Giant dragonfish

Giant dragonfish The giant dragonfish as drawn by Else Bostelmann for Beebe. Classification Osteichthyes Proposed scientific names Bathysphaera intacta (Beebe, 1932) Bathysphaera intangibilis (Beebe, 1944) Other names Sea reported Atlantic Ocean First reported 1932 Prominent investigators • William Beebe

The giant dragonfish (Bathysphaera intacta) or untouchable bathysphere fish was a cryptid deep sea fish reported once, off Bermuda in the Atlantic Ocean, during a bathysphere dive by William Beebe on 22 September 1932. Beebe classified it as a giant form of barbeled dragonfish in the family Stomiidae, although at 6 ft (1.8 m) long, Bathysphaera was five times as large as the biggest recorded dragonfish.

Description

The giant dragonfish resembled a barracuda, or a barbeled dragonfish of the species Melanostomias bartonbeani, but with several differences. Most notable among these was its size: Beebe estimated that the pair he saw were at least 6 ft (1.8 m) long. In addition, while most dragonfish have two lines of bioluminescent photophores, these fish had only a single row of "strong lights, pale bluish ... strung down the body".

Like other dragonfish, it had short, strongly undershot jaws which "were kept wide open all the time [he] watched them," "numerous fangs which were illumined either by mucus or indirect internal lights," vertical fins placed well back on the body, and "two long tentacles, hanging down from the body, each tipped with a pair of separate, luminous bodies, the upper reddish, the lower one blue. These twitched and jerked along beneath the fish, one undoubtedly arising from the chin, and the other far back near the tail". Their eyes were large in comparison to their body size.

Sightings

1932

From 1930 to 1934, Beebe and his colleague Otis Barton (1899 – 1992), based on Nonsuch Island in Bermuda, performed several pioneering deep sea dives in a bathysphere, an cable-operated submersible designed by Barton. These record-setting dives allowed them to observe deep sea life alive for the first time. Marine journalist Jon Bowermaster has suggested that the comparative silence of the unpowered bathysphere, compared to modern deep-sea submersibles, could have allowed larger fish to approach Beebe and Barton. During one such dive, on 22 September 1932, some three miles out from Nonsuch Island and Castle Roads, Beebe observed the giant dragonfish at a depth of 2,100 ft (640 m). Beebe described the sighting in his book Half Mile Down (1934).

“

Several minutes later, at 2100 feet, I had the most exciting experience of the whole dive. Two fish went very slowly by, not more than six or eight feet away, each of which was at least six feet in length. They were of the general shape of large barracudas, but with shorter jaws which were kept wide open all the time I watched them. A single line of strong lights, pale bluish, was strung down the body. The usual second line was quite absent. The eyes were very large, even for the great length of the fish. The undershot jaw was armed with numerous fangs which were illumined either by mucus or indirect internal lights. Vertical fins well back were one of the characters which placed it among the sea-dragons, Melanostomiatids, and were clearly seen when the fish passed through the beam. There were two long tentacles, hanging down from the body, each tipped with a pair of separate, luminous bodies, the upper reddish, the lower one blue. These twitched and jerked along beneath the fish, one undoubtedly arising from the chin, and the other far back near the tail. I could see neither the stem of the tentacles nor any paired fins, although both were certainly present. This is the fish I subsequently named Bathysphaera intacta, the Untouchable Bathysphere Fish.

”

Although Beebe and Barton did not get on well together, Barton confirmed the sighting in his own book, The World Beneath the Sea (1953). However, as he was busy maintaining the bathysphere at the time, Barton had missed seeing the dragonfish personally, something he deeply regretted.

“

... Dr. Beebe gave an exclamation. A deep sea dragon at least six feet long crossed before the window and a moment later returned with its mate. Until that time scientists had doubted the presence of such large fish in the middepths. This was the only big dragon on record, and I had missed seeing it!

”

However, Barton later claimed that he had indeed seen the dragonfish, although he got a much poorer look at it than Beebe, and was only able to describe it as strange-looking.

The audio of the 22 September dive was broadcast live on radio, on NBC and BBC. According to Barton, Beebe saw the dragonfish just as NBC was signing off; the sighting occurred shortly after Beebe and Barton began to ascend from their maximum depth of 2,200 ft (670 m), where the broadcast ended.

Theories

Bostelmann's technical drawing of the giant dragonfish.

Beebe believed the giant dragonfish could have been a relative of the common scaleless black dragonfishes (Melanostomias sp.) (Public Domain).

Beebe described the giant dragonfish as Bathysphaera intacta, a new genus and species in the family Stomiidae, related to the scaleless black dragonfish (Melanostomias bartonbeani). However, he admitted that this was a guess, and that the largest known dragonfish was only 15 in (38 cm) long, whereas this animal was at least 6 ft (1.8 m). As of 2017, the largest known dragonfish, the obese dragonfish (Opostomias micripnus), is just 1.8 ft (53 cm) long. Beebe thought it possible that Bathysphaera represented an entirely unknown dragonfish family. He had intended the specific name intacta to represent fact that the fish had been literally untouchable when he observed it, but Thomas Barbour (1884 – 1946) argued that intacta actually implied virginity, and therefore parthenogenetic reproduction. Beebe disagreed, but suggested Bathysphaera intangibilis as an alternate name.

Beebe was ordinarily wary of describing new species without extensive study of the animal's anatomy and behaviour. He claimed to have seen a wide variety of unknown fishes during the bathysphere dives, and was unwilling to attempt classification based on so little; however, knowing there would be no second chances to describe these fishes, he chose to assign taxonomic names to some of the most memorable and distinctive of them, with verification from Barton. The "type specimens" of these abyssal fishes were line drawings made by Else Bostelmann under Beebe's supervision, showing only characteristics of which he was certain; regarding the dragonfish specifically, Beebe stressed that he had observed them precisely enough for the illustrations to be accurate. The fishes he described were the giant dragonfish, pallid sailfin (Bathyembryx istiophasma), five-lined constellationfish (Bathysidus pentagrammus), and three-starred anglerfish (Bathyceratias trilynchus). He also informally described the abyssal rainbow gar. Although Barton had a camera, neither man was able to take photographs of the fishes. The bathysphere's low light was inadequate for photography, and a more powerful light introduced by Beebe had threatened to burst the window.

Due to the cirumstances of Beebe's observation, and the lack of either a physical holotype or any later sightings, the validity of Bathysphaera intacta has been challenged, and he has been accused of inventing some of his "abyssal fishes". Ichthyologist Carl Hubbs (1894 – 1979) took particular issue with the giant dragonfish, "the most notorious," arguing that each of the two giant fishes was really two smaller fish swimming very closely together, bearing a single bioluminescent tentacle. Despite his initial support, Barton himself, who clashed with Beebe following their dives, later described Beebe's description as "a little fishy [sounding] to me," particularly due to the lack of any later observations. Despite this, Bathysphaera intacta is still usually considered a valid species, and continues to appear in taxonomic lists.