Genera

Microraptor

“small plunderer”

CLASSIFICATION

Microraptor
 Xu, Zhou & Wang, 2000TYPE SPECIES:
M. zhaoianus Xu, Zhou & Wang, 2000 “Zhao Xijin’s small plunderer”
Animalia Vertebrata Tetrapoda Sauropsida Archosauromorpha Ornithodira Dinosauria Sauropodomorpha

see alsoGenus IndexClassification


MEASUREMENTS

LENGTH:M. zhaoianus: 40 cm to 50 cm

see alsoWorld Records


TIME

M. zhaoianus: middle Barremian

see alsoAges of the Mesozoic


PLACE

M. zhaoianus: China

see alsoPaleo-Maps


REMAINS

  • M.zhaoianus
    • [holotype]: articulated skeleton missing middle portion, with patches of preserved integument

see alsoAnatomy


ESSAY

THE “T
INY RAPTOR”:Possibly the smallest non-
avian dinosaur, assuming (as the authors do) that is is fully grown.
PLACEMENT:The counterslab to the hindquarters of this specimen was already published as half of the chimerical Archaeoraptor liaoningensis. The front half of that specimen is actually an avialan.
Although the authors classified this species as a dromaeosaurid, it has troodontid features (arctometatarsalian pes, “waisted” teeth, maxilla bordering naris, closely packed dentary teeth) and avialan features (Rahonavis-like ischium, avian features of the teeth, maxilla bordering naris) as well. Some features (rod-like extensions of prezygaopohyses which stiffen the tail, large second pedal ungual) are dromaeosaurid-like. Hopefully this species can shed light on how the three groups are related to each other.
Wherever this species belongs, it does not appear to be avian, and thus dispels notions that dinosaurs were too big to be bird ancestors. (This species is smaller than Archaeopteryx, the most primitive bird known.)
S
MALL AND
 FUZZY:Feathers or (feather-like integument with a rachis, or vane) similar to those of Beipiaosaurus and Sinornithosaurus are preserved. They are found near the femur, tibia, and ischium.
A
 CLIMBER?:Some features of this species have been interpreted as indicating a scansorial lifestyle. These include distally placed metatarsal and pedal digit I.
T
RANSITIONAL TEETH:Microraptor has heterodont teeth, the anterior ones being more recurved and laterally compressed and lacking serrations. They are more bird-like than the posterior teeth, and thus may indicate that avian dental traits began in the front and spread to the back over the course of evolution.
T
ROUBLE WITH THE NAME:Technically, by ICZN rules, this animal should be referred to as Archaeoraptor liaoningensis. However, there will be a petition to reject that name and conserve the name Microraptor zhaoianus. In the hope that this petition goes through, I am using the name Microraptor despite ICZN rules. See the entry on Archaeoraptor for more on this nomenclatural debacle.

답글 남기기

이메일 주소는 공개되지 않습니다. 필수 필드는 *로 표시됩니다