There are now more than 28,000 described orthopterans globally (Cigliano et al., 2018) and this figure is likely to increase in the future. The same is true for Southeast Asia, where we are still at a stage of discovering species new to science, and this is partly an artefact of incomplete sampling (Tan et al., 2017a). In one of the most popular biodiversity hotspots, i.e., Borneo, is the Kuala Belalong Field Studies Centre. It is located in the primary lowland and ridge dipterocarp forests of the Ulu Temburong National Park, Brunei Darussalam. Recent collection of orthopterans in the area led to the discovery of several new species of katydids (Tan et al., 2017b; Tan Wahab, 2017a) and crickets (Tan et al., 2017c; Tan Wahab, 2017b). Here, we describe another new species of katydid, from the genus Tapiena Bolívar, 1906. Tapiena currently consists of 26 species (Tan et al., 2015) and is distributed around Asia and even Africa. In Borneo, only one species is known: Tapiena incisa Karny, 1923 from Sarawak (see Karny, 1923). The new species Tapiena paraincisa sp. nov. represents the second species described from Borneo.
Three new species were described from Borneo: Itara (Bornitara) spinosa sp. nov. and Aphonoides duri sp. nov. from Brunei and Varitrella (Cantotrella) suikei sp. nov. from Sandakan in Sabah. We describe the call of Varitrella (Cantotrella) suikei sp. nov. In addition to the new species descriptions, we also report new locality records of other recently discovered species: Borneloria spinosa Gorochov, 2018 in Belait (Brunei Darussalam), species of Anemozara Gorochov, 2014 in Brunei Darussalam and Terrozacla borneo Gorochov, 2014 in Belait.
Recent orthopteran surveys in the hyper-diverse Borneo, i.e., Brunei Darussalam and Sandakan in Sabah, allow us to review the scaly crickets from the subfamily Mogoplistinae there. We discover and describe the male, as well as formally naming Cycloptiloides bimaculata Tan, Japir Chung, sp. nov. from Sandakan. This species was previously described as sp. 1 in a comprehensive revision by Ingrisch (2006) but only the females were known. We also describe Ectatoderus nigrofasciatus Tan Wahab, sp. nov. from Brunei Darussalam. New locality records are reported for Apterornebius kinabalu Ingrisch, 2006 in Sandakan (Sabah) and Ornebius pullus Ingrisch, 2006 in Belait District (Brunei).
The taxonomy of poorly known crickets from the genus Pendleburyella Chopard, 1969 (Gryllidae, Pentacentrinae) is reviewed. The type specimens of described species were re-located and re-examined. Based on more recent collections, we describe two new species: Pendleburyella eirmosa sp. nov. and Pendleburyella pimela sp. nov., from Brunei Darussalam and Singapore respectively. The new material also allowed us to examine the male genitalia and describe the male calling song of the genus for the first time.
Three species new to science of the Gryllid subfamilies Gryllinae and Pteroplistinae are described from Brunei: (1) Mimicogryllus splendens Tan, Gorochov Wahab, sp. nov., (2) Pteroplistes bruneiensis Tan, Gorochov Wahab, sp. nov., and (3) Tembelingiola belaitensis Tan, Gorochov Wahab, sp. nov. A new species of cricket of the subfamily Phaloriinae is also described from Sandakan, eastern Sabah: Vescelia sepilokensis Tan, Gorochov, Japir Chung, sp. nov.
A species of scaly cricket is described here: Ornebius lupus sp. nov. from the mangrove forests in Singapore. Ornebius pullus Ingrisch, 2006 is recorded in eastern Sabah for the first time. The calling songs of Cycloptiloides bimaculatus Tan et al., 2021 and Ornebius pullus from Sabah are described. We also revise the diagnosis of Ectatoderus nigrofasciatus Tan et al., 2021 from Brunei Darussalam.