Electronic Theses and Dissertation

Ikan Osteochilus spp. merupakan salah satu ikan yang banyak tersebar di provinsi Aceh. Banyak sebutan lokal untuk ikan Osteochilus spp. sehingga banyak kesalahan dalam mengidentifikasi spesies. Informasi ikan Osteochilus spp. dalam intra-spesies sangat kurang dalam proses identifikasi. Karakteristik morfologi yang hampir sama dapat menimbulkan kekeliruan dalam proses identifikasi spesies. Penelitian ini bertujuan untuk menganalisis keragaman spesies genus Osteochilus di hulu DAS Peusangan dan Seunagan dengan pendekatan studi morfometrik dan meristik. Penelitian dilakukan sejak Agustus 2022 sampai Februari 2023 dengan tiga titik pengambilan sampel (stasiun), antara lain Danau Laut Tawar dan Sungai Peusangan yang mewakili DAS Peusangan serta Sungai Seunagan yang mewakili DAS Seunagan, Pengambilan sampel ikan Osteochilus spp. menggunakan metode pengambilan acak sederhana. Pengukuran morfometrik dan meristik dilakukan di Laboratorium Dinas Perikanan Kabupaten Aceh Tengah dan Laboratorium Genetik dan Biodiversitas Akuatik, Fakultas Kelautan dan Perikanan, Universitas Syiah Kuala. Pengukuran morfometrik menggunakan metode tradisional terhadap 25 parameter ukuran, sedangkan pengukuran meristik dilakukan terhadap 12 parameter ukuran. Data pengukuran morfometrik dianalisis menggunakan Discriminant Function Analysis (DFA) untuk mendiskriminankan atau mengelompokkan populasi, sedangkan data pengukuran meristik dianalisis secara deskriptif. Hasil analisis multi-variasi menghasilkan dua fungsi. Fungsi pertama mengelompokkan ikan Osteochilus spp. di Danau Laut Tawar dan Sungai Peusangan sebagai populasi yang sama. Fungsi kedua menunjukkan populasi ikan Osteochilus spp. Sungai Seunagan sebagai populasi terpisah. Hasil analisis karakter meristik menunjukkan bahwa ikan Osteochilus di Danau Laut Tawar dan Sungai Peusangan cenderung merujuk pada spesies yang sama, sedangkan ikan Osteochilus di Sungai Seunagan cenderung merujuk pada spesies yang berbeda dengan stasiun lainnya. Hasil analisis hubungan panjang dan berat menunjukkan pola pertumbuhan ikan Osteochilus spp. di Danau Laut Tawar dan Sungai Seunagan bersifat allometrik negatif, sedangkan Sungai Peusangan menunjukkan pola pertumbuhan isometrik. Ikan genus Osteochilus di DAS Peusangan dan Seunagan diduga terdiri dari lebih dari satu spesies. Perhitungan hubungan panjang dan berat ikan Osteochilus spp. di DAS Peusangan dan Seunagan kurang berperan dalam proses identifikasi, karena pertumbuhan lebih dominan dipengaruhi faktor eksternal.

Kata kunci: morfometrik, meristik, Osteochilus, DAS Peusangan, DAS Seunagan

Fish Osteochilus spp. is one of the many scattered fish in the province of Aceh. Many local names for fish Osteochilus spp. so many mistakes in identifying the species. Information fish Osteochilus spp. in intra-species is very lacking in the identification process. Almost the same morphological characteristics can lead to confusion in the species identification process. This study aims to analyze the diversity of species of the genus Osteochilus in the headwaters of the Peusangan and Seunagan watersheds using a morphometric and meristic study approach. The research was conducted from August 2022 to February 2023 with three sampling stations, including Lake Laut Tawar and Peusangan River which represents the Peusangan Watershed and Seunagan River which represents the Seunagan Watershed. Sampling of Osteochilus spp. using a simple random sampling method. Morphometric and meristic measurements were carried out at the Central Aceh District Fisheries Service Laboratory and the Laboratory of Aquatic Genetics and Biodiversity, Faculty of Marine and Fisheries, Syiah Kuala University. Morphometric measurements used traditional methods for 25 size parameters, while meristic measurements were carried out for 12 size parameters. Morphometric measurement data were analyzed using Discriminant Function Analysis (DFA) to discriminate or classify the population, while meristic measurement data were analyzed descriptively. The results of the multi-variate analysis produce two functions. The first function is to classify Osteochilus spp. in Lake Laut Tawar and Peusangan River as the same population. The second function shows the population of Osteochilus spp. Seunagan River is a separate population. The results of the meristic character analysis showed that the Osteochilus fish in Lake Laut Tawar and Peusangan River tended to refer to the same species, while the Osteochilus fish in the Seunagan River tended to refer to different species from other stations. The results of the analysis of the relationship between length and weight showed the growth pattern of Osteochilus spp. in Lake Laut Tawar and Seunagan River is negative allometric, while Peusangan River shows an isometric growth pattern. Fish of the genus Osteochilus in the Peusangan and Seunagan watersheds are thought to consist of more than one species. Calculation of the relationship between length and weight of Osteochilus spp. in the Peusangan and Seunagan watersheds, they play less of a role in the identification process, because growth is more dominantly influenced by external factors. Keywords: morphometric, meristic, Osteochilus, Peusangan Watershed, Seunagan Watershed