ODONATOLOGICA Journal of the Societas Internationalis Odonatologica

Contents Volume 31, Issue 2 2002

Cordero Rivera, A.; Egido Perez, F. J.; Andres, J. A. The effect of handling damage, mobility, body size, and fluctuating asymmetry on lifetime mating success of Ischnura graellsii (Rambur) (Zygoptera: Coenagrionidae) p.  117-128. Several spp. of odonates have been the subject of sexual selection studies. In non-territorial species most variance in lifetime mating success (LMS) is accounted for by lifespan and specially by the number of visits, and random factors (like rainy weather) can have strong effect on reproductive success. Here we present the study of 2 natural populations of I. graellsii by marking-recapture methods. Our results show that male mating success is related to body size, mobility and handling damage, but not to fluctuating asymmetry. Larger males had greater success in both populations, a result in agreement with previous findings on the same sp. Nevertheless, multivariate analyses indicate that body length was a significant correlate of LMS in just one of the studied populations. We estimated a mobility index for males averaging the distance between consecutive resightings. For long-lived males, we found a positive relationship between mobility and LMS. There was a clear effect of leg loss during marking on survivorship, and a marginally significant negative effect on LMS. Finally, we studied the effect of wing fluctuating asymmetry (FA) on LMS by capturing a sample of marked individuals at the end of field work. Results suggest that FA is not an important correlate of LMS in this sp.

De Marco, P.; Resende, D. C. Activity patterns and thermoregulation in a tropical dragonfly assemblage p.  129-138. Solar exposure is a key factor determining odonate activity, particularly in tropical areas. Small sized perchers, classified as thermal conformers, can begin their activity when air temperature is sufficiently high, and larger species become active when direct exposure to the sun is possible. In this study, the activity patterns in a neotropical dragonfly assemblage present on the Federal University of Vicosa, SE Brazil, have been described and following predictions about their thermoregulatory behaviour tested: (a) a decrease in activity of the percher dragonflies in the warmest periods is expected due to high thoracic temperatures; (b) conformers species will be controlled by temperature, not luminosity, whereas in heliothermic species, the initiation and termination of their activity is only constrained by luminosity. In the dry season, low air temperatures represent a limiting factor to the beginning and the end of activity, resulting in a shorter total activity time. Orthemis discolor and Micrathyria hesperis showed a decrease in activity in the middle of the day in the rainy season. Perithemis mooma was the only sp. that had a higher abundance near midday. As this sp. had a light-coloured thorax compared to the others, it is suggested that it could minimize the effect of the high temperatures. There is a clear effect of season on activity time, and also large differences in the intensity of this effect among species. When clouds precluded direct exposure to sun, variations only in the temperature did not affect the activity of Erythrodiplax fusca, M. hesperis and O. discolor, but the activity of the small sized P. mooma remained dependent on temperature. These results highlighted that the minimum body size to be a heliotherm could be a complex function of behavioural and morphological characteristics, including body colour, preferred substrate and perch posture.

De Marmels, J. A study of Chromagrion Needham, 1903, Hesperagrion Calvert, 1902, and Zoniagrion Kennedy, 1917: Three monotypic North American damselfly genera with uncertain generic relationships (Zygoptera: Coenagrionidae) p. 139-150. Comparative morphology identifies Chromagrion as the sister genus of Pyrrhosoma Charp. The genera Hesperagrion, Anisagrion Selys, Apanisagrion Kennedy and Calvertagrion St. Quentin probably form a monophyletic group as they share a bifid apical penis segment armed with a pair of sclerotized spine-like processes. A new interpretation of certain penis structures, and biogeographic considerations, suggest that Zoniagrion is probably a primitive genus, which occupies a basal position on the stem of the Acanthagrion-series, within the ischnurine Coenagrionidae.

Samways, M. J. Red-listed Odonata of Africa p. 151-170. The Red-Listed African Odon. spp. are re-assessed and are assigned or re-assigned to the IUCN Categories of Threat. It is important to distinguish between those species that are simply rare, those that are 'Data Deficient' and those that are genuinely threatened. It is also important to consider the 'Extinct' category very carefully as premature inclusion of a taxon in this category can preclude further searches for it. The IUCN Categories of Threat were found to be very workable for the African Odon. Problems are more to do with the practicalities of doing the field assessments, rather than with the categorisation itself. While the Red List is of enormous value when considering one species at a time, it should not be seen as a generalized data base amenable to comparative assemblage statistics, which are likely to reveal more on assessment efforts than on the organisms.

Andrew, R. J. Egg chorionic ultrastructure of the dragonfly Tramea virginia (Rambur) (Anisoptera: Libellulidae) p. 171-175. SEM studies reveal that the egg chorion of T. virginia is divided into an outer soft exochorion and an inner tough endochorion. The exochorion expands into a jelly-like, sticky coat in water, while the endochorion is smooth, thin and unsculptured. The apically situated micropylar apparatus is formed of a large, dome-shaped, sperm-storage chamber and a small, flat, micropylar stalk which contains a pair of circular micropylar orifices. The micropylar apparatus is encircled by an exochorionic collar. The chorion is modified in accordance with the aquatic (still-water) mode of oviposition exhibited by this species while the micropylar apparatus is shaped to fit in the fertilization pore of the vagina.

Daigle, J. J. Telebasis bickorum spec. nov. from Bolivia (Zygoptera: Coenagrionidae) p. 177-180. The new sp. is described from Bolivia (holotype male: Santa Cruz Dept., Ichilo Province, Buena Vista, February 2001; allotype female: same data as holotype). Holotype deposited in Universidad Autonoma "Gabriel Rene Moreno" (U.A.G.R.M.) in Santa Cruz, Bolivia; allotype deposited in the Florida State Collection of Arthropods in Gainesville, Florida, USA. Both sexes differ by the long and narrow black mesopleural suture on the thorax and acuminate male cerci which are longer than the paraprocts.

Gonzalez-Soriano, E. Leptobasis melinogaster spec. nov., a new species from Mexico (Zygoptera: Coenagrionidae) p. 181-185. The new sp. is described, illustrated and compared with Leptobasis vacillans Hag. in Sel. and L. candelaria Alayo. A key to separate malemale of Mexican and Central American spp. of Leptobasis is provided.

Hartung, M. Heteragrion palmichale spec. nov., a new damselfly from the Cordillera de la Costa, Venezuela (Zygoptera: Megapodagrionidae) p. 187-191. The new sp. is described from the Cordillera de la Costa in Venezuela. Holotype male: Venezuela, Edo. Carabobo, Bejuma, Cerro de Paja mountain, alt. ca 1200 m, 13-VI-1992; paratype male, same data; the holotype is to be deposited in MIZA, Maracay, Venezuela. No other specimens are known to date. This is one of the largest spp. within Heteragrion. The appendices are strongly arched in contrast to other members of the genus. Some similarities of appendices or size exist with H. tricellulare Calv., simulatum Wllmsn, peregrinum Wllmsn, and icterops Sel. The new sp. was found in an inhabited region of the Cordillera de la Costa, near Bejuma, Carabobo.

Legrand, J. [Tragogomphus ellioti spec. nov., a new dragonfly from Aequatorial Africa (Anisoptera: Gomphidae).] p. 193-197. The new sp. is described and illustrated from a single male, collected in Gabon. Holotype male: Eastern Gabon, Makokou area, 1-XI-1976; deposited in MNHN, Paris. It lives in the upper sections of forest streams. The new sp. seems to be close to T. aurivillii Sjostedt, 1899, but it is very different from the sympatric T. tenaculatus (Fraser, 1926), known from this region.

Machado, A. B. M. Neoneura lucas spec. nov. from Brazilian Pantanal (Zygoptera: Protoneuridae) p. 199-204. The new sp. is described and illustrated from 15 male and 2 female, collected in the Pantanal Region of Brazil. Holotype male, allotype female: Pocone, Rio Cuiaba, Mato Grosso, Feb. 1986; deposited in the author's collection, Belo Horizonte. In view of the arrangement of the decumbent process of the dorsal branch of the superior appendage, the new sp. belongs to the fulvicollis-group R.W. GARRISON (1999, Odonatologica 28:343-375), differing from the other spp. of this group mainly by the presence of a small ventral hook on the apex of the upper branch of the superior appendage.

Tennessen, K. J. Telebasis simulata spec. nov. from South America, previously confused with T. sanguinalis Calvert (Zygoptera: Coenagrionidae) p.  205-210. The new sp. (holotype male, allotype female: Brazil, State of Amazonas, Manaus, 20-VI-1922; deposited in FSCA, Gainesville, Fla, USA) is described and illustrated based on 82 male and 15 female from Brazil, Surinam, Trinidad and Venezuela. It most closely resembles T. sanguinalis but differs mainly by: (1) translucent dorsal flap of terminal penile segment rectangular in lateral view, gradually tapered to posterior lateral angle (vs flap with a posterolateral lobe-like extension directed posteriorly); (2) cerci 1.6 to 1.8 times as long as paraprocts (vs 2.0 times as long); (3) rear of head half black, black marking extending to occipital foramen (vs pale except for a pair of small, dark circular spots). T. sanguinalis is known only from central Bolivia and western Brazil.

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