Description of new species of Hymenoptera from Borneo
P. Cameron published this taxonomic monograph in 1907 in the Journal of the Straits Branch of the Royal Asiatic Society (Vol. 48), describing a suite of new Hymenoptera species collected primarily at Kuching, Borneo, by John Hewitt, Curator of the Sarawak Museum. The work establishes Iphiaulax as the most speciose genus of Hymenoptera in Malaya and introduces two new genera (Hytophatnus, Aulojoppa, and Xoridesopus) alongside numerous new species across the Braconidae, Ichneumonidae, and Vespidae.
Summary
The paper is organised into four sections, each addressing a different taxonomic group. The largest section (A) treats ten species of Iphiaulax (Braconidae), which Cameron groups by the morphology of the plate on the base of the second abdominal segment—a character he uses to divide them into four informal groups. He re-describes I. insignis Smith (1857) from Borneo and distinguishes it from Szepligeti’s Javan insignis, which he considers a different species based on ovipositor length and body proportions. The remaining nine species are new to science, each described with detailed attention to abdominal striation patterns, keel morphology, and colouration. Cameron also describes Chaolta laticauda, a new species in a related braconid genus.
Section B introduces three new genera of Ichneumonidae. Hytophatnus is characterised by a flat, unseparated clypeus, confluent basal areæ of the metanotum, and a tuberculate post-scutellum; its type species H. lineatus is a 9 mm female from Kuching. Aulojoppa (tribe Joppini) is distinguished by a large cubital head, rounded clypeal apex, and a long projecting ovipositor; its type A. spilocephala is a 10 mm female. Cameron also describes Mesostenoides angulicollis (a Mesostenus with a spined metanotum), the new genus Xoridesopus with its type X. annulicornis (placed provisionally in the Acoenitini), and Hadrocryptus dentatus, the latter distinguished from Himalayan congeners by teeth on the underside of the abdominal petiole.
Sections C and D are briefer. Cameron describes two new species of Mellinus (a sphecid wasp), M. nigrolineatus and M. nigromaculatus, and provides a three-species key for Bornean Mellinus. In the Vespidae, he describes Icaria parvimaculata from Marup and records I. intermedia from Transan, I. maculifrons from Merdang, and notes intraspecific variation in I. artifex Saussure from Kuching and Sadong.
Key Findings
- Cameron identifies Iphiaulax as the most abundant genus of Hymenoptera in Malaya by species number, describing ten species (one re-description, nine new) from Kuching alone (p. 1).
- Iphiaulax insignis Smith (1857) is re-described from a 22 mm female with an 83 mm ovipositor; Cameron separates it from Szepligeti’s Javan insignis (55 mm ovipositor, 20 mm body) on the basis of ovipositor length and abdominal proportions (p. 2).
- Three new genera are erected: Hytophatnus (Ichneumonidae, type H. lineatus, 9 mm), Aulojoppa (Joppini, type A. spilocephala, 10 mm), and Xoridesopus (Acoenitini, type X. annulicornis, 12 mm) (pp. 12–19).
- Hadrocryptus dentatus (15 mm) is distinguished from the Eastern Himalayan H. nasutus and H. tuberculatus by four short teeth on the lower side of the abdominal petiole (pp. 21–22).
- A three-species key is provided for Bornean Mellinus, separating M. crabriformis Smith (black thorax, golden pubescence) from the two new testaceous species M. nigrolineatus (10 mm) and M. nigromaculatus (8 mm) (pp. 22–25).
- Icaria parvimaculata (6 mm to end of second abdominal segment) is described from Marup, May, and noted to approach I. lugubris Smith in colouration but to resemble I. malayana in form (p. 25).
Conclusion
Cameron’s paper serves as a foundational contribution to the hymenopteran fauna of Borneo, establishing the extraordinary diversity of Iphiaulax in the region and providing the first descriptions of several genera that would remain important in subsequent ichneumonid systematics. His morphological groupings of Iphiaulax by second-segment plate morphology represent an early attempt at intrageneric classification that anticipates later revisions of the genus.
Context
- P. Cameron (1857–1945) was a British entomologist attached to the British Museum (Natural History) who published extensively on Oriental Hymenoptera; this paper draws on specimens in the Sarawak Museum collected by John Hewitt, its curator.
- The work is a standard taxonomic description of the period, relying entirely on the type specimens in the Sarawak Museum collection; it has no archival or historiographical dimension beyond its contribution to the faunal inventory of Borneo.