Corresponding author: Menno Schilthuizen (
Academic editor: Yasen Mutafchiev
On a ‘taxon expedition’-style field course at Kuala Belalong Field Studies Centre in Brunei Darussalam (Borneo), a new species,
In this paper, we provide partial results from a taxon expedition to the Ulu Temburong rainforest in Brunei, namely the taxonomic treatment of a new species of the leaf litter chrysomelid
We worked in the vicinity of the Kuala Belalong Field Studies Centre (KBFSC) in the Ulu Temburong National Park in the Temburong district of Brunei. We collected specimens at the start of the ‘Ashton Trail’ just west of KBFSC, adjacent to the ‘Earthwatch Plot’ (
On 27.09.2018 and 1.10.2018, we carried out the following field workshop. Field course participants collected leaf litter from two microhabitats, sampled separately (~75 l each): (i) open forest floor and (ii) the area between buttress roots. Leaf litter was then passed through a 1-cm mesh-width beetle sieve and subsequently extracted in a Winkler apparatus, the yield of which was preserved in 96% ethanol. This was then sorted under a dissection microscope and all
Morphological examinations were carried out in the field lab with a Nikon SMZ445 dissection microscope with 10× eye pieces (magnification up to 35×), a Leica ICC50 HD compound microscope and basic dissection materials. Photographs were made either with a smartphone through the eyepiece of a microscope or on a translucent white acrylic sheet with a Nikon D800e fitted with a Laowa 25 mm ultra-macro lens (lighting provided by three flashes, one of which was backlighting the subject). Images were processed in Adobe Lightroom and subsequently stacked in Adobe Photoshop CS6. Genitalia and other dissected parts were embedded in polyvinylpyrrolidone (
One individual (TxExBr0004w-1) was analysed genetically as follows. DNA was isolated from a sample of abdominal soft tissue using the DNeasy Blood & Tissue Kit (Qiagen) and the extracted DNA was then purified with AMPureXP beads (Beckman Coulter). Around 10 ng of DNA were used in a PCR to generate amplicons for the COI barcoding region, using general primers (LCO1490 and HC02198;
Body orange-red, small, nearly hemispherical, 1.15-1.30 mm long and 0.9-1.1 mm wide (i.e. ca. 1.25 times as long as wide) (Fig.
The most important diagnostic features in which
The species is named after the Belalong river; the new species was recorded in the close vicinity of the river’s left bank. Following Article 51C of the Code (
Known only from a location near the confluence of the Belalong and Temburong rivers, at 120 m elevation (Kuala Belalong Field Studies Centre; Fig.
All six specimens we obtained were females. The spermatheca in
These and previous results (
Despite the present single-species description based on limited material from a single locality, we believe that taxonomic work is best carried out in the context of larger revisions. However, we think that concise treatments of single species such as we present here, have value (
We thank the following Taxon Expeditions participants and instructors for assistance in the field and discussions: Simon Berenyi, Brock Thomas Boslem, Massimo Delledonne, Hendrik Freitag, Werner de Gier, and Clister Pangantihon. We gratefully acknowledge Mr. Rodzay Wahab and his staff Mohammad Salleh and Teddy Chua at KBFSC for support and staff at IBER for assistance in organising the field course. This field course was carried out under permit UBD/AVC/-RI/1.21.1[a] from Universiti Brunei Darussalam and the Brunei Forestry Department.
All authors participated in the collecting of the specimens. MS, AJE, and WCH sorted the material. MS, AL, AB, and WCH carried out the morphological examinations. WCH edited the images. MP performed the genetic analyses. PE took the photographs. MS and WCH did the drawings. MDdG wrote the habitat descriptions. MS and AT wrote the manuscript. All authors read and approved the manuscript.
Habitat at the type locality of
dorsal view
ventral view
dorsolateral view
lateral aspect
spermatheca
vaginal palpi