Ascidian larval nervous system: Primary sensory neurons in adhesive papillae

  title={Ascidian larval nervous system: Primary sensory neurons in adhesive papillae},
  author={Steven A. Torrence and Richard A. Cloney},
SummaryThe three anterior adhesive papillae of Diplosoma macdonaldi serve to attach the larva to the substratum at settlement. Each is a cup-shaped, epidermal organ with a bulbous axial protrusion. Approximately 50 sensory neurons (anchor cells) are distributed around the rim of each papillar cup within the epithelium. An axon from each passes within the wall of the cup to the base of the papilla and thence in the hemocoel to the visceral ganglion. Microvilli arising from anchor cells form a… 
Neurons of the ascidian larval nervous system in Ciona intestinalis: II. Peripheral nervous system
Two additional types of tail neuron, the caudal epidermal neurons (dorsal and ventral) as well as a novel bipolar interneuron, were identified and are the substrate for the ascidian larva's entire peripheral sensory input, important during larval swimming and settlement.
Differentiation of papillae and rostral sensory neurons in the larva of the ascidian Botryllus schlosseri (Tunicata)
During the metamorphosis of tunicate ascidians, the swimming larva uses its three anterior papillae to detect the substrate for settlement, reabsorbs its chordate‐like tail, and becomes a sessile
Ultrastructural comparative analysis on the adhesive papillae of the swimming larvae of three ascidian species
The investigations, carried out at ultrastructural level and at confocal laser microscope, have evidentiated a clear fluorescence in the papillae of the three studied species and a network of nervous fibers projecting from the papilar base up to cerebral vesicle of the cephalenteron.
Comprehensive morphological analysis of individual peripheral neuron dendritic arbors in ascidian larvae using the photoconvertible protein kaede
  • T. YokoyamaK. HottaK. Oka
  • Biology
    Developmental dynamics : an official publication of the American Association of Anatomists
  • 2014
This study reveals the organization of ESN sensory fields in the ascidian larval tunic, suggesting that the ASNET is formed in a regulated, non‐random fashion.
Distribution and structural diversity of cilia in tadpole larvae of the ascidian Ciona intestinalis.
Cement gland apparatus of the angelfish Pterophyllum scalare (Teleostei, Cichlidae): Functional morphology in comparison with adhesive organs of other Chordata
chronological differences in development and functionality lead to a morpho‐functional situation only apparently different from the adhesive structures of Chordata, thus allowing the larva to remain anchored until it reaches an advanced stage of development, with muscles allowing autonomous movements.
Immunohistochemical analysis of adhesive papillae of Clavelina lepadiformis (Müller, 1776) and Clavelina phlegraea (Salfi, 1929) (Tunicata, Ascidiacea)
It is suggested that the central neurons of C. lepadiformis may be chemo- or mechanoreceptors that sense the substratum, and the peripheral ones may be involved in the mechanism that triggers metamorphosis.
Neural Map of the Larval Central Nervous System in the Ascidian Ciona intestinalis
We examined the distribution patterns and axonal pathways of cholinergic, GABAergic, and dopaminergic neurons in the central nervous system of Ciona intestinalis larvae, based on the expression
The Evolution of Sensory Placodes
  • F. Mazet
  • Biology
  • 2006
Molecular work demonstrated that some sensory placodes (namely the adenohypophysis, the olfactory, and accoustico-lateralis placodes) first evolved at the base of the chordate lineage, while others might be specific to vertebrates.
Expression of smooth muscle-like effectors and core cardiomyocyte regulators in the contractile papillae of Ciona
It is proposed that the axial columnar cells of Ciona are a myoepithelial cell type required for transducing external stimuli into mechanical forces that aid in the attachment of the motile larva to its final substrate.


Larval adhesive organs and metamorphosis in ascidians
The cup-shaped adhesive papillae of Distaplia occidentalis evert at the onset of metamorphosis and each transforms into a hyperboloidal configuration and the myoepithelial cells are the driving force in papillary eversion.
The results indicate that Corella is a primary colonizer, preferring to settle on clean surfaces, and growth is rapid during the summer, but individuals grow at a slower rate and live longer during the winter; the life span then is seven or eight months.
Larval behavior and post-settling morphology in the ascidian, Chelyosoma productum Stimpson
The Gonads, Larvae, and Budding of the Polystyelid Ascidians Stolonica and Distomus
  • N. Berrill
  • History
    Journal of the Marine Biological Association of the United Kingdom
  • 1948
The relationship of the budding styelid-like ascidians of Stolonica socialis and Distomus is discussed further, after descriptions have been given of the breeding cycles of these species.
Development of the sense organs of the larva of Botryllus schlosseri
A study of the development of the sense organs of the larva of Botryllus schlosseri to determine, if possible, any homologies between its sense organs and those of other types of ascidians such as
Attachment of the larva of the ascidian Diplosoma listerianum
Histological and ultrastructural studies of free-swimming and attached larvae of Diplosoma listerianum Milne Edwards indicate that initial attachment is by means of papillae, which secrete an
Larval structure and activity in the ascidian Metandrocarpa taylori
Nervous system of ascidian larvae: Caudal primary sensory neurons
In larvae of Diplosoma macdonaldi one sensory nerve extends along the dorsal midline of the tail and another extended along the ventral midline and it is proposed that these cells are mechanoreceptors.
Factors influencing the settlement of marine invertebrate larvae
  • 1974