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🌊 Marine Least Concern 🌡️ Tropical

Blackmargin rockskipper

Praealticus caesius Seale, 1906
Max Length
7.9 cm
Max Weight
-
Lifespan
-
Trophic Level
2
Depth
-
Climate
Tropical
Resilience
High
Vulnerability
20.00/100
Typical Length
-
Depth Zone
pelagic

📖 Overview

Facultative air-breathing ; Adults are found in tidepools . Oviparous. Eggs are demersal and adhesive , and are attached to the substrate via a filamentous, adhesive pad or pedestal . Larvae are planktonic, often found in shallow, coastal waters .

Scientific Name
Praealticus caesius
Authority
Seale, 1906
Habitat
Marine
Climate
Tropical
Body Shape
Elongated
IUCN Status
LC
Max Length
7.9 cm
Trophic Level
2
Resilience
High
Vulnerability
20.00/100
Salinity
30–40 ppt

🐟 Physical Description

Dorsal spines (total): 13; Dorsal soft rays (total): 17 - 20; Anal spines: 2; Anal soft rays: 19 - 22. Lip margins smooth; females dorsally whitish to light gray and ventrally white with a series of 6 paired black spots (anterior 2 pairs irregular with a row of spots above) on upper side of body, and 1 spot on caudal peduncle, each connected by a gray bar to a lower series; a black line on back at spinous portion of dorsal fin, and 4 pairs of small black spots along base of soft portion; small bluish white spots on posterior half of body, mostly on upper half; narrow black bars ventrally on head angling on to throat; a white line at posterior edge of eye continuing below to upper lip; median fins with blackish margins; posterior part of crest with a narrow pink margin and a broad, submarginal black band; dorsal-fin base with alternating black and whitish blotches; a black spot at midbase of caudal fin; males similar except with darker body; bluish white spots on body generally elliptical; faint oblique black bands on throat; oblique white lines in soft portion of dorsal fin. Last spine of dorsal fin very small; dorsal soft rays usually 19; anal soft ray rarely 19 or 22; middle 6-9 of 14 segmented caudal rays branched; lateral-line pores 5-9 .: elongated.

🌀 Behaviour

Behavioural data for Blackmargin rockskipper is currently being reviewed.

🦐 Diet

Diet information for Blackmargin rockskipper is currently being compiled.

🥚 Reproduction

🐣 Oviparous

Oviparous, distinct pairing .

🌍 Habitat & Distribution

Marine; pelagic-neritic. Tropical; 21°S - 24°S, 176°W - 128°W Central Pacific.

🌿 Ecology

Zone Preferences
🌊 Marine 🐟 Pelagic
Trophic Level
2

📐 Morphometrics

Length–Weight Relationship: W = 0.00759 × L3 (TL)
Max TL
7.9cm
Dorsal Spines
13
Dorsal Rays
19
Anal Spines
2
Anal Rays
21

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2009

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
20.00/100
Low vulnerability
Trophic Level
2
Omnivore / Planktivore
Body Shape
Elongated
Climate Zone
Tropical
Described By
Seale, 1906

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