It has been shown that life history, behavioural as well as morphological traits vary with the habitats occupied by odonate larvae. Here we ask the following questions: (1) Are the morphological traits, which are associated with perception and foraging, related to the larval habitat? (2) Do these traits influence foraging success and growth rate? We…
Descriptions and illustrations of the final stadium larvae of Gomphidia bredoi, G. gamblesi and G. quarrei are presented, based on exuviae collected in Ivory Coast, Cameroon, Kenya and Namibia. The three species can be separated by the presence/absence and shape of an abdominal dorsal spine on segment 9, by the numbers of abdominal lateral spines…
Heteragrion makiritare sp. nov. is described from two males from the Pantepui region – holotype: Venezuela, Amazonas State, Marahuaka, Sima (3°43′N, 65°31′W), 1,140 m a.s.l., MIZA, no. 17250. It belongs in the species group whose paraprocts are absent in the male sex. The identity of H. macilentum is elucidated by examining its lectotype and a…
The article considers the phenomenon of ballistic defaecation by odonate larvae, exhibited by certain Anisoptera but not by any Zygoptera, and explores two possibilities: (1) that ballistic defaecation in Anisoptera may correlate with increased foraging success (the ‘Wudkevich Hypothesis’) by distancing the prey’s alarm pheromone, persisting in the pellet after defaecation, from the larva’s ambush…
Boyeria vinosa is a common anisopteran in the southeastern United States. Here we describe relationships between the abundance of B. vinosa larvae and the chemical, physical and biological properties of the Enoree River of South Carolina and nine of its tributary stream systems. Chemical profiles were conducted weekly for seven weeks at 63 sites in…
This study records 175 species of odonates from Brunei, representing more than half the known Bornean fauna. Of these, 169 species were collected by the author and associates using a systematic sampling protocol at 35 sites throughout the country. Sites were located in diverse habitats: in primary forest, natural lakes and marshes and degraded areas.
Aeshna (Hesperaeschna) condor sp. nov. is described and illustrated from four males and six exuviae. The adult color pattern does not resemble that of any other Venezuelan species, but structurally the new species comes closest to A. (H.) punctata and A. (H.) joannisi. This latter is here recorded for the first time from Venezuela, and…
A detailed description of the final stadium of Somatochlora hineana, with brief notes on the penultimate stadium, is presented. An illustration of the entire larva and separate line drawings of the labium and dorsal and lateral views of the abdomen are also included. The habitat of the larva is discussed briefly. Combinations of diagnostic characters…
A small inconspicuous spine, first detected at the base of the distal-most seta on each labial palpus of early stadia of two species of Enallagma, is reported to occur in final-stadium (F-0) larvae of Palaearctic and Nearctic E. cyathigerum, in F-0 of 31 other Nearctic species of Enallagma and in F-0 of three other coenagrionid…
In the dragonfly Anax nigrofasciatus nigrofasciatus (Aeshnidae, Anisoptera), the X-tissue is the tissue which occupies the posterior corner of the larval eye and which forms the large facet region in the dorsal part of the adult compound eye after emergence. In the early period of the last larval instar, an ommatidial retinula of the X-tissue…