Reproductive biology of the tiger pleco Panaqolus tankei (Loricariidae) in a lentic system of the Amazon Basin

Abstract

This study presents the first information on the reproduction of the recently described tiger pleco Panaqolus tankei, from Lake Bolonha in the north-eastern Amazon Basin. This loricariid has a long reproductive period, fractionated spawning and low fecundity (on average, female gonads contained 37 oocytes), a total length (L ) at first maturity of 47.4 mm for females and 54.1 mm L for males. Correlation of the condition factor and gonado-somatic index with environmental variables suggests that turbidity favours P. tankei reproduction in this environment.

Evidence of secondary sexual dimorphism in King Tiger Plecos Hypancistrus sp, Loricariidae, of the Amazon River basin

“…Similar results were observed in Baryancistrus xanthellus , Peckoltia oligospila and Hypancistrus zebra (Viana et al, 2022), in Hypostomus garmani (Moreira et al, 2020) and in Pterygoplichthys disjunctivus (Jumawan & Herrera, 2015) all belonging to the Loricariidae family. In females, all oocyte types were similar to those found in loricariids (Brysiewicz et al, 2011; Mendes et al, 2018; Viana et al, 2018), in addition to the presence of a post‐ovulatory follicle that indicates that spawning has occurred (Cardim et al, 2019).…”

“…In females, all oocyte types were similar to those found in loricariids (Brysiewicz et al, 2011;Mendes et al, 2018;Viana et al, 2018), in addition to the presence of a post-ovulatory follicle that indicates that spawning has occurred (Cardim et al, 2019).…”

“…Despite the smaller size of females, all of them had larger bellies than the males, regardless of sexual stage. Although this characteristic has never been reported, it is common for loricariids to have large volumes of mature oocytes as seen in Panaqolus tankei that produced an average of 37 oocytes with a diameter of 2.87 mm (Mendes et al, 2018), in H. zebra where mature oocytes had an average diameter of 4.87 mm (Viana et al, 2018) and in Hypancistrus sp. (Sousa et al, 2021) which had an average diameter of 2.0 mm and an oocyte production that ranged from 34 to 55 per spawning.…”

Reproductive cycle of the tetra Astyanax bimaculatus (Characiformes: Characidae) collected in Amazonian streams

“…Histology has been used to study reproduction in many fish species such as the tetra Astyanax altiparanae (Rodrigues et al, 2015;Cassel et al, 2017), the Danio Devario aequipinnatus (Chagas et al, 2016; De Jesus-Silva et al, 2018) and some Amazonian species including the Amazonian whitefish Plagioscion squamosissimus (Barbosa et al, 2012) and the 'piranha' Serrasalmus gouldingi (Da Silveira Prudente et al, 2014). This tool is considered one of the most accurate approaches for analyzing reproductive development as it allows the determination of reproductive phases in males and females, defining, for example, time of first maturation, spawning type, reproductive period (Vazzoler, 1996) and fecundity (Mendes et al, 2018).…”

Follicular complex may predict reproductive tactics in siluriform fishes

“…Teleost fish have different reproductive tactics, for example, migration [ [1] , [2] , [3] ], different types of spawning [ [4] , [5] , [6] ], parental care that occurs in different ways such as the storage of fertilized eggs in the mouth [ [7] , [8] , [9] ], the construction of nests and the maintenance of continuous aeration of the eggs [ [10] , [11] , [12] ]. In females, mature oocytes indicate some reproductive tactics such as the reproductive period [ 13 , 14 ] and type of spawning [ 15 , 16 ], and the animal's fecundity can be estimated [ 5 , 17 , 18 ].…”