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💧 Freshwater Endangered 🌡️ Tropical

Gymnogeophagus Jaryi

Gymnogeophagus jaryi AlonsoTeránAguileraŘíčanCasciottaSerraAlmirónBenítez et al., 2019
Max Length
13.3 cm
Max Weight
Lifespan
Trophic Level
3.4
Depth
Climate
Tropical
Resilience
High
Vulnerability
20.00/100
Typical Length
Depth Zone

📖 Overview

Inhabits streams with sandy and rocky bottom and abundant marginal vegetation. The climate where it is found, on the mountain ridge in Aristóbulo del Valle, is classified as warm and temperate. In this area there is a significant rainfall throughout the year (average per year is 1,678 mm), and even in August with the lowest precipitation, it still has a considerable amount of rain (111 mm). The lowest precipitation occur from July to September, the driest period and lowest water levels from December to February due to the marked seasonal change in temperature, and peaks in precipitation occur from May and October. The annual average temperature is 19.1°C, with 23.9ºC monthly average temperature in January and 14.3ºC in June. Water level in the stream can have important changes: water turbidity is variable among the year with peaks of turbidity after rains and increases in water visibility the rest of the year. Specimens are frequently collected in the rocky areas or associated with marsh and marginal vegetation. The holotype was collected together with the female paratype under the marginal vegetation and with fry on November 2016 .

Scientific Name
Gymnogeophagus jaryi
Authority
AlonsoTeránAguileraŘíčanCasciottaSerraAlmirónBenítez et al., 2019
Habitat
Freshwater
Climate
Tropical
IUCN Status
EN
Max Length
13.3 cm
Trophic Level
3.4
Resilience
High
Vulnerability
20.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal spines (total): 13 - 14; Dorsal soft rays (total): 10 - 11; Anal spines: 3; Anal soft rays: 8 - 9. This species is distinguished from all its congeners except G. australis and G. caaguazuensis, by the presence of a hyaline to grey anterior portion of the dorsal fin; differs from caaguazuensis by having a longer caudal peduncle, caudal fin not lyrate, central portion of scales on dorsal part of trunk light iridescent blue and white spots in soft portion of dorsal fin in adult males; differs from australis by the light iridescent blue coloration of central area of scales on the dorsal portion of trunk and tail, and by the absence of scales on the soft portion of the dorsal fin. It is further distinguished by the following unique set of characters: D 10-11 branched rays; 27-30 E1 scales; absence of lips thickening; adult males with a hump, with large white spots forming transversal stripes distally and in anterior area of the dorsal fin’s soft portion, absence of a conspicuous and oblique dark band from the eye to the anterior border of the head, anterior part of dorsal fin hyaline to grey, scales of the midlateral spot each bearing a semicircular light blue blotch, the head hump start at the horizontal through the eyes, concave anterior profile in lateral view, base of unpaired fins yellow, and whitish hyaline spots on caudal fin .Cross section: compressed.

🌀 Behaviour

Behavioural data for Gymnogeophagus Jaryi is currently being reviewed.

🦐 Diet

Diet information for Gymnogeophagus Jaryi is currently being compiled.

🥚 Reproduction

Reproduction data for Gymnogeophagus Jaryi is currently being compiled.

🌍 Habitat & Distribution

Freshwater; benthopelagic. Tropical South America: Argentina and Paraguay.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
3.4±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.01995 × L3.01 (TL)
Max TL
13.3cm
Dorsal Spines
14
Dorsal Rays
11
Anal Spines
3
Anal Rays
9

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Endangered
Assessment Date
2020

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
20.00/100
Low vulnerability
Trophic Level
3.4
Predator
Climate Zone
Tropical
Described By
AlonsoTeránAguileraŘíčanCasciottaSerraAlmirónBenítez et al., 2019

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