Revisiting kinorhynch segmentation: variation of segmental patterns in the nervous system of three aberrant species

Autor(es)

Herranz, Maria ^{[1, 2]} ; Park, Taeseo ^[3] ; Di Domenico, Maikon ^[4] ; Leander, Brian S. ^[5] ; Sorensen, Martin V. ^[2] ; Worsaae, Katrine ^[1]

Afiliação do(s) autor(es)

^[1] Univ Copenhagen, Dept Biol, Copenhagen - Denmark

^[2] Univ Copenhagen, Nat Hist Museum Denmark, Copenhagen - Denmark

^[3] Natl Inst Biol Resources, Incheon - South Korea

^[4] Univ Fed Parana, Ctr Estudos Mar, Pontal Do Parana - Brazil

^[5] Univ British Columbia, Dept Bot & Zool, Vancouver, BC - Canada

• Tipo de documento: Artigo Científico
• Fonte: Frontiers in Zoology; v. 18, n. 1 OCT 21 2021.
• Citações Web of Science: 0

Resumo

Background Kinorhynch segmentation differs from the patterns found in Chordata, Arthropoda and Annelida which have coeloms and circulatory systems. Due to these differences and their obsolete status as `Aschelminthes', the microscopic kinorhynchs are often not acknowledged as segmented bilaterians. Yet, morphological studies have shown a conserved segmental arrangement of ectodermal and mesodermal organ systems with spatial correspondence along the anterior-posterior axis. However, a few aberrant kinorhynch lineages present a worm-like body plan with thin cuticle and less distinct segmentation, and thus their study may aid to shed new light on the evolution of segmental patterns within Kinorhyncha. Results Here we found the nervous system in the aberrant Cateria styx and Franciscideres kalenesos to be clearly segmental, and similar to those of non-aberrant kinorhynchs; hereby not mirroring their otherwise aberrant and posteriorly shifted myoanatomy. In Zelinkaderes yong, however, the segmental arrangement of the nervous system is also shifted posteriorly and misaligned with respect to the cuticular segmentation. Conclusions The morphological disparity together with the distant phylogenetic positions of F. kalenesos, C. styx and Z. yong support a convergent origin of aberrant appearances and segmental mismatches within Kinorhyncha. (AU)

• Processo FAPESP: 12/08581-0 - Anelídeos intersticiais: sistemática e filogenia de uma fauna negligenciada
• Beneficiário: Maikon Di Domenico
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado