Dataset: Goby taste bud data

Methodology:

Fish Collection and Rearing (for all histological and SEM analyses) - Mated pairs of E. lori and of E. colini were collected from reef habitats near Carrie Bow Caye, Belize and housed in 75-l aquaria in a flow-through seawater lab at the International Zoological Expeditions (IZE) field station on South Water Caye, Belize, or in a recirculating seawater system at Boston University, USA. Ontogenetic series of E. lori and E. colini larvae were reared in 76-l cylindrical black bins and fed a variety of cultured and wild-caught zooplankton (Figure 1). A detailed description of brood stock maintenance and larval rearing methods can be found in Majoris et al. (2018). Additional post-settlement E. lori and E. colini (settlers) were collected from reef habitats within the South Water Caye Marine Reserve. Field research in Belize and the export of samples from Belize was carried out with the approval of the Belize Fisheries Department. Fish were immersed in cold seawater (2-4 degrees C) for two minutes and then fixed in cold (2-4 degrees C) 10% formalin in seawater (or in phosphate-buffered saline, PBS) for at least two minutes for anatomical study, which is consistent with AVMA Guidelines on Euthanasia of small warm-water fish. Care was taken to ensure that fish did not contact ice directly. Chemical anaesthetic was not used for several reasons, in particular because fixation must occur prior to death to avoid post-mortem changes at the cellular level, and ensure quality of the histological data and specimens prepared for SEM.

Taste Bud Analysis - Individual taste buds (~15-20 m in diameter) were present in multiple sections, so other landmarks (e.g. eye, skeletal features) were used to distinguish between individual taste buds to ensure accurate counts. Taste buds were counted in four regions: 1) oral jaws, lips, and buccal valves, 2) roof of the buccal cavity, 3) floor of the buccal cavity, including the basihyal and basibranchial (the tongue), and 4) gill arches, including taste buds located between pharyngeal teeth. In order to assess rostro-caudal distribution of taste buds within the buccal cavity, the head of each individual was divided into ten equal bins along the rostro-caudal axis, extending from the lips to the anterior end of the esophagus (beyond which taste buds were not found) and the total number of taste buds was calculated for each bin.

Note: for olfactory size, measurements were taken on histological sections at 25 (position 1), 50 (position 2) and 75% (position 3) along the rostro-caudal length of the olfactory epithelium.