ALBERT

Description: Until recently biological research in the sea off Suriname had not received much attention. There was no fishery in the open sea and there was no incentive to investigate this unknown world. But in the last twenty years, experiments have gradually led to serious study of the subject. Before the second world war, schooner fishing in the open sea to catch red snapper fish, as already carried out off (British) Guyana, was tried by the Curaçao Trading Company in Paramaribo, but this experiment was not a success. During the war, a study of the local fisheries became urgent, to find out how far Suriname was able to supply the people with protein food.

Description: The genus Staurophlebia was established by BRAUER (1865, 1866) from his species magnifica from Brazil, a name which later proved to be a synonym of reticulata (Burmeister 1839), (see under this species). In his notes on St. magnifica, HAGEN (1867) said that SELYS (MS) has proposed the genus name Megalaeschna for Aeschna reticulata Burm., Ae. gigas Rbr. (= reticulata), and Ae. gigantula Selys, a closely related new species which was subsequently described by MARTIN. However, Megalaeschna is a synonym of the earlier name Staurophlebia, as already pointed out by COWLEY (1935). In his classification of the aeschnines, SELYS (1883) includes the two subgenera Neuraeschna and Staurophlebia in his genus Staurophlebia s.l., while KIRBY (1890), CALVERT (1905), and MARTIN (1909) give Staurophlebia s.str. generic rank, with St. reticulata Burm. as the genotype. The characters of this genus are as follows: Wing venation: subcosta prolonged beyond the nodus to the first or second postnodal cross vein. Median space free. Triangle long, with 6—8 cells. M2 curved upward proximal to stigma. Rs forked proximal to stigma, enclosing in its fork 3—4 rows of cells; Rspl curved, between Rs and Rspl 5—6 rows of cells at maximum. Anal loop with 12—18 cells. Anal triangle in male 3-celled. Pterostigma small, longer in fore wing than in hind wing. Large (75 mm) to very large (96 mm), stoutly built species, green, brown and blue-coloured. In general, head and thorax light-green, abdomen (except the first two segments) red-brown, bluish green, or dull blue. Frons prominent, marked with T-spot. Eyes connected for a long distance, occipital triangle small. Abdomen long-cylindrical, male with auriculae on segm. 2 and moderately narrowed at segm. 3. Male appendices superiores long, leaf-like, with a hooked middle process on upper side half-way down their length, and an erect denticulate crest at the distal end, along the inner margin. Inferior appendage long-triangular, reaching to 1/3, mostly to 2/3, the length of the superiores. There is a basal prominence of the inferior appendage just between the bases of the app. sup. in the male. App. sup. of the female lanceolate, entire. Abd. segm. 10 of female with a long, two-pronged, ventral process.

Description: This study contains the results of an examination of the Corduliidae found in the Guyanas. It is based on a critical study of the data as published mostly in the older literature and on the identification of the material brought together in Surinam in the years 1940 to 1965 by Mr. J. Belle and myself, beside some specimens picked up in French- and in (Br.) Guyana. Comparison of three types in the Selys collection in the Brussels Museum, of one in the Fraser collection in the British Museum (Nat. Hist.) in London and of one kindly received from the Museum in Berlin was necessary to eliminate further confusion. It now became clear that, so far as the material goes, one genus (here described as new) belonging to the Gomphomacromiinae and two genera of the Corduliinae inhabit the Guyanas. Among these the female allotype of Paracordulia sericea Selys is described and of the genus Aeschnosoma the male allotype of Ae. elegans Selys and Ae. auripennis as a new species in the female sex only, whereas the larva of Ae. forcipula Selys and of Ae. auripennis n. sp. are described for the first time. It is a well known fact that the Corduliidae are poorly represented in South America, in contrast with North America and the Old World, where they are represented by numerous genera and a great number of species. In his well known work on the Odonata in Biol. Centr. Am. (1892-1908), Calvert states the practical absence of this group in the present fauna. Ris (1918) arrives to the same conclusion in his study on the Odonata of the South American Cordilleras, when he says that the Corduliidae in that region are very poorly represented in comparison with the other families. Cowley (1934) mentions that among 700 specimens of dragonflies, received from Perú, there was but one Corduline. In our collection of about 20,000 specimens of Odonata from Surinam, the total number of Corduliidae imagines amounts to no more than 50, that is 0.2%.

Description: (1) Faunistic insect collecting was done in Suriname from September 1963 to December 1964 with two types of “malaise” traps. (2) Trapping was practised on nine localities in different habitats, operating from the seacoast near Paramaribo via the older coastal belt and the savanna region into the rainforest of the hilly interior. (3) During this operation, a total of about 90.000 insects was collected. There was but little variation in the proportions of the different orders of insects taken in the nine localities. This is explained by the mode of sampling. (4) The catches show the following relative abundance: Diptera 1/2, Hymenoptera 1/5, Lepidoptera 1/7, Coleoptera 1/20, Hemiptera 1/40, Orthoptera 1/50, others less than one percent. (5) The variation within the orders was: Diptera 36—72%, Hymenoptera 11—33%, Lepidoptera 8—37%, Coleoptera 1—11%, Hemiptera 1/2—9% and Orthoptera 1—4%. (6) Most of the collected insects belong to dayfliers, i.e.: Diptera, most of the Hymenoptera (Aculeata), Lepidoptera Rhopalocera and Odonata. Other species collected are active at night. The moths and micro’s were represented 10 times as many as the Rhopalocera, but the Nematocera formed only 1/6 of the Diptera. Among the flies 1/5 belonged to the Tabanidae.

Description: Of the three Guyanas on the north coast of South America, Suriname is the middle one, lying between French Guyana to the east and British Guyana to the west. The frontiers between these three countries are formed by the Marowijne River (Suriname — French Guyana) and the Courantyne River (Suriname — British Guyana). In general the Guyanas are much alike in geographical features — covered with tropical rain forest for the most part and with savannas and swamps for the rest. The freshwater molluscs live in the large rivers and the bush creeks in the hinterland, and in the swamps, canals and trenches in the more or less cultivated coastal plain.

Description: Of the American species of Anax characterized by an unmarked frons, A. longipes Hagen (1861) was described from U.S.A. and A. concolor Brauer (1865) from the Amazon in Brazil. But soon after their description HAGEN (1890) was of the opinion that concolor Brauer was only a variety of longipes, in which according to him the odonatologists have taken the same stand. This conception is probably due to the fact that insufficient material of both species is studied. The motive for a reexamination of the two species was a comprehensive material of Anax concolor mostly collected in Suriname and on the Lesser Antilles. Additional specimens of A. longipes from the U.S.A. were received for comparison. The type specimens of both species could be examined but the difficulty was that the types of both species belong to different sexes. New descriptions of the imagines and of the larvae in their last instar are made, with a comparison of the most striking differences between the two species. Beside the morphological points of controversy in both imagines and larvae, there proved to be also a marked difference in their distribution: A. longipes occurs in U.S.A. entering Mexico, the Greater Antilles and Bahamas, while A. concolor occupies tropical South America to the Lesser Antilles and the Bahamas, and Central America. This study has demonstrated that Anax concolor is not a variety of A. longipes, but that both forms belong to different species.

Description: Single female specimens of dragon flies are often difficult to identify owing to the fact that, when they are known at all, the descriptions are incomplete and mostly lack the essential figure of the genitalia. The following are descriptions of the unknown females of five species, the males of which have been known for the last eighteen to fifty years. They are all complete with figures of the genitalia. The material from which the descriptions have been made has been accumulated during many years of collecting. I am indebted to Mr. J. BELLE, Paramaribo, who was kind enough to place at my disposal, for description, some of the unknown females collected by himself.

Description: In the following descriptions, three new species of Micrathyria are introduced. They have been collected during the last twenty-three years of field work carried out in Suriname from the country’s northern Atlantic coast to its southern border with Brazil. Micrathyria surinamensis n. sp. belongs to the aequalis-longifasciata group, M. paruensis n. sp. is a representative of the ungulata-complex and M. coropinae n. sp. shows a close relationship with M. romani Sjöstedt. I am much indebted to Dr. RENÉ MALAISE, Curator of the Naturhistoriska Riksmuseum, Stockholm, for the loan of the type specimen of M. romani, from which supplementary notes and figures could be made.

Description: 1. Inleiding. 2. Verloop van de expeditie. 3. De voorbereidingen en de reis naar de Nickerie rivier. 4. De tocht op de Nickerie rivier (27 jan.-22 febr.). 5. De tocht op de Maratakka rivier (25 febr.-9 mrt). 6. Het verblijf te Wageningen en in Nw-Nickerie, met het onderzoek van de Nannikreek (10-21 mrt.). 7. De tocht op de Corantijn, in de Kaboerikreek en in de Kabalebo rivier (22 mrt.12 april). 8. De terugtocht. 1.\nINLEIDING\nDe zo\xc3\xb6logische expeditie naar het Westen van Suriname in het voorjaar van 1971 uitgevoerd, werd door het Rijksmuseum van Natuurlijke Historie te Leiden georganiseerd en door de Stichting Wotro in Den Haag gesubsidieerd*). Zij werd gehouden van 19 januari tot eind april 1971. Van het museum te Leiden namen aan de tocht deel de leden: Dr. D. C. Geijskes (leider en entomoloog), Dr. M. Boeseman (ichthyoloog) en P. Staffeleu (technisch assistent A) voor het verzamelen en prepareren van zoogdieren en vogels. Te Paramaribo sloot zich daarbij aan D. G. Reeder, onderopzichter bij \'s Lands Bosbeheer, die de herpetologie (Amphibia, Reptilia) voor zijn rekening nam en ook botanisch verzamelde.\nHet doel van de expeditie was het verzamelen van dieren in het gebied van de Nickerie rivier, de Maratakka, het Nannibekken en een gedeelte van de Beneden Corantijn, inclusief de Kaboerikreek en de Kabalebo rivier tot aan de Avanavero-vallen. De aanleiding hiertoe was, dat ten eerste over dit

Description: (1) Faunistic insect collecting was done in Suriname from September 1963 to December 1964 with two types of \xe2\x80\x9cmalaise\xe2\x80\x9d traps. (2) Trapping was practised on nine localities in different habitats, operating from the seacoast near Paramaribo via the older coastal belt and the savanna region into the rainforest of the hilly interior. (3) During this operation, a total of about 90.000 insects was collected. There was but little variation in the proportions of the different orders of insects taken in the nine localities. This is explained by the mode of sampling. (4) The catches show the following relative abundance: Diptera 1/2, Hymenoptera 1/5, Lepidoptera 1/7, Coleoptera 1/20, Hemiptera 1/40, Orthoptera 1/50, others less than one percent. (5) The variation within the orders was: Diptera 36\xe2\x80\x9472%, Hymenoptera 11\xe2\x80\x9433%, Lepidoptera 8\xe2\x80\x9437%, Coleoptera 1\xe2\x80\x9411%, Hemiptera 1/2\xe2\x80\x949% and Orthoptera 1\xe2\x80\x944%. (6) Most of the collected insects belong to dayfliers, i.e.: Diptera, most of the Hymenoptera (Aculeata), Lepidoptera Rhopalocera and Odonata. Other species collected are active at night. The moths and micro\xe2\x80\x99s were represented 10 times as many as the Rhopalocera, but the Nematocera formed only 1/6 of the Diptera. Among the flies 1/5 belonged to the Tabanidae.