PARAPRIACANTHUS RANSONNETI - (STEINDACHNER, 1870)
Actinopterygii (Gigaclass) > Actinopteri (Class) > Teleostei (Subclass) > Acropomatiformes (Order) > Pempheridae (Family) > Parapriacanthus (Genus)
Poisson hachette nain, Poisson hachette jaune, Poisson-harpe doré, Golden bullseye, Golden sweeper, Pigmy sweeper, Ransonnet's bullseye, Rosy sweep, Slender sweeper, Yellow sweeper, Slank veër, Igelilanibaiu, Pygmæfejer, Indischer Glasfisch, Schlanker-Beibauchfische, Kinmemodoki, キンメモドキ, 充金眼鯛, 황안어,
Synonymes
Parapriacanthus beryciformis (Franz, 1910)
Parapriacanthus ransonnari (Steindachner, 1870)
Parapriacanthus unwini (Ogilby, 1889)
Poisson hachette nain, Poisson hachette jaune, Poisson-harpe doré, Golden bullseye, Golden sweeper, Pigmy sweeper, Ransonnet's bullseye, Rosy sweep, Slender sweeper, Yellow sweeper, Slank veër, Igelilanibaiu, Pygmæfejer, Indischer Glasfisch, Schlanker-Beibauchfische, Kinmemodoki, キンメモドキ, 充金眼鯛, 황안어,
Synonymes
Parapriacanthus beryciformis (Franz, 1910)
Parapriacanthus ransonnari (Steindachner, 1870)
Parapriacanthus unwini (Ogilby, 1889)
Pempheris unwini (Ogilby, 1889)
--------------------------
Description
Dorsal spines (total): 5-6 (usally: 5); Anal soft rays: 18-23 (usually: 19-20); Pectoral fin rays: 16; Gill rakers: 26; Body Depth: 2.9-3.3 in SL; Lateral line scales: 60-79 (usually: 62-75); Head length: 2.9-3.1 in SL; Eye diameter: 6.6-7.4 in SL; Predorsal length: 2.3-2.4 in SL; Pectoral fin length: 3.3-3.45 in SL. Body with 1 or 1.5 scales rows between coracoid and midlateral edge of coracoid and midlateral edge of pelvic bone. Caudal fin forked. Max. length: 10.0 cm TL. Depth range: 2 - 30 m.
Color
Iris gold and green in color; A horizontal blackish streak beginning dorsally on the opercle and disappearing below the posterior end of the dorsal fin. Recognised by having preanal pin-like mark (a distinct black line, shaped like a pin, within a white band, midventrally just before the anus). Fins pink, caudal tips and scale margins black. A vertical blackish line at caudal fin base.
Etymology
Parapriacanthus: from Greek, para = near + from Greek, prion = saw + from Greek, akantha = thorn. Refers to the thorny scales that cover the body and head of these species.
ransonneti: in honnor of Baron Eugen Freiherr von Ransonnet-Villez (1838-1926), German consul at Singapore, which made a collection which the eminent Franz Steindachner reported upon in 1870.
Original description: Parapriacanthus ransonneti Steindachner, 1870 - Type locality: Nagasaki, Japan.
Distribution
Biology
Found in coastal and offshore reefs. This species forms large groups in caves under ledges or beneath overhangs in reef (under Acropora plate corals). Individuals forage at night, on zooplankton (mainly crustacean larvae and polychaetes. In 2020, French biologists managed to reproduce this species in an aquarium.
Parapriacanthus has two types of ventral light organs: a Y-shaped thoracic light organ, which extends from the first pair of pyloric caeca and is located from the isthmus to the base of the pelvic fins beneath the thoracic translucent muscle, and a linear anal light organ, which emerges from the rectum and anus. Individuals use the ventral bioluminescence to hide their silhouette (counterillumination).
Researchers discovered that Parapriacanthis ransonnetti obtains not only its luciferin but also its luciferase enzyme from their bioluminescent ostracod prey. The enzyme purified from the fish’s light organs was identical to the luciferase of Cypridina noctiluca, a bioluminescent ostracod (Bessho-Uehara et al. 2020).
Similar species
--------------------------
Description
Dorsal spines (total): 5-6 (usally: 5); Anal soft rays: 18-23 (usually: 19-20); Pectoral fin rays: 16; Gill rakers: 26; Body Depth: 2.9-3.3 in SL; Lateral line scales: 60-79 (usually: 62-75); Head length: 2.9-3.1 in SL; Eye diameter: 6.6-7.4 in SL; Predorsal length: 2.3-2.4 in SL; Pectoral fin length: 3.3-3.45 in SL. Body with 1 or 1.5 scales rows between coracoid and midlateral edge of coracoid and midlateral edge of pelvic bone. Caudal fin forked. Max. length: 10.0 cm TL. Depth range: 2 - 30 m.
Color
Iris gold and green in color; A horizontal blackish streak beginning dorsally on the opercle and disappearing below the posterior end of the dorsal fin. Recognised by having preanal pin-like mark (a distinct black line, shaped like a pin, within a white band, midventrally just before the anus). Fins pink, caudal tips and scale margins black. A vertical blackish line at caudal fin base.
Etymology
Parapriacanthus: from Greek, para = near + from Greek, prion = saw + from Greek, akantha = thorn. Refers to the thorny scales that cover the body and head of these species.
ransonneti: in honnor of Baron Eugen Freiherr von Ransonnet-Villez (1838-1926), German consul at Singapore, which made a collection which the eminent Franz Steindachner reported upon in 1870.
Original description: Parapriacanthus ransonneti Steindachner, 1870 - Type locality: Nagasaki, Japan.
Distribution
Eastern Indian Ocean; Western Pacific: Indonesia, east to Marshall Islands and Fiji, north to southern Sea of Japan and Ogasawara Islands, south to Western Australia, Lord Howe Island and New Caledonia.
Biology
Found in coastal and offshore reefs. This species forms large groups in caves under ledges or beneath overhangs in reef (under Acropora plate corals). Individuals forage at night, on zooplankton (mainly crustacean larvae and polychaetes. In 2020, French biologists managed to reproduce this species in an aquarium.
Parapriacanthus has two types of ventral light organs: a Y-shaped thoracic light organ, which extends from the first pair of pyloric caeca and is located from the isthmus to the base of the pelvic fins beneath the thoracic translucent muscle, and a linear anal light organ, which emerges from the rectum and anus. Individuals use the ventral bioluminescence to hide their silhouette (counterillumination).
Researchers discovered that Parapriacanthis ransonnetti obtains not only its luciferin but also its luciferase enzyme from their bioluminescent ostracod prey. The enzyme purified from the fish’s light organs was identical to the luciferase of Cypridina noctiluca, a bioluminescent ostracod (Bessho-Uehara et al. 2020).
Similar species
- Parapriacanthus argenteus (von Bonde, 1923) - Reported from Southwestern Indian Ocean: KwaZulu-Natal (South Africa) north to southern Mozambique. Dorsal spines (total): 6; Dorsal soft rays (total): 9; Anal spines: 3; Anal soft rays: 20-23. Black, pin-like mark, about half length of pelvic fins, within a white band that encircles head of pin just anterior to anus (not present in juveniles).
- Parapriacanthus dispar (Herre, 1935) - Reported from New Caledonia and Loyalty Islands. Dorsal fin: 6 spines; Anal-fin: 21-25 soft rays; Lateral line scales: 54-64 (usually: 56-61); Dorsal fin: 6 spines (sometimes: 5); Anal fin: 22-24 soft rays (usually: 23); Deeper-bodied, with 2 or more scales rows between midventral edge of coracoid and midlateral edge of pelvic bone.
- Parapriacanthus guentheri (Klunzinger, 1871) - Reported from Red Sea; Northwestern Indian Ocean: Socotra (Yemen).
- Parapriacanthus marei (Fourmanoir, 1971) - Reported from New Caledonia and Loyalty Islands. Dorsal fin: 6 spines; Anal fin: 26-28 soft rays; First gill arch with 7-8 gill rakers on upper limb, 19-22 on lower limb.
Last update: 31, May 2024