Robin W.J. Ngiam

A balancing act in urban social-ecology: human appreciation, ponds and dragonflies

Green spaces in cities provide cultural ecosystems services (CES) such as nature connection, wildlife interaction and aesthetic appreciation which can improve aspects of human well-being. Recognising these benefits, researchers are now examining the complex relationship between humans and nature in urban social-ecology. Most studies investigate people’s appreciation and valuation of different green space features and their contribution to urban biodiversity. Recommendations arising from such studies are best practices to achieve a balance between landscape aesthetic and ecological objectives, but many knowledge gaps still exist. In a social-ecological project in Greater London, appreciation of ponds and dragonflies in urban green spaces, and the environmental factors determining dragonfly diversity were investigated. We found ponds and their appearance were valued by people as enhancing their green space experience. The preference for wild-looking ponds was moderate. Dragonflies were enjoyed for their colour and high visibility, especially by those who had basic dragonfly knowledge. Species richness of dragonflies was positively associated with habitat heterogeneity in and around a pond. However, people were unable to relate a heterogeneous pond to more dragonfly species. For the first time, some factors that influence the human appreciation-ponds-dragonflies (HPD) relationship in an urban context are revealed. To fully realise the CES potential of ponds and dragonflies in Greater London, a HPD framework is proposed. The framework underpins strategies that foster cultural sustainability for ponds and dragonfly conservation.

A description of the larva of Heliaeschna uninervulata Martin (Odonata: Aeshnidae) from Singapore, with notes on its relationships

The larva of Heliaeschna uninervulata is described and figured for the first time. Its characters mostly fall within the limits of variation of Gynacantha spp. Comparison of the larval characters of H. filostyla, the only other member of the genus for which the larva is known, suggests that it is not congeneric with H. uninervulata.

Towards holomorphology in entomology: rapid and cost-effective adult-larva matching using NGS barcodes: Life-history stage matching with NGS barcodes

In many taxa the morphology of females and immatures is poorly known because species descriptions and identification tools have a male bias. The root causes are problems with matching life‐history stages and genders belonging to the same species. Such matching is time‐consuming when conventional methods are used (e.g. rearing) and expensive when the stages are matched with DNA barcodes. Unfortunately, the lack of associations is not a trivial problem because it renders a large part of the phenome of insects unexplored, although larvae and females are useful sources of characters for descriptive and phylogenetic purposes. In addition, many collectors intentionally avoid females and immature stages, which skews survey results, interferes with collecting life‐history information, and makes it less likely that rare species are discovered. These problems even exist for well‐studied taxa like Odonata, where obtaining adult–larva matches relies largely on rearing. Here we demonstrate how the matching problem can be addressed with cost‐effective tagged amplicon sequencing of a 313‐bp segment of cox1 with next‐generation sequencing (NGS) (‘NGS barcoding’). We illustrate the value of this approach based on Singapores odonate fauna which is of a similar size as the European fauna (Singapore, 122 extant species; Europe, 138 recorded species). We match the larvae and adults of 59 species by first creating a barcode database for 338 identified adult specimens representing 83 species. We then sequence 1178 larvae from a wide range of sources. We successfully barcode 1123 specimens, which leads to adult–larva matches for 59 species based on our own barcodes (55) and online barcode databases (4). With these additions, 84 of the 131 species recorded in Singapore have now been associated with a species name. Most common species are now matched (83%), and good progress has been made for vulnerable/near‐threatened (55%), endangered (53%), and critically endangered species (38%). We used nondestructive DNA extraction methods in order to be able to use high‐resolution imaging of matched larvae to establish a publicly available digital reference collection for odonates which is incorporated into ‘Biodiversity of Singapore’ ( https://singapore.biodiversity.online/). We suggest that the methods described here are suitable for many insect taxa because NGS barcoding allows for fast and low‐cost matching of well‐studied life‐history stages with neglected semaphoronts (eggs, larvae, females). We estimate that the specimen‐specific amplicons in this study (c. 1500 specimens) can now be obtained within eight working days and that the laboratory and sequencing cost is c. US

The larva of Tetracanthagyna plagiata, with notes on its biology and comparisons with congeneric species (Odonata: Aeshnidae)

600 (< US

A description of the larva of Heliaeschna idae Brauer from Borneo, with a supplementary note on the larva of H. univervulata Martin (Odonata: Aeshnidae)

0.40 per specimen).

Chlorogomphus manau sp. nov. from Sarawak, Malaysia (Odonata: Chlorogomphidae)

Abstract The F stadium larva of both sexes of Tetracanthagyna plagiata is described and figured based on exuviae from which confirmed adult specimens had been reared. Larvae were originally collected in small, slow forest streams in Singapore, and in captivity were fed on local shrimp and small fish species. The known larvae of Tetracanthagyna species, T. degorsi, T. plagiata and T. waterhousei are compared and characters for separating the three species are tabled and figured. T. plagiata larvae reared in captivity exhibited obligate ambush predation and ballistic defaecation.

Revision of the Genus Leptogomphus Selys in Borneo, including gene trees and a two marker molecular phylogeny (Odonata: Anisoptera: Gomphidae)

The final instar larva of Heliaeschna idae Brauer is described and figured for the first time based on the exuvia from an advanced female larva collected in Sarawak, Borneo (East Malaysia). It is compared with the known larvae of the genus and is concluded to be most closely allied to Heliaeschna simplicia Karsch, with which it shares a unique structure on the anterior margin of the prementum of the labium, along with several other distinctive characters. The dorsal structure of the head of H. uninervulata is re-examined and illustrated. It is shown to bear a prominent convexity and tuft of long setae on the vertex which is similar to a structure previously recorded only in H. simplicia, and which is only weakly developed in H. idae. The taxonomic implications of these partly conflicting observations are discussed and it is concluded the Oriental members of the genus Heliaeschna might be separated into two or three separate genera, which are as yet unnamed.

Oligoaeschna sirindhornae sp. nov., a new dragonfly species from Thailand (Odonata: Anisoptera: Aeshnidae)

Chlorogomphus manau sp. nov. (holotype ♂: Borneo, Sarawak, Kapit Division, Hose Mountains, 15 April 2011, RMNH) from Malaysia is described from the male and compared with other regional Chlorogomphus species.

Previously unpublished Odonata records from Sarawak, Borneo,Part III. Sri Aman, Sibu and Kapit Divisions

The Bornean members of the genus Leptogomphus Selys are revised. Two new species are described: Leptogomphus schieli sp. nov. (holotype ♂, Gunung Penrissen, Kuching Division, Sarawak, Malaysia, to be deposited in BMNH) and Leptogomphus sii sp. nov. (holotype ♂, Sungai Sii, upper Baram, Miri Division, Sarawak, Malaysia, in RMNH). Leptogomphus mariae Lieftinck, 1948 is considered to be a junior synonym of L. coomansi Laidlaw, 1936. The true male of L. pasia van Tol, 1990 is described for the first time; male specimens previously treated as L. pasia or L. cf pasia actually belong to a taxon closely allied to, and possibly merely a form of, L. coomansi. A description is given of the female of another new species, but the species is not named in the absence of the male. Female specimens from south-western Sarawak, similar to L. williamsoni Laidlaw, 1912, are considered likely to also represent a distinct species. The female of L. pendleburyi Laidlaw, 1934 is described for the first time and fresh descriptions of the males of L. coomansi, L. pendleburyi and L. williamsoni, and the female of L. coomansi are given. Keys to both sexes, and distribution maps are given. A molecular analysis of the Bornean species (except L. schieli) using the COI and ITS markers is presented.

Figure 1 In Oligoaeschna Sirindhornae Sp. Nov., A New Dragonfly Species From Thailand (Odonata: Anisoptera: Aeshnidae)

Oligoaeschna sirindhornae sp. nov. is described from a male from Sakaerat Silvicultural Research Station, Nakhon Ratchasima Province in Thailand. It is the only known Oligoaeschna species recorded from Thailand since Oligoaeschna pramoti (Yeh, 2000) and Oligoaeschna minuta (Hämäläinen & Pinratana, 1999) were transferred to the genus Sarasaeschna.