Pelvic-Fan Flaring and Inflation in the Three-Tooth Puffer, Triodon macropterus (Tetraodontiformes: Triodontidae), with Additional Observations on Their Behavior in Captivity
Katherine E. Bemis, James C. Tyler, Atsushi Kaneko, Keiichi Matsuura, Kiyomi Murakumo, Vinicius C. Espíndola, Jean-Lou Justine, Diane M. Tyler, Matthew G. Girard, and William E. Bemis
Ichthyology & Herpetology 111: 222–240
Supplemental Figure 1. Photographs of Triodon macropterus demonstrate different levels of inflation. Images were found by contacting colleagues or searching “Triodon macropterus” in Google Images. Many of the photographs represent individuals that were caught by anglers but were not deposited in a museum or aquarium. Written permission received to publish images; see Supplemental Table 1 for collection data and photographers.
Supplemental Figure 2. Four individuals of Triodon macropterus at the Okinawa Churaumi Aquarium, 22 April 2019. Caudal-fin damage caused by intraspecific fin biting is visible on the individual in the front of the frame (white circle). Such behavior is occasionally observed in the aquarium when individuals of T. macropterus are housed together.
Supplemental Figure 3. Movement of 320 mm SL (Fish 3) Triodon macropterus at night at the Okinawa Churaumi Aquarium. Images are from a video taken during the evening of 22 to 23 November 2020. Frames were extracted every 30 minutes during a ten-hour period of continuous taping in the darkened aquarium room. Triodon macropterus was slower and less active during the night than during the day, and it usually had no interactions with other fishes. Except for two pelvic-fan flaring events, the T. macropterus individual was relatively quiescent during the night, mostly hovering in place with the use of its pectoral, dorsal, and anal fins to maintain its position relative to the reef. Occasionally it moved vertically (both up and down) about one meter or less, and occasionally it moved horizontally as much as a few meters along the face of the reef. White circles indicate T. macropterus when visible.
Supplemental Video 1. Pelvic-fan flaring type 1: gradual flaring. A wild Triodon macropterus observed at 275 m depth by a remotely operated vehicle (ROV) Hakuyo 2000 east of Ishigaki-jima Island in the Ryukyu Islands, 23 March 2006. First reported by Matsuura et al. (2017: fig. 5).
Supplemental Video 2. Pelvic-fan flaring type 2: pump flaring. The pelvic fan became fully flared within 15–20 seconds after a series of 13 yawns and 10 or 11 pump-like extensions and partial retractions of the fan, each one resulting in greater expansion of the fan. Fish 3; same event is shown in Figure 4.
Supplemental Video 3. Pelvic-fan flaring type 3: rapid flaring. Recording of a 25 cm individual collected 6 January 2005 swimming up to, and aggressively flaring at, a Squirrelfish (Ostichthys kaianus). Recorded on 3 February 2005.
Supplemental Video 4. Nine-second clip from an ultrasound examination of Fish 2, Trial 2. Note two swallowing movements that resulted in water swirling in the stomach (at 2 seconds and at 7 seconds). See Figure 6 for orientation. Examination was done by Kiyomi Murakumo. Fish was restrained by Atsushi Kaneko.
Supplemental Video 5. Quivering of the pelvic fan during flaring at night. Fish 3.
Supplemental Video 6. Sand blowing in Triodon macropterus at the Okinawa Churaumi Aquarium. Blue represents the tank bottom. Sand depressions were created by a 376 mm SL individual (Fish 2) blowing water out of its mouth at the sand, presumably in search of food. Depressions in the sand remained three days after the fish was observed blowing into the sand, indicating that the depressions can persist in the tank environment.