Tadpoles from Gosner stage 25 to 42 were handled using modeling clay to position the specimen, allowing detailed observations of the oral disc
Part 2 A look at features' provides detailed coverage of morphology and features for each of the lifecycle phases typical of frogs, and includes the oral disc
, an important diagnostic feature of many tadpoles.
Because preserved tadpoles undergo some degree of integument deformation through time, which may alter eye position and or vent position relative to other features, and cause fading of color pattern and other markings, we used oral disc
morphology to determine the identity of the tadpoles.
Only mouthparts of the oral disc
(i.e., labial tooth rows, papillae, and jaw sheaths; McDiarmid and Altig, 1999) of larval anurans are keratinized (Luckenbill, 1965), and these are the sites of Bd infection (Knapp and Morgan, 2006).
The ethological changes were accompanied (like oral disc
closure, wilting, and swelling) in the experiment.
For example, Johnston (1982) showed that after grazing on algae, tadpoles left marks on the substrate, and suggested that labial teeth anchored the oral disc
to the substrate while the tadpoles removed food from the substrate with their jaw sheaths.
Chemical elimination is effective, but requires the laborious introduction of toxic injections directly into the oral disc
of each anemone.
microcephalus group are considered to have extreme reduction and modification of the elements of the oral disc
Six structures of the coral were assayed: oral disc
, tentacles, costae, septa, calice, and coenosarc.
5): total length 43.6; body length 14.4; tail length 29.2; height of caudal musculature, at base of tail, 5.3; width of caudal musculature, at base of tail, 3.7; tail maximum height 8.7; maximum height of dorsal fin 2.5; maximum height of ventral fin 2.0; maximum body width 8.3; maximum body height 7.0; eye diameter 1.7; interorbital distance 3.4; snout-base of spiracle distance 8.2; nostril-eye distance 1.7; oral disc
transverse diameter 5.0.
Prior to use, 3-year dark-treated anemones (n = 180) with oral disc
diameters of about 2 to 3 mm were placed in 100-ml containers filled with filtered (0.45 [[micro]meter]) seawater (FSW).
1) (measurement in mm): body length 16.2; maximum body width 8.9; tail length 27.3; total length 43.5; oral disc
diameter (transverse) 5.4; eye diameter 1.9; interorbital distance 5.2; internostril distance 4.8; width of caudal musculature 4.9; maximum tail height 9.5; body slightly depressed; snout rounded in dorsal view and profile; eyes small (diameter of eye 11.7 % of body length), dorsal, not protuberant; nostril opening ovoid, not prominent, anterolaterally directed, located slightly closer to eye than to tip of snout; spiracle sinistral, angled 45 degrees with respect to horizontal plane of body; opening of spiracle located at midline of body, slightly closer to end of body than to tip of snout; inner wall of spiracle free from body (Altig and McDiarmid, 1999; Fig.