the holotype both tarsometatarsi have
the dorsal aspect exposed, the left one in a reversed position. In
the paratype the left tarsometatarsus is exposed lateroplantarly.
Although the bones are plastically deformed, it can be seen that
they had a small hypotarsus and an unusually small trochleae.
Both the distal and the proximal ends of the bone are only
slightly broader than the shaft. The length is 20-21.5 mm.
Ossa digitorum pedis: In the holotype the entire set of toes
is preserved; in the paratype only the toes of the left foot can be
seen in their plantar and partly lateral aspect. In the right foot
of the holotype and the left one of the paratype, the toes are in a
pamprodactyl position. In the left foot of the holotype, the configuration
seems to be anisodactyl, but this might be an artifact
because the toes are disarticulated from the tarsometatarsus.
The most striking feature is in the proportions of the phalanges
(p), as shown by the following measurements (in mm).
digit Lpl, 4.5-5.5; p 2, 4.0-4.5
digit II: p 1, 2.0; p 2, 6.0; p 3, 4.5-5.5
digit III: p 1, 2.5; p 2, 2.5-3.0; p 3, 6.0; p 4, 5.0-6.0
digit IV: p 1,2.0; p 2, 1.5-2.0; p 3, 1.5-2.0; p 4,6.0; p 5,5.5-6.0
Feathers: There are some small remnants of feathers in the
holotype (Figure 1), suggesting that the birds had quite long
remiges or rectrices.
Contents of the Digestive System: In the holotype at least 25
densely packed seeds are preserved. Surely, this was the bird's
last meal. It is difficult, however, to decide whether the seeds
were in the stomach or in the crop. The seeds obviously belong
to a dicotyledonous plant, but their identity is as yet unknown.
Discussion
Selmes absurdipes shows that not only the distribution but
also the morphological range of the Sandcoleiformes is wider
than initially presumed. The birds of this order are real taxonomic
mosaics, having similarities with many other groups.
For this reason it might be worthwhile to reflect on the defini-