Symmetry of priapulids (Priapulida). 1. Symmetry of adults

Adrianov, Andrey V.; Малахов, В. В.

doi:10.1002/1097-4687(200102)247:2<99::aid-jmor1005>3.0.co;2-0

Cited by 36 publications

(30 citation statements)

References 13 publications

(12 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Wills suggested that the Tubiluchidae were a link between Cambrian and Recent priapulids [18] . The general characteristics of Tubiluchidae are: (1) an swollen introvert with 20-25 rows of scalids; (2) well-defined neck area; (3) a trunk covered with tumuli without annulations; (4) a caudal appendage smooth and slender; (5) pharyngeal teeth pectinate, arranged quincunxially without distinct circles [15,17,19,20] . Han et al described Paratubiluchus bicaudatus as follows: introvert with 25 scalid rows, neck area wide, oval shaped trunk without annulations, pair of short caudal appendages [11] .…”

Section: Discussion On the Systematic Position Of Paratubiluchus Bicamentioning

confidence: 99%

Discussion on the systematic position of the Early Cambrian priapulomorph worms

2006

View full text Add to dashboard Cite

Section: Discussion On the Systematic Position Of Paratubiluchus Bicamentioning

confidence: 99%

Discussion on the systematic position of the Early Cambrian priapulomorph worms

2006

View full text Add to dashboard Cite

“…Unfortunately, few details of priapulid development are known; priapulids are largely radially symmetric around the oral-aboral axis, as are the even less understood loriciferans. Radial symmetry is thought to be a derived state associated with the infaunal mode of life (Nebelsick 1993;Adrianov and Malakhov 2001). Priapulids have numerous dermal elements, but serial elements are much less discrete than kinorhynch segments.…”

Section: Modes Of Bilaterian Evolution Given Terminal Addition As An mentioning

confidence: 99%

Terminal addition, the Cambrian radiation and the Phanerozoic evolution of bilaterian form

Jacobs

Hughes

Fitz‐Gibbon

et al. 2005

Evolution and Development

View full text Add to dashboard Cite

SUMMARYWe examine terminal addition, the process of addition of serial elements in a posterior subterminal growth zone during animal development, across modern taxa and fossil material. We argue that terminal addition was the basal condition in Bilateria, and that modification of terminal addition was an important component of the rapid Cambrian evolution of novel bilaterian morphology. We categorize the often-convergent modifications of terminal addition from the presumed ancestral condition. Our focus on terminal addition and its modification highlights trends in the history of animal evolution evident in the fossil record. These trends appear to be the product of departure from the initial terminal addition state, as is evident in evolutionary patterns within-fossil groups such as trilobites, but is also more generally related to shifts in types of morphologic change through the early Phanerozoic. Our argument is contingent on dates of metazoan divergence that are roughly convergent with the first appearance of metazoan fossils in the latest Proterozoic and Cambrian, as well as on an inference of homology of terminal addition across bilaterian Metazoa.

show abstract

“…However, their body chiefly displays bilateral symmetry [25,26] . Some, such as Priapulus, indeed have a single appendage [8,10] whereas the posterior retractor muscles and urogenital ducts are paired, indicating that the terminal structures in early priapulids, which are thought to be more primitive, might have been paired.…”

Section: Comment On the Evolution Of The Terminal Structures Of Priapmentioning

confidence: 99%