Kkmb kota tarakan merupakan salah satu daerah yang memiliki keanekaragaman jenis spesies baik biota aquatik maupun biota teresterial. jenis spesies akuatik di kkmb kota tarakan salah satunya kerang kapah (geloina coaxans). tujuan penelitian adalah untuk mendapatkan sifat pertumbuhan alometri dan indeks kondisi kerang kapah di kkmb kota tarakan. metode penelitian menggunakan metode penelitian deskriptif kuantitatif. penentuan lokasi menggunakan metode purposive sampling di daerah perluasan kkmb kota tarakan sebanyak 12 transek dengan ukuran 10x10 meter. teknik pengumpulan data menggunakan desain penelitian survei dan skala laboratorium. hasil penelitian didapatkan sebanyak 316 individu kerang kapah, sehingga di dapatkan hasil mengenai hubungan panjang dan berat antara dimensi cangkang (panjang, tinggi, dan tebal) dengan berat kering daging yaitu bersifat allometri negatif. hasil penelitian mengenai indeks kondisi didapatkan persentase keseluruhan yakni bentuk tubuh kurus sebesar 54,11%, bentuk tubuh proporsional (ideal) sebesar 39,24% dan bentuk tubuh gemuk sebesar 6,65%. habitat kerang geloina coaxans di daerah kkmb 12 ha yaitu nilai rata-rata salinitas sebesar 26,5 ± 1,5 ppt ; ph sebesar 7,33 ± 0,33 ; dan suhu sebesar 28 ± 1oc. kata kunci: kerang kapah; geloina coaxans; sifat pertumbuhan; indeks kondisi; kkmb tarakan

Kkmb kota tarakan is one of the areas that have diversity of species species both aquatic biota and terrestrial biota. the aquatic species in kkmb kota tarakan one of the shellfish (geloina coaxans). the aim of this research is to get the growth characteristic of alometry and condition index of shellfish at kkmb kota tarakan. a quantitative descriptive method was used in this research which locating determination used purposive sampling in the kkmb expansion area of tarakan applying 12 transects with its size 10x10 meters. in collecting the data, the researcher used survey research design and laboratory scale the result of this research is 316 individual shellfish, so we get the result of the long and heavy relationship between the dimensions of the shell (length, height, and thickness) with the dry weight of the meat is allometri negative. the results of research on the condition index obtained the overall percentage of the form of a thin body of 54.11%, body shape proportional (ideal) of 39.24% and body shape of fat 6.65%. kepah clam habitat in kkmb was 12 hectare with average salinity 26,5 ± 1.5 ppt ; ph of 7,33 ± 0.33 ; and temperature around 28 ± 1oc. keywords: kepah clam; geloina coaxans; growth; condition index; tarakan kkmb