DOI: 10.5061/dryad.jm63xsjk7
title: A hydrodynamic antenna: novel lateral line design in the tail of myliobatid stingrays

description: Eagle rays, cownose rays, and manta rays (family Myliobatidae) have a
 slender tail that can be longer than the animal’s body length, but its
 function and structure are unknown. Using histology, immunohistochemistry,
 and 3D imaging with micro-CT scans, we describe the anatomy and function
 of the tail of Rhinoptera bonasus, the cownose ray. The tail is an
 extension of the vertebral column with unique morphological
 specializations. Along the tail after the barb, vertebral centra are
 absent, and neural and hemal arches fuse and form a solid mineralized
 structure that we termed caudal synarcual which imparts passive stiffness
 to the tail, reducing bending. Two lateral lines extend along both sides
 of the tail. The lateral lines are composed of a main canal connected to
 an extensive network of tubules, which extends and ramifies toward the
 dorsal and ventral tail surfaces and opens to the surrounding water via
 small pores. A remarkable continuous neuromast is located within each main
 canal. The complex lateral line sensory system in the myliobatid ray tail
 supports the hypothesis that the tail of myliobatids functions like a
 hydrodynamic sensory antenna extending posterior to the body and may play
 an important role in their behavioral and functional ecology.
description: Data published in this data set was obtained throught a
 combination of different methods. They were applied as follows: 
 <strong>1. Histology:</strong>
 Histology was used to identify the different tissues and their
 arrangement in the tail, sections were stained with hematoxylin-eosin (HE)
 combined with Orange G or with Mallory trichrome. Histology-stained
 samples were imaged using a Keyence digital microscope VHX-600 (Keyence
 Corporation) and a Leica light microscope (Leica Microsystems GmbH).
 Images were analyzed using Fiji 2.0.0. <strong>2.
 Immunofluorescence imaged with Confocal and Fluorescence
 Microscope:</strong> Immunofluorescence staining
 was used to identify nervous tissue within the tail by staining the
 sections with ß-III-tubulin antibody. For antigen retrieval, samples were
 incubated in 10 mM sodium citrate buffer with 0.05% Tween 20 (pH 6) for 6
 hours at 60ºC. Samples were permeabilized in PBS with 0.025% Triton X-100
 and blocked with 5% bovine serum albumin in PBS (BSA; Sigma Aldrich) for 2
 hours at room temperature. The primary antibody β-III-tubulin (1:500;
 Abcam, Cat# ab18207) was used as a neuronal marker due to its previously
 demonstrated reactivity with catshark tissues. Samples were incubated with
 the primary antibody in 1% BSA in PBS overnight and then incubated for 1
 hour at room temperature with the secondary antibody goat anti-mouse IgG
 H&L Alexa Fluor 488 (1:500; Abcam, Cat# ab150113) diluted in 1%
 BSA and then rinsed in PBS. Some tissue structures displayed an
 autofluorescence signal at 488nm. To avoid interference with the antibody
 signal, samples were stained with 0.1% Sudan Black B (Sigma Aldrich)
 following protocols established. Samples were washed in PBS to remove
 excess stain and mounted with SlowFade<sup>TM</sup> Diamond
 antifade mountant with DAPI (ThermoFisher). This mountant with DAPI added
 additional autofluorescence signal when the samples were excited with a
 405 nm laser, especially in the dermis. However, this did not affect the
 visualization of the structures of interest. Images of
 sections stained with immunofluorescence were acquired using a Zeiss LSM
 980 confocal microscope (Carl Zeiss GmbH) and a Leica DM R fluorescence
 microscope (Leica Microsystems GmbH).  <strong>3.
 Micro-CT scans</strong> High-resolution µCT scans
 were conducted to image in 3D the tissues forming the tail, enabling
 fine-scale morphological analyses. Samples fixed in 4% PFA were washed in
 PBS and transferred into increasing ethanol concentrations (10%, 30%, and
 50%) up to 70% ethanol. High-resolution µCT images were obtained using a
 Bruker SkyScan 1273 (70 kV and 114 uA). Image pixel size ranged between
 4.9 and 13 µm. Samples were post-stained in 0.3% phosphotungstic acid
 (PTA, AMRESCO) for over a month, changing PTA solution every two weeks to
 ensure a complete staining. After staining was complete, PTA-stained
 samples were transferred to 70% ethanol and re-scanned. 
description: # A hydrodynamic antenna: novel lateral line design in the tail of
 myliobatid stingrays
 [https://doi.org/10.5061/dryad.jm63xsjk7](https://doi.org/10.5061/dryad.jm63xsjk7) ## Description of the data and file structure This dataset consists of raw data used for tor this manuscript. Raw data were obtained through various imaging techniques applied to *Rhinoptera bonasus'* tail samples and used in a variety of figures. The details are as follows: **1. Histology:** * Files: `.tif` * Description: Raw data from histological sections stained with Hematoxylin-Eosin + Orange G or Mallory Trichrome. * Files are named using the species name + staining used.  * Used in Figures 1, 2 and 3. **2. Confocal Microscopy:** * Files: `.czi` * Description: Samples immunolabeled with ß-III-Tubulin antibody and DAPI, imaged using a Zeiss Confocal Microscope * Data used in Figure 5. **3. Fluorescence Microscope** * Files: `.jpeg & .tiff` * Description: Samples immunolabeled with ß-III-Tubulin antibody and DAPI, imaged using a Leica DM R fluorescence microscope. * Files are named with a number (1, 2, 3, etc). Files with the same number indicate same tissue structures imaged with different channels: Bright Field (BF), ß-III-tubulin (green), and DAPI (blue).  * Data used in Figures 4 and 5 and Supplementary Figures 2 and 4. **4. Micro-CT scans** * Files: `.avi` * Description: Raw micro computed tomography (CT) scans of both non-stained and PTA 0.03%-stained samples. These scans were further processed using AMIRA Avizo and MeshLab. * File name indicate specimen, tail position (base, middle or tip), and staining (PTA or unstained). * Data used in Figures 1, 2, 3 and 4, Supplementary Figure 3 and Supplementary Videos 1 and 2.