Wilson Novarino

Sex determination by DNA-based molecular techniques in Sumatran tigers needs to be investigated and developed for forensic and population genetic purposes. The amelogenin gene is a marker commonly used for sex determination. In some species, the difference between the AMELX and AMELY sequences has been reported to be in the intron region. However, the difference between the AMELX and AMELY sequences in the Sumatran tiger is unknown. Therefore, it is necessary to investigate the sequence differences in introns between AMELX and AMELY Sumatran tigers to determine the specific differences between male and female samples. This study aimed to analyse the sequence of nucleotide bases in the Sumatran tiger amelogenin gene introns based on the nucleotide base sequences in the amelogenin gene introns. The method in this research is descriptive, with a molecular observation of the AMELX and AMELY Sumatran tiger sequences. The amplified samples were sequenced, and it was found that the lengths of the AMELX and AMELY Sumatran tiger sequences were 215 bp and 194 bp, respectively, with a 21 bp deletion in the AMELY sequence.

In this comprehensive study, we examined 15 distinct morphometric characteristics within seven Indonesian hornbill species. Precise measurements of these morphometric traits were obtained using 0.1 mm calipers and a 1000 mm measuring tape. Our analysis encompassed a total of 85 individuals representing seven hornbill species: Anthracoceros albirostris (18 individuals), A. malayanus (4 individuals), Aceros cassidix (3 individuals), Rhyticeros plicatus (7 individuals), R. undulatus (36 individuals), Buceros bicornis (1 individual), and B. rhinoceros (16 individuals). To elucidate the morphometric ratio data, we employed a robust analytical approach involving the Principal Component Analysis (PCA), Discriminant Analysis, and Cluster Analysis. Our findings underscored a clear separation between hornbill genera, primarily attributed to a combination of PC1 (pertaining to body length) and PC3 (associated with beak morphology). Key morphometric traits that delineated these genera on PC1 included tail length, beak length, horn length, total length, and wing length. Meanwhile, on PC3 (characterizing beak morphology), the distinguishing features encompassed beak width, horn width, and tarsus length. Additionally, our analysis unveiled the characteristics that distinguish species within the genera Anthracoceros and Rhyticeros to be a composite of tail length and head length. This discerning morphometric data facilitated the clustering of seven hornbill species into two distinct groups: Group I comprised A. albirostris and A. malayanus, while Group II included R. plicatus, R. undulatus, A. cassidix, B. rhinoceros, and B. bicornis. Notably, these groups exhibited a 31.93% degree of similarity. This dataset holds immense potential for facilitating genetic classification and comparative studies of Indonesian hornbills.

Trypanosoma in Central Sulawesi mammals

Black-and-white langur Presbytis bicolor Aimi & Bakar, 1992 is a rare endemic leaf-eating monkey that occurs only in a limited distribution between the Indragiri River and Batanghari River, Sumatra, Indonesia. In this paper, we summarize historical records of P. bicolor, put the distribution records into the map (including new localities, but still in geographic range), and provide new additional pieces of information on its ecology. We collected all published and unpublished of our observations on P. bicolor from January 2016 to April 2022. Our findings suggest P. bicolor can tolerate and survive in the degraded forest habitat, particularly in areas where rubber plantations are present. It was confirmed that P. bicolor fed leaves of Para rubber tree Hevea brasiliensis (Euphorbiaceae) and Mango Mangifera sp (Anacardiaceae); and it was reported that they also fed various plants. No indications of hunting or illegal collecting for the pet trade, but the mortality due to electrocution from power lines and road accidents have been detected and confirmed for this species.