Radular Morphology of Thiarid from Raja Ampat

Radula in gastropods is considered as a constant and conservative character that can be used in classification and phylogenetic at certain taxa level. However, character of radula is also ecophenotypic, so that the morphology of the radula can also indicates intraspecific variations that able to detect differences among species. The insights of the radular morphology specific to Thiaridae is important for classifying species within this family. Through an enzymatic procedure using the proteinase-K, five radula of Thiarid from Raja Ampat were extracted. The results of research on radula showed that the five species studied had the taeniglossan radula type. The band of the radula is 1.8 - 4.8 mm long and consists of marginal teeth, lateral teeth, and rachidian. The radula formula is 2/1/R/1/2 with a 3-4/1/3-4 rachidian pattern and a 2-3/1/2-3 lateral teeth pattern. The mesocone shape of the rachidian and lateral teeth varies between rounded and pointed.

Front Matter

Front Matter

Mercury Content on Mangrove Roots and Telescopium telescopium in Kao Bay, North Halmahera

The process of extracting gold using mercury (Hg) carried out by Nusa Halmahera Minerals industries (PT. NHM) as well as by the community of illegal gold mining or gold mining without a permit (PETI) that occurs in the mining area of ​​Halmahera Island can have a negative impact on the aquatic environment. This study aims to determine the mercury absorption in mangrove roots of Rhizopora sp and Telescopium telescopium at two different stations. Sampling of mangrove roots was repeated 3 times for each station. Differences in the accumulation of heavy metals Hg in the roots of Rhizophora sp were analyzed using the T-test. The study showed that the concentration of mercury in the roots of Rhizophora sp ranged from 0.016 – 0.026 mg/kg and there were differences in root absorption between Rhizopora sp at station 1 of the Tabobo River mangrove near the PETI disposal and station 2 at the mining industry waste disposal. The concentration of mercury in Telescopium telescopium ranged from 0.08 - 0.15 mg/kg. It is indicates that Telescopium telescopium in Kao Teluk has been contaminated with mercury but is still below the threshold of the quality standard that has been set.

Back Matter

Back Matter

Production and Biomass of Pokea Clam (Batissa violacea var. celebensis von Martens, 1897) in the Langkumbe River Waters North Buton Southeast Sulawesi

Langkumbe River is located in West Kulisusu District and has long been used by the community for various daily activities. One of the resources often used by the people around Langkumbe River is pokea clams. The aim of this study was to determine the production and biomass of pokea clams (B. violacea) in Langkumbe River Waters of North Buton Regency from August to October 2017. The sampling method used was swept area method using a traditional fishing gear "Tangge" (fishing gear). The samples were measured for the length, width and thickness. The total weight was measured with the clam/total mass (MT) and the weight of the meat. The samples were dried using an oven for 24 hours at 70 °C to obtain the shell-free dry mass (SFDW). Data were analyzed using standard formulas. The total sample obtained was 1.307 individuals. The highest density of pokea clam was found in August at 596.8 ind/m². Annual production of pokea clam (B. violacea) in Langkumbe River with a total annual production of 1,107.33 gSFDW/m2/year. The highest and lowest production are 297.09 gSFDW/m²/year at size 2.19-2.54cm and -0.16 gSFDW /m²/year at size 4.70-5.05cm, respectively. The total population biomass was 528.03 gSFDW/m2 with the highest biomass 171.72 gSFDW/m²/year at size 2.55-2.90 cm and the lowest was 1.40 gSFDW /m²/year at size 4.70-5.05 cm, so that the recovery rate (P/B ratio) was 2.1 gSFDW/m2/year.

Identification of Molluscan Animal Image in Two-Dimensional Print Media

Humans have known mollusks for a long time. The diverse and unique shell shapes are interesting to draw. The easiest medium to describe the shape of a mollusk is in two dimensions. This study aims to identify various images of mollusks in two-dimensional print media such as cloth, paper and plates. Based on the 10 sources of photos analyzed, 56 species of mollusks from 38 families were identified. The Gastropod class dominates with 45 species from 31 families, followed by Bivalves with 7 species from 5 families, then Cephalopods with 4 species from 2 families. Some of the problems found are the shape and proportion of images that different with specimens, some inverted or cropped images, different direction of rotation of the shells with specimens, and different colour patterns with specimens. Biological and distributional aspects of several families will be discussed briefly in this paper.

Reconstruction of Light Organ in Squid With The Histological Method of Electron Transmission Microscope

The light organ is an electronic device that can emit light. However, there are light organs in animals that can produce light naturally. Loligo duvaucelii is a species whose biolumenesence comes from fluorescent bacteria that live in symbiosis in its ink sacs. This study aims to determine in detail the construction of the squid light organ using the transmission electron microscopy (TEM) method. The results showed that this type of squid has a pair of light organs attached to the dorso-lateral ink sac. The light organ is spherical, some are found on the surface and some are embedded on the wall of the ink sac. It consists of a lens that is located on the outer surface of the ink sac, and a sac of light organs (embedded on the wall of the ink sac) with channels connecting the pocket to the mantle cavity. The wall of the sac of the light organ consists of three layers, namely the innermost layer which is multi-fold with microvilli on the cell surface and between the folds of the sac populated with bacteria, the dense layer that acts as a reflector, and the pigment layer. Cilia are observed on the surface of the duct connecting the sac with the mantle cavity. This study concluded that the construction of the squid light organ has a convex-shaped lens structure and is muscular. In the pockets of light organs, a dense population of bacteria is found. The reflector consists of many layers, and the pigment layer contains many granules.

Front Matter

Jurnal Moluska Indonesia (JMI) merupakan jurnal yang diterbitkan oleh Masyarakat Moluska Indonesia. Jurnal ini terbentuk oleh inisiatif masyarakat moluska indonesia yag terdiri dari dosen, peneliti, mahasiswa, praktisi, dan stakeholders pada tanggal 17 April 2020 di Kota Bogor, Jawa Barat. Jurnal Moluska Indonesia (JMI) mempunyai ruang lingkup meliputi ekologi, konservasi dan biodiversitas, budidaya, sosial budaya, penangkapan, dan mikrobioteknologi. Waktu publikasi Jurnal Moluska Indonesia (JMI) pada April dan Oktober. Harapan dan ekspektasi yang tinggi terkait Jurnal Moluska Indonesia ini dapat digunakan sebagai acuan, pedoman, inventarisasi keanekaragaman, dan pengelolaan sumber daya Moluska di Indonesia

Keanekaragaman dan Kemelimpahan Nudibranchia di Perairan Tulamben, Bali

Nudibranchia is the largest order of Opistobranchia which is known to have about 3,000 species. Nudibranchia is a popular macro photography object among divers. Although Tulamben Waters, Bali is one of popular destination for macrobiota’s habitat, but research on marine biota, especially nudibranchia in these waters is still very rare. This study uses two methods, which is direct observation to reveal diversity and species number, belt transect methods to estimate density or abundance per sampling area using diving techniques . A transect line of 50 m at each point of observation site was used to evaluate abundance. This study wants to see the level of diversity, mapping various species and abundance of nudibranchia. For biodiversity, 31 species from 15 families are found, Chromodoridae, Dorididae, Elysiidae, Facelinidae, Flabellinidae, Goniodorididae, Halgerdidae, Hexabranchidae, Phyllidiidae Polyceridae, Hydatinidae, Costasiellidae, Elysiidae and Limapontiidae. Whereas the transect method found 12 species from 6 families, Chromodoridae, Facelinidae, Phyllidiidae Aglajidae, Costasiellidae, and Elysiidae. With a diversity index of 2.27 and the highest level of abundance found in Pteraeolidia ianthina species with a relative abundance of 0.19%.

Front Matter

PEDOMAN PENULISAN Jurnal Moluska Indonesia (JMI)