Lithocarpus tapanuliensis (Fagaceae), a new stone oak from northern Sumatra and its role as an important resource for critically endangered orangutans

Study Extent

North Sumatra, Indonesia

Sampling

The collecting method for the dried specimens was referred to published procedures of preparing herbarium materials (Bridson and Forman,1992). The plant materials were collected and pressed in the field then mounted on an A2 paper after the specimens were dried. Before installation into the herbarium cabinets, the specimens were put into plastic bags. Every sheet of specimens was labeled with the standard information for herbarium collections, including taxonomic identification, locality information, geo-references, collector information, and ecological data. For insect control, we freeze the specimens periodically in -20 degrees Celsius freezer for 72 hours. All of the specimens were stored in the herbarium cabinets. The storage rooms were equipped with temperature and humidity control. All of the specimens were in alphabetical orders based on the families, grouped in several groups of plants, such as dicots, monocots, ferns, and mosses.

Quality Control

We divided our working groups into two groups: a) taxonomic determination or identification group and b) data geo-referencing group. For taxonomic determination, the identification was verified by experts on the designated taxa, and also was using book references for the taxa (Ashton, 1982; Van Der Meijden, 1984; Kalkman, 1993; Shaw, 1981). The experts are writers and researchers for the area of studies and have published using the materials at the Herbarium ANDA (Utami, 2006; Hughes, 2009, 2015, Hernawati, 2006). The datum references for each coordinate were collected from the specimen labels using the WGS84 standard. If the coordinate of the locations was not recorded on the labels, we used Google Map to obtain the coordinate based on the locality information of the villages recorded on the labels.

Method steps

1. The information on the specimen labels is our main data source. For data collection, we conducted in three steps: data capture, data cleaning, and data publication. In the data capture process, we collected all the information on the specimen’s label, and we input the information into Microsoft Excel spreadsheets using Darwin-Core format. In this process, we grouped the specimen information into three groups, consisting of data occurrence, taxon information, and event. We save the file in csv (comma-separated values) format. We included specimen photos and scanning data into the database incorporated in associateMedia field. All the images were stored in flickr-pro media, which then will link with the filed in the dataset. We conducted data cleaning to ensure consistency and standardized data input for the dataset. We used OpenRefine for batch error handling, Canadensys tools for coordinate conversion, and Splink for coordinate verification. To verify the taxonomic nomenclature, we used resolver, iPlant collaborative, ECAT, and POWO.

All of occurrences identified to species levels.

1. Lithocarpus tapanuliensis
   common name: Hoteng rank: species

During our fieldwork in Pilar Forest, a primary forest near the Bulu Mario District, we recorded two individuals of Lithocarpus tapanuliensis. The lower-montane forest is characterised by the abundance of meranti gunung (Shorea platyclados Slooten ex Endert). Sipirok Regency precipitation typically varies during different sections of the year. Maximum monthly precipitation is 296.5 mm and the minimum monthly precipitation is 67 mm, with an average temperature around 28 °C.