Abstracts 29:1-4

Contents Volume 29 (2000) – Issue 1-4

Costa, J. M.; De Souza, L. O. Irinue; Santos, T. C.
Two new species of Oxyagrion Selys, 1876, with a description of five new larvae (Zygoptera: Coenagrionidae)
pp. 1-15.

O. pseudocardinale sp.n. (holotype male: Brazil, Minas Gerais, Fazenda da Cachoeira F.F. de Souza, 13-II-1990) and O. sulmatogrossense sp. n. (holotype male: Brazil, Mato Grosso do Sul, Campo Grande, Campus UFMS, 24-XII-1997) are described and illustrated. The larvae of O. basale Selys, 1876: O. haematinum Selys, 1876; O. pavidum Selys, 1876; O. santosi Martins, 1967 and O. sulinum Costa, 1978 are described and illustrated for the first time. Keys are provided for the known Oxyagrion spp. and for the known larvae.

Von Ellenrieder, N.
Species composition and temporal variation of odonate assemblages in the subtropical-pampasic ecotone, Buenos Aires, Argentina
pp. 17-30.

Odonata assemblages present in the ecotone between subtropical forest and pampasic grassland in Punta Lara were characterized and compared. Four pools, one in the forest, 2 in grassland (one within a protected area) and one at the limit of both environments, were sampled during July 1996-June 1998. For each sampling station species richness and diversity were calculated, and were compared through 2 similarity coefficients (Jaccard and Winer). The highest species richness and diversity were registered in the forest, and the lowest in the protected grassland. Cluster analysis showed different schemes according to the similarity coefficient considered; a greater similarity between the forest and intermediate pools (Jaccard coefficient), or a greater similarity between grassland areas (Winer coefficient). Some biogeographical implications are discussed.

Wasscher, M. T.; Bos, F. G.
The European dragonflies: Notes on the checklist and on species diversity
pp. 31-43.

Casing natural geographical boundaries, 130 spp. can be considered as European, though when broader political borders are followed this number rises to 136. In addition 20 exotic spp. have been recorded as a result of accidental importation. The highest diversity, defined by the number of spp. per standard area of 250X250 km2, is found in the Alps, while the lowest diversity occurs in the northern parts of mainland Europe and on some islands. Surprisingly, the Mediterranean region is not as rich in spp. as the central part of Europe. When compared with other continents, it is clear that Europe has the lowest number of spp. However, when compared specifically with areas at the same latitude, the Odon. diversity in Europe is relatively average: somewhat higher than expected in the northern regions, somewhat lower than expected in southern regions.

Wilson, K. D. P.
Distributional notes on the genus Rhipidolestes, with descriptions of two new species from South China (Zygoptera: Megapodagrionidae)
pp. 45-50.

 R. alleni sp. n. (holotype male: Da Ming Shan, Guangxi) and R. cyanoflavus sp. n. (holotype male: Bai Yong, Guangdong) are described from South China. A table and map is provided detailing the distribution of all known Rhipidolestes species and subspecies.

Abro, A.
Sperm clusters in Zygoptera (Coenagrionidae, Lestidae, Calopterygidae)
pp. 51-56.

When within the testicular cyst, individual, immature sperm of Lestes sponsa acquire a cap of periacrosomal material. During passage through the spermiducts and vas deferens, the caps of individual sperm coalesce, producing clusters of sperm under a common cap. In Calopteryx virgo, entire sperm cells become embedded in an extracellular homogeneous substance. The joining substance in both species appear to be derived from decomposed surplus cytoplasm sloughed off from developing spermatids. The epithelial lining of the spermiducts adds secretions to this. Clustering of sperm cells was not demonstrated in species of the Coenagrionidae.

Bedjanic, M.
Description of the last larval instar of Epophthalmia vittata cyanocephala Hagen, 1867 (Anisoptera: Corduliidae)
pp. 57-61.

The ultimate instar larva is described and figured from exuviae, collected near Anuradhapura, Sri Lanka. Our present knowledge of the larval forms of the genus is briefly discussed.

Karube, H.
Microgomphus jurzitzai spec. nov., a new dragonfly from southern Vietnam (Anisoptera: Gomphidae)
pp. 63-65.

The new sp. is described and illustrated from 2 male. Holotype male: Lamdong prov., Bao Lok to Ho-Chi-minh Rd, 15-VI-1996; deposited in Author’s institution. It is similar to M. loogali Fraser, from northern Burma, from which it is easily distinguished by the longer inner superior appendages, and by strongly bent, bifid inferior appendages. This is the first member of the genus recorded from Vietnam.

Tennessen, K. J.
Micrathyria sympriona spec. nov., a new dragonfly from Ecuador and Peru (Anisoptera: Libellulidae)
pp. 67-73.

The new sp. (holotype male, allotype female: Ecuador, Zamora Chinchipe prov., grassy marsh 5.5 km SE of Zamora, ca 3000 ft, 4degree10’S, 78degree56’W, 5-XI-1997; deposited at FSCA, Gainesville, FL, USA) is described and compared with M. hypodidyma Calvert. M. sympriona differs in the low, laterally rounded transverse ridge on the venter of abdominal segment 1 which bears 0 to 3 widely spaced black denticles on each side of the median depression, the tips of the outer arms of the hamules surpassing the anterior laminae, and segment 9 all black. Females have abdominal segment 9 sternite convex instead of flat as in M. hypodidyma.

Costa, J. M.; Santos, T. C.
Two new species of Santosia Costa and Santos, 1992 with a description of five new corduliid larvae (Anisoptera: Corduliidae)
pp. 95-111.

S. machadoi sp.n. (holotype male: Parque Nacional da. Serra da Bocaina, Sao Paulo, Brazil; 25-II-1977) and S. newtoni sp.n. (holotype male: Brejo da Lapa, Itatiaia, Rio de Janeiro, Brazil; 19-II-1974) are described and illustrated along with their exuviae. The exuviae of Aeschnosoma marizae Santos, Neocordulia androgynis (Sel.) and N. setifera (Hag.) are also described and illustrated for the first time. The known Santosia spp. and the neotropical corduliid larvae are keyed.

De Marmels, J.
The larva of Allopetalia pustulosa Selys, 1873 (Anisoptera: Aeshnidae), with notes on aeshnoid evolution and biogeography
pp. 113-128.

The larva is described and illustrated from four ultimate instar exuviae (2  reared) and from a younger larva, all from Venezuela. Main characters are a pointed epiproct and spinous mesial carinae of paraprocts. There is some general similarity with larvae of Boyeria McL., but the latter have angled occipital lobes, longer labium and, in some species, a bifid epiproct. Penis is strikingly similar in Allopetalia and Boyeria, the “cornua” coming closer to those found inGomphaeschna Sel. than to the “flagella” as found in the brachytrine Spinaeschna Theisch. and in the austropetaliine Rheopetalia Carle. The “pryeri-group” ofOligoaeschna Sel. is adscribed to Gomphaeschnata LOHMANN (1996, Ent. Z., Essen 106: 209-252), while the “poeciloptera-group” is considered a representative of the archaic Gynacanthini (Aeshnata). Biogeographical problems of Anisoptera, especially those of Gomphaeschnini and Gynacanthini, and of Euphaeida (Zygoptera) are discussed, considering the Pangaea-model and panbiogeographic criteria. Maps and a glossary of some panbiogeographic terms are added.

Westman, A.; Johansson, F.; Nilsson, A. N.
The phylogeny of the genus Leucorrhinia and the evolution of larval spines (Anisoptera: Libellulidae)
pp. 129-136.

A cladistic analysis of the genus Leucorrhinia, based on adult morphological characters, found one most parsimonous tree with a consistency index of 0.35. The evolution of large dorsal larval spines was mapped on the resulting tree. This mapping suggests that the presence of spines is the primitive state withinLeucorrhinia and that they have disappeared on five different occasions, or have disappeared twice on lower branches and reappeared three times higher up in the tree.

Yeh, W. C.; Chen, Y. M.
Descriptions of two new species of the genus Oligoaeschna from northern Taiwan, with notes on the status of the pryeri-group (Anisoptera: Aeshnidae)
pp. 137-150.

2 syntopic new sp. of the pryeri-group Oligoaeschna, O. lieni sp. n. (holotype male: Tsaopi bog, 850m, Yuanshan, Ilan county, northern Taiwan, 11-V-1997) andO. tsaopiensis sp. n. (holotype male: Tsaopi bog, 850m, Yuanshan, Ilan county, northern Taiwan, 11-V-1997) collected from northern Taiwan are named, described and diagnosed. Relationship amongst the members of eastern Asian pryeri-group is discussed and inferred mainly from their male penile structure. With regard to male penile glans structure, the pryeri- group is considered to be the extant sister-group of the nearctic genus Gomphaeschna.

Assis, J. C. F. ; Carvalho, A. L.; Dorville, L. F. M.
Aspects of larval development of Limnetron debile (Karsch), in a mountain stream of Rio de Janeiro State, Brazil (Anisoptera: Aeshnidae)
pp. 151-155.

Quantitative and qualitative samplings performed in a first order mountain stream in the State of Rio de Janeiro, southeastern Brazil, provided 121 larval specimens in the 6 last instars. The total number of larval instars estimated, using Dyar’s rule, is 13, based on head width measurements. There was no significant difference between the number of males and females.

Switzer, P. V.; Schultz, J. K.
The male-male tandem: A novel form of mate guarding in Perithemis tenera (Say) (Anisoptera: Libellulidae)
pp. 157-161.

Observations on male-male tandems are reported; these tandems occur at very low frequency during mate guarding sequences. When initiating a tandem, a male territory resident grabs an intruding male behind the head and flies with him. This behavior is similar to the tandem formation more usually associated with male-female pairs. Because the male-male tandems occurred during mate-guarding and because tandems do not follow courtship of the intruder by the resident, this rare behavior is interpreted as a form of mate guarding rather than misdirected mating behavior.

Zhu, H.-q. ; Han, F.-y.
Cercion yunnanensis spec. nov., a new damselfly from Yunnan, China (Zygoptera: Coenagrionidae)
pp. 163-166.

Both sexes are described, illustrated and the new sp. is compared with Coenagrion impar Needham. Holotype male, allotype female: China, Yunnan prov., Zong-dian, 29-VII-1998, deposited at Shanxi University; paratypes of both sexes from same locality and date, deposited at Dali Teachers Training School, Dali, Yunnan, China. This is the eighth member of the genus known from China. The transfer of Coenagrion impar Needham to Cercion is suggested.

Kinvig, R. G.; Samways, M. J.
Conserving dragonflies (Odonata) along streams running through commercial forestry
pp. 195-208.

Commercial afforestation of natural ecosystems is increasing worldwide. There is little information however, on the extent to which biodiversity is being affected by this practice. This is especially so for stream fauna, including the conspicuous Odon. Some dragonflies and damselflies may decline when their natural environment is anthropogenically changed and, as a group, they are sensitive to the impact of afforestation. The sites were four pine plantations in KwaZulu-Natal, South Africa. 14 environmental factors were recorded along stretches of streams running through each of the four sites. The diversity of Odon. spp. and their abundances along these streams were measured. There was a strong positive correlation between certain abiotic factors, for example, boulder cover and shade, with the local distributions of these insects. Water pH was also a strong correlate. Most spp. required both unpolluted water and a sunlit stream. Particular vegetation type and exact distance of pine trees from the water’s edge (so long as they did not shade the stream) were not strong correlates. This meant that species diversity dropped dramatically where the water was completely shaded by a closed canopy, whether it was from natural forest or from exotic trees. It is recommended that no plantation trees should shade a stream edge, and should be planted at least 30m from the water. All highly invasive, dense-canopy weeds, especially Acacia mearnsii, should be removed, and extensive and intensive cattle trampling of the banks avoided.

Mahato, M.
Resource partitioning among larvae of six coexisting odonate species of the Kali Gandaki River, central Nepal (Anisoptera)
pp. 209-223.

Odon. larvae were collected from 50-1190 m elevation in central Nepal’s Gandaki River from 1984 to 1986. Resource partitioning among coexisting odon. spp. at high (>500m) and low (<500m) elevations was investigated by examining their gut contents. At both elevations, diet differences between Anisogomphus occipitalis and Davidius sp. were statistically significant. A. occipitalis ate mostly midges whereas Davidius sp. ate mayflies and caddisflies as well as midges. At low elevation there was no diet difference between A. occipitalis and Paragomphus lineatus nor between the libellulids Crocothemis servilia and Trithemis festiva. Analyses of niche breadths indicate overlap between Davidius sp., Macromia moorei, C. servilia, and T. festiva, and between A. occipitalis and P. lineatus. Significant diet differences in both A. occipitalis and Davidius sp. between low and high elevations may indicate negative interactions in the presence of other coexisting species at low elevation. Similarly, at low elevation both spp. have a narrow niche breadth, a low average number of prey items per gut, and also more empty guts than at high elevation. Mean body weights of studied odon. were relatively higher at lower elevation than at higher elevation. Predatory interactions seemed to be of little or no importance in structuring this lotic odon. assemblage, in contrast with lentic Odonata in other studies.

Vick, G. S.
Mesumbethemis takamandensis gen. nov., spec. nov., a new genus and species of the Tetrathemistinae from Cameroon, with a key to the African genera of the subfamily (Anisoptera: Libellulidae)
pp. 225-237.

The new sp. is described from a single male from Cameroon (South West Prov., Manyu, Takamanda Forest Reserve, Assam, 06degree01’N, 09degree18’E, alt.140 m, 20-II-1998). The holotype will be deposited in the collection of the Natural History Museum (London). The justification for the placement of the new genus in the Tetrathemistinae is presented. Because of the combination of characters of wing venation which it possesses, the new sp. does not fit into any existing genus and the new genus Mesumbethemis is erected to accommodate it. The unique shape of the anal appendages and the accessory genitalia can at this stage also be regarded as characteristic of this presently-monotypic genus. A key to the African Tetrathemistinae genera is provided.

Carvalho, A. L.
Descriptions of the last instar larva and some structures in the pharate male adult of Praeviogomphus proprius Belle, 1995, with notes on the occurrence and taxonomic status of the species (Anisoptera: Gomphidae, Octogomphinae)
pp. 239-246.

The ultimate instar larva, as well as wing venation and male secondary genitalia of a pharate adult, assigned to P. proprius, are described and figured, based on material from Teresopolis, Rio de Janeiro State, Brazil. Some notes on the collecting site are provided. The taxonomic status of the sp. and the geographic distribution of the Octogomphinae are evaluated.

Costa, J. M.; Santos, T. C.
Neocordulia mambucabensis spec. nov., a new dragonfly from Rio de Janeiro Brazil (Anisoptera: Corduliidae)
pp. 247-253.

The new sp. is described and illustrated and its affinities are discussed. Holotype male, allotype female: Brazil, Rio de Janeiro, Serra da Bocaina, Rio Mambucaba, 22-XI-1979; deposited at MNRJ, Rio de Janeiro. The known spp. of the subgenus Neocordulia are keyed.

Daigle, J. J.; Tennessen, K. J.
Heteragrion cooki spec. nov. from Ecuador (Zygoptera: Megapodagrionidae)
pp. 255-259.

The new sp. is described from Ecuador (holotype male: Pichincha Province, Hotel Tinalandia, 31-I-1997; allotype female: Pichincha prov., Rio Palenque Biological Station, 9-X-1988; both deposited in FSCA). Males can be distinguished by the very large decumbent tooth on the cercus.

Gonzalez-Soriano, E.; del Pilar Villeda-Callejas, M.
Ophiogomphus purepecha spec. nov. from Mexico (Anisoptera: Gomphidae)
pp. 261-266.

The new sp. is described, illustrated and compared with O. arizonicus Kenn. Holotype male: Michoacan state, Los Azufres, Arroyo San Pedro, 4 km NW of San Pedro Jacuaro, alt. 2295 m, 29-XI-1998; allotype female, same data, but 18-XI-1989; deposited at CNIN, UNAM, Mexico. Its discovery in central Mexico represents a notable southern extension of the range of this genus in America.

von Ellenrieder, N.; Muzon, J.
Description of the last instar larva of Erythrodiplax nigricans (Rambur) (Anisoptera: Libellulidae)
pp. 267-272.

The larva is described and illustrated, based on Argentinean specimens. Larval structural features of 14 Erythrodiplax spp. are reviewed.

Cordoba-Aguilar, A.
Reproductive behavior of the territorial damselfly Calopteryx haemorrhoidalis asturica Ocharan (Zygoptera: Calopterygidae)
pp. 295-305.

The reproductive behavior of C. h. asturica is described. Males fought with each other for the possession of territories which contained the oviposition resource required by females. Females arrived at territories and either copulated and left the territory, copulated and oviposited in that territory or oviposited without a preceding copulation with the territorial male. Territorial males seemed to have a higher mating success than nonterritorial males. Males carried out courtship displays before and after copulation until females finished oviposition. Copulation was divided in two stages which were characterized by the nature of the male’s abdominal flexions. The number of abdominal flexions during stage I and II was 50.2 +- 7.2 and 54.5 +- 16.7 (mean +- s.d.) respectively. The sexual behavior of both sexes is discussed under current knowledge of sexual selection studies in Calopterygidae.

Watanabe, M.; Taguchi, M.
Behavioural protandry in the damselfly Mnais pruinosa costalis Selys in relation to territorial behaviour (zygoptera: Calopterygidae)
pp. 307-316.

The reproductive strategy of the male M. p. costalis can be defined as an attempt to maximize the number of females mated. Males exhibit wing colour dimorphism: one form has orange wings, and the other has hyaline wings which resemble female wings. The former is usually territorial and the latter uses sneaky mate securing tactics around the territories of orange-winged males. Although the length of the emergence period varied from year to year, no evidence of protandry was observed. Studies over 10 years have shown that if the length of the sexually active period in females is stable, the orange-winged males should become sexually mature before females do to achieve maximal reproductive success. On the other hand, the hyaline-winged males do not mature before females due to the fact that they utilize the territories of orange-winged males. This study shows that behavioral protandry should be considered a reproductive strategy of the orange-winged males for establishing territories.

Bede, L. C.; Piper, W.; Peters, G.; Machado, A. B. M.
Phenology and oviposition behaviour of Gynacantha bifida Rambur in Brazil (Anisoptera: Aeshnidae)
pp. 317-324.

On 2 evenings in late Oct. 1999 several females were observed laying eggs in almost dry mud and sand and under mosses, within a temporary pond system, surrounded by rain forest, nr Tiradentes, Minas Gerais, Brazil. The ponds are filled with water during the rainy season (Oct. – March) but dry up entirely by the end of the dry season (Aug. – Sept.). Data compiled from field records, odonatological collections and literature showed that in Brazil G. bifida stays on the wing throughout the year. Apparently, the sp. possesses a univoltine life cycle with 2 generations of larvae, one during the warmer rainy season and another in the early dry season (Oct./Nov. – Jan./Feb. and Feb./March – May/June, respectively). Mud attached to the terminal abdominal segments of female specimens in odonatological collections was used as an evidence of an oviposition mode comparable to that observed in the field.

Daigle, J. J.
Metaleptobasis mauffrayi spec. nov. from Equador and Peru (Zygoptera: Coenagrionidae)
pp. 325-328.

The new sp. is described from Ecuador (holotype male: Napo Province, Parque Nacional Yasuni, July 1996; allotype female: Napo Province, Parque Nacional Yasuni, November 1997; both deposited in FSCA, Gainesville, FL, USA). Males can be distinguished by the long cerci, subequal to epiprocts.

Martens, A.
Group oviposition in Coenagrion mercuriale (Charpentier) (Zygoptera: Coenagrionidae)
pp. 329-332.

Pairs aggregate during oviposition. Discrimination experiments with pairs of floating leaves of Berula erecta show that tandems land preferentially on leaves where a single motionless male in the typical vertical position of a tandem male is present.

Capitulo, A. Rodrigues
Population dynamics of larval stages of Tauriphila risi Martin and Erythemis attala (Selys) in Punta Lara gallery forest, Buenos Aires, Argentina (Anisoptera: Libellulidae)
pp. 333-340.

Larval populations of the 2 spp. were studied in a lentic freshwater environment. 13 larval instars were recognized from plots of head width and length of wing-pads. Density, population dynamics, age structure, flying period and winter quiescence were analysed. Both uni- and semivoline individuals were found. Microhabitat differences were found between the 2 spp, T. risi preferring Pistia stratiotes and Hydrocotyle ranunculoides, whereas E. attala preferred lemnaceas. A life table was constructed for T. risi, which showed mortality rate maxima at hatching and at 10 and 23 months.

Babu, B. Suri
Description of the larva of Neurothemis intermedia (Rambur), with notes on biology (Anisoptera: Libellulidae)
pp. 341-346.

The morphology of the final instar larva is described and illustrated, based on exuviae and larvae from Sagar, Madhya Pradesh, India. Notes on the larval habitat, life history pattern and emergence are added.

Von Ellenrieder, N.
Aeshna tinti spec. nov. from Chile and redescription of A. elsia Calvert (Anisoptera: Aeshnidae)
pp. 347-358.

A. tinti sp. n. is described and illustrated from the Chilean Tarapaca and Antofagasta regions (holotype male and allotype female: Chile, Antofagasta, El Loa prov., Tilopozo, 23degree49’S 68degree15’W, I-1996; deposited at MLP, Argentina). A redescription and drawings of A. elsia Calv. are provided, as well as a comparison of the new sp. with all the sympatric Aeshna spp.

Wazalwar, S. M. ; Tembhare, D. B.
Innervation of mouthpart sensilla in the dragonfly Brachythemis contaminata (fabricius) (Anisoptera: Libellulidae)
pp. 359-364.

Neuroanatomical studies demonstrate single dendritic innervation of trichoid sensilla, basiconic sensilla and microtrichia, and multidendritic innervation of the papillae and sensory pegs. These sensilla can therefore be considered as mechano- and chemo-receptors respectively. The campaniform sensilla are innervated by several dendrites and many function as proprioceptors. No innervations of the spines, teeth, hooks and acanthae was observed suggesting non-sensory nature.

Zhu, H.-Q.; Ou-Yan, J.
Coenagrion bifurcatum spec. nov., a new damselfly from Heilongjiang, China (Zygoptera: Coenagrionidae)
pp. 365-368.

The new sp. (holotype male and allotype female: Mao-er shan, Dong-ling, Heilongjiang, China, 15-VII-1999; deposited at Heilongjiang Nonken Teachers’ College, Achen) is described, illustrated and compared with hylas.