National Research and Innovation Agency, Research Center for Biosystematics and Evolution, Museum Zoologicum Bogoriense, Cibinong, Indonesia.
National Research and Innovation Agency, Research Center for Limnology and Water Resources, Cibinong, Indonesia.
Braz J Biol. 2024 Feb 26;84:e279429. doi: 10.1590/1519-6984.279429. eCollection 2024.
Cichlid fishes exhibit rapid adaptive radiations with significant diversification rates in response to ecological variability, i.e., ecological opportunity or geographical isolation. The discovery of a Midas cichlid species in Lake Batur, Indonesia's largest volcanic lake, first reported in 2013, could represent such adaptations. Midas cichlids can now be found in a range of habitats in Lake Batur and dominate the lake's fish population by up to 60%. This study aimed to identify the interaction between habitat, water quality, and Midas cichlid in Lake Batur, facilitating morphometric variances in the fish populations. The fish were captured at five locations in Lake Batur using fishing rods, community nets with mesh sizes of 2-3 inches, experimental gillnets with mesh sizes of 1 inch, and fish scoops in floating net cages during August and November 2022. There were 46 fish samples caught from the five stations, all photographed using a digital camera and later measured using the ZEN 2012 software. The fish measurement employed a truss morphometric method using 21 distinct morphometric body features. Canonical analysis was used to determine the distribution of characteristics, while discriminant analysis was used to examine the closeness of association. The measured water quality parameters included pH, DO, temperature, conductivity, and TDS for in-situ and TSS, TP, TN, and chlorophyll A for ex-situ. The findings revealed morphometric changes among Midas cichlid species in Lake Batur caused by habitat and water quality differences. The distinction can be detected in the anterior and posterior bodies (C1, B1, C3, C6, C5, B3 and B4). Temperature and aquatic plants, Azolla pinnata, may detect the station and shape of fish in Lake Batur. Body shape cannot be identified by chlorophyll A, TN, DO, and TDS. Future genetic research could answer why fish groups with varied body types coexist in the same location.
慈鲷鱼表现出快速的适应性辐射，对生态变异性（即生态机会或地理隔离）具有显著的多样化速率。2013 年首次报道的在印度尼西亚最大的火山湖——巴图尔湖发现的一种金头丽鱼物种，可能代表了这种适应。金头丽鱼现在可以在巴图尔湖的一系列栖息地中找到，其数量占该湖鱼类总数的 60%。本研究旨在确定巴图尔湖中栖息地、水质和金头丽鱼之间的相互作用，从而促进鱼类种群的形态差异。2022 年 8 月和 11 月，使用钓鱼竿、网目尺寸为 2-3 英寸的社区网、网目尺寸为 1 英寸的实验刺网和漂浮网笼中的捞鱼器在巴图尔湖的五个地点捕获鱼类。从五个站位捕获了 46 个鱼类样本，所有样本都使用数码相机拍照，然后使用 ZEN 2012 软件进行测量。鱼类测量采用 21 个不同形态学身体特征的桁架形态测量法。典型分析用于确定特征的分布，而判别分析用于检查关联的接近程度。测量的水质参数包括现场的 pH、DO、温度、电导率和 TDS 以及现场外的 TSS、TP、TN 和叶绿素 A。研究结果表明，由于栖息地和水质差异，巴图尔湖中金头丽鱼物种的形态发生了变化。可以在身体的前部和后部（C1、B1、C3、C6、C5、B3 和 B4）发现差异。温度和水生植物，满江红，可能可以检测到巴图尔湖的站位和鱼类形状。而叶绿素 A、TN、DO 和 TDS 无法识别鱼体形状。未来的遗传研究可以回答为什么具有不同体型的鱼类群体可以在同一地点共存。
