A new species Leptogomphus tioman is described based on male specimens collected from Tioman Island, Peninsular Malaysia. It is close to Leptogomphus risi Laidlaw in thoracic markings but is readily distinguished by its anal appendages and accessory genitalia.
Megalogomphus sumatranus (Krüger, 1899) and its allies in Sundaland are reviewed. The accessory genitalia of the males of this genus, hardly considered previously, are found to be taxonomically informative. The taxon from Borneo previously treated as M. sumatranus is described from both sexes as M. buddi sp. nov. (holotype ♂ Sungai Datai, Nanga Bloh, Lanjak Entimau Wildlife Sanctuary, Kapit Division, Sarawak, Malaysia, 22 viii 2013, leg. J. anak Awan M. anak Adau; deposited at the Naturalis Biodiversity Center, Leiden, the Netherlands). Megalogomphus borneensis (Laidlaw, 1914), described as a subspecies of M. icterops (Martin, 1903) and subsequently relegated to the synonymy of that species, is considered to be a distinct species. Megalogomphus icterops is however considered to be a junior synonym of M. sumatranus. A re-description of the holotype of Megalogomphus borneensis is provided as is the first description of the female. Descriptive notes with illustrations of Megalogomphus sumatranus are given.
Coeliccia junis sp. nov. (holotype male from Borneo, Sarawak, Bintulu Division, Planted Forest Project, Bukit Mina Wildlife Corridor, "Day 4" stream near Bukit Nyegoh and Bukit Jugam, near small brown water pool, 10 viii 2018, deposited in the Naturalis Biodiversity Center, Leiden, the Netherlands) and Coeliccia roberti sp. nov. (holotype male from Borneo, Sarawak, Miri Division, Lambir Hills National Park, small stream on Oil Well Trail, 22 iv 2011, deposited in the Naturalis Biodiversity Center, Leiden, the Netherlands) are described from Borneo. Both new species belong to the Coeliccia membranipes-group and bring the number of named species known from the group from Borneo to nine and the total number of named species from Borneo currently placed in Coeliccia to 15. Coeliccia junis is only known from a small area in Sarawak, C. roberti is also known from Brunei. Both species are considered likely to be closely allied with C. macrostigma Laidlaw.
The male of Indolestes anomalus Fraser, 1946 is described and the holotype female is depicted. Its occurrence in Vietnam, Thailand and Malaysia is discussed, and the type locality is clarified (South Vietnam, Đồng Nai River basin).
A modified and expanded definition of the Drepanosticta carmichaeli-group is given. This includes the species: D. annandalei Fraser, 1924, D. brownelli Tinkham, 1938, D. carmichaeli (Laidlaw, 1915), D. emtrai Dow, Kompier Phan, 2018, D. hongkongensis Wilson, 1997, D. jurzitzai Hmlinen, 1999, D. sumatrana Sasamoto Karube, 2007, D. tenella Lieftinck, 1935, D. vietnamica Asahina, 1997 and D. wildermuthi sp. nov.). The species of the group are reviewed and in most cases illustrated, diagnostic notes are given wherever possible. Drepanosticta polychromatica Fraser, 1931 is considered to be a junior synonym of D. carmichaeli and variation in D. carmichaeli is discussed. Drepanosticta wildermuthi sp. nov. from the Central Highlands of Vietnam (holotype male from Bao Loc district, Lam Dong Province) is described. The female of D. jurzitzai Hmlinen, 1999 is described for the first time. A key to the males of the Drepanosticta carmichaeli-group is provided.
Swarm intelligence is a discipline which makes use of a number of agents for solving optimization problems by producing low cost, fast and robust solutions. The dragonfly algorithm (DA), a recently proposed swarm intelligence algorithm, is inspired by the dynamic and static swarming behaviors of dragonflies, and it has been found to have a higher performance in comparison to other swarm intelligence and evolutionary algorithms in numerous applications. There are only a few surveys about the dragonfly algorithm, and we have found that they are limited in certain aspects. Hence, in this paper, we present a more comprehensive survey about DA, its applications in various domains, and its performance as compared to other swarm intelligence algorithms. We also analyze the hybrids of DA, the methods they employ to enhance the original DA, their performance as compared to the original DA, and their limitations. Moreover, we categorize the hybrids of DA according to the type of problem that they have been applied to, their objectives, and the methods that they utilize.
Coeliccia matok sp. nov. (holotype male from Borneo, Sarawak, Samarahan Division, peat swamp forest at old UNIMAS campus, 25 ii 2008, to be deposited in BMNH) and Coeliccia paludensis sp. nov. (holotype male from Borneo, Kalimantan Tengah, peat swamp forest in ex Mega Rice Project Block E, 18 vi 2012, in RMNH) are described from Borneo. The two new species are apparently confined to peat swamp forest (C. paludensis) or largely confined to peat swamp forest and related forest formations (C. matok). Coeliccia macrostigma Laidlaw is redescribed and all available information on it is summarised. Additional terminology for characters of the prothorax in Coeliccia species is introduced. Distribution maps are given for all three species considered.
Prodasineura yulan is described from a male from Maludam National Park, Betong Division, Sarawak, Malaysian Borneo. It is allied to Prodasineura interrupta.
Matched MeSH terms: Odonata/anatomy & histology; Odonata/classification*; Odonata/growth & development
The final instar larva of Acrogomphus jubilaris Lieftinck, 1964, is described and figured for the first time based on exuviae from four male and one female larvae collected in Sarawak, Malaysian Borneo. The adults of A. jubilaris are very rarely encountered. The larvae, however, are surprisingly common in forest streams in Borneo. It is compared with A. malayanus Laidlaw, 1925 and A. walshae Lieftinck, 1935, and notes on behavior, distribution and habitat are included. A map including all known records of A. jubilaris is provided.
Matched MeSH terms: Odonata/anatomy & histology; Odonata/classification*; Odonata/growth & development
Onychogomphus marijanmatoki is described from a male from Gunung Mulu National Park, Miri Division, Sarawak, Malaysian Borneo. One of only two onychogomphine species known from Borneo, it differs from all others of the group in characters of the genital ligula and terminal appendages.
T. iban sp. nov. is described from the Lanjak Entimau Wildlife Sanctuary in Sarawak, Malaysian Borneo. Both sexes can be distinguished from all other species of Telosticta by the form of the antehumeral markings.
Drepanosticta emtrai sp. nov. is described from Vietnam (holotype male Ha Tinh Province, 9 vi 2015, to be deposited in RMNH). The new species is allied to D. carmichaeli (Laidlaw, 1915) and a number of other species of Drepanosticta including D. vietnamica Asahina, 1997. New illustrations of the paratype of D. vietnamica are provided and the species is discussed. The Drepanosticta carmichaeli-group, to which the above mentioned species belong, is defined and discussed.
Podolestes parvus sp. nov. is described and illustrated from both sexes from Sarawak, Malaysian Borneo (holotype male Maludam National Park, Betong Division, Sarawak, 10 vii 2012, deposited in RMNH). The new species is closest to P. atomarius Lieftinck, 1950 and is the smallest species yet known in its genus. A full set illustrations of P. atomarius is provided for comparison. [Species Zoobank URL: urn:lsid:zoobank.org:act:EE7ABAB0-8683-4D25-8A2C-76977931FD87].
Drepanosticta rahmani sp. nov. (holotype ♂, steep tributary to stream in hills between Baling and Gulai, north west Kedah, Malaysia, 15 xi 2016, leg. R.A. Dow, to be deposited in the Natural History Museum, London) is described from both sexes.
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.
Phaenandrogomphus safei is described from a male from the Kalabakan Forest Reserve, Sabah, Malaysian Borneo. It is the first species of Phaenandrogomphus to be recorded from Borneo. Onychogomphus treadawayi, known from Busuanga Island in the Palawan region of the Philippines, is transferred to Phaenandrogomphus.
Matched MeSH terms: Odonata/anatomy & histology; Odonata/classification*; Odonata/growth & development
A preliminary study on selected insect communities of Tasik Chini was conducted from 27th May to 2nd June 2004 along three trails namely trail to Sg. Gumum, trail to Kampung Melai and trail to old tin mining area. A total of eight Malaise traps were installed along the trail to Sg. Gumum while sweeping net and 10 yellow pan traps per trail were used to sample insects along the other two trails. A total of 502 insect individuals consisting of eight orders and 46 families were successfully collected. Of these, the hymenopterans (ants and wasps) had the most number (298 individuals and 11 families) while the Blattaria was the least number (six individuals and two families). Of the hymenopterans, the ichneumonids had the most individuals collected (52) followed by evaniid (50) and vespid wasps (41). For the Coleopterans, Cleridae were the most collected (26) during this short study followed by Anthribidae (13). There were 62 of individuals Odonata consisting of 9 species identified.
Telosticta fugispinosa sp. nov. (holotype male, from Borneo, Sabah, West Coast division, Crocker Range National Park, Inobong, Kimamabang waterfall stream system, 21 ix 2012, deposited in RMNH) is described from Kinabalu National Park and Crocker Range National Park in Sabah, Malaysian Borneo. It is distinguished from all other species of Telosticta by the form of the male anal appendages.
Matched MeSH terms: Odonata/anatomy & histology; Odonata/classification*; Odonata/growth & development
The final instar larva of Orthetrum borneense Kimmins, 1936, is described and figured for the first time based on exuviae from three male and six female larvae collected in Sarawak, Borneo (East Malaysia). It is compared with an early instar larva, which was matched to the adult O. borneense by DNA barcoding, and the known larvae of other species of this genus that occur in the region.
The final stadium larva of Onychargia atrocyana Selys, 1865, is described and illustrated based on two female specimens collected at Gunung Mulu National Park, Sarawak, East Malaysia. The larvae were identified by matching the mitochondrial marker COI with that of known adult specimens from Gunung Mulu, Bintulu and Kuching in Sarawak and from Pahang state in West Malaysia. The specimens presented close matches with all adults in this gene. As O. atrocyana is a taxonomically isolated species with no close congeners in Borneo the determination is beyond doubt. O. atrocyana is the only member of the Onychargiinae for which the larva is known. It is compared with the known larvae of other platycnemidid subfamilies, and the possible significance of larval morphology in higher classification of the group is discussed.