Three new libelluline dragonflies from southern Venezuela, with new records of other species (Odonata: Libellulidae)

Abstract Elasmothemis rufa sp. nov. (holotype: Venezuela, Amazonas, Río Cataniapo), Macrotbemis taurepan sp. nov. (holotype: Venezuela, Bolívar, El Paují), and Oligoclada garrisoni sp. nov. (holotype: Venezuela: Amazonas, San Fernando de Atabapo) are described and illustrated. All holotypes are deposited at MIZA. Macrothemis heteronycha and Micrathyria paruensis are recorded from Venezuela for the first time, and Micrathyria dunklei for the second. Some of their features are illustrated. Distribution maps of all these species are also presednted.


INTRODUCTION
Some unidentified libelluline dragonflies from southern Venezuela, which for many years remained unexamined in a box, together with a few more recently collected and also undetermined specimens, were finally examined and identified. Most of them showed to be either new to science or first records for Venezuela. METHODS Wing vein nomenclature follows Riek & Kukalova-Peck (1984). Right wing features are given in parentheses, if differing from left wing; same for other paired structures, viz. cerci. Cux = cross-veins in the cubital space; if only one vein present, this being CuP. Length of pterostigma refers to costal length of forewing pterostigma. Length of hindwing includes only membranous part, excluding root. Total length includes cerci, length of abdomen does not. All dimensions are given in millimeters. Drawings were made using a camera lucida coupled to a Wild M-8 stereoscope. All specimens are deposited in the Museo del Instituto de Zoologia Agricola "Francisco Fernandez Yepez" (MIZA), Facultad de Agronomia, Universidad Central de Venezuela, Maracay, Venezuela. Etymology Elasmothemis rufa sp. nov. (Figs 1,2,3) 'Rufa' (Latin) means red, referring to the bright red male abdomen.

Description of male holotype
Head: Labium yellow brown, labrum and face (except for yellow anteclypeus), frons above, vertex and occipital triangle bright orange; vertex bi-tuberculate; rear of head orange brown with yellow spot behind compound eye at about half its vertical extension; antenna brown. Thorax: pale brown ochreous, but pronotal hindlobe and mesepisternum orange; traces of narrow yellow cross-band in front of metathoracic spiracle, and some yellow also along distal dorsal angle of metepimeron. -Legs dark red brown, proximal portion of femora paler. -Wings very slightly smokey with yellow tinge at extreme base, especially in cubital space; extreme wing tips (marginal cell row) brown, membranula grey brown. Main veins basally red, becoming darker towards a b nodus and beyond; pterostigma brown. 12.5 Ax in Fw, 9 in Hw; 10 Px in all wings, except left Hw (9); Fw with 2 (1) Cux, Hw with 3 (2); Rspl in Fw with 2 doublecells, Hw with 1 (0). Abdomen: Uniformly bright cinnabar red, except for S1 and S2, and proximal portion of S3, which have some yellow laterally; median transverse carina and lateral carina of S3 red, lateral carina of remaining segments narrowly black. Cercus in lateral view little slanting, its ventral surface bearing 11 (10) irregular teeth (Fig. 1a); cerci in dorsal view convergent rearwards, apical spines of cerci parallel (Fig. 1b); epiproct (Fig. 1c) reaching to ¥s of the distance between last tooth and tip of apical spine of cercus. Hamulus slightly surpassing tip of anterior lamina, genital lobe broader than half of hamulus at base (Fig. 1d). Dimensions: Total length 43.0; abdomen 27.0; cercus 2.0; Hw 32.0; pterostigma 3.5.

Diagnostic remarks
The new species can be separated from E. cannacrioides Calvert, 1906 (Figs 2d-f) by its uniformly bright cinnabar red abdomen. The lateral carina on distal half of 53 is always red in the new species, but black in E. cannacrioides. This latter species also lacks any yellow at wing bases. Structural differences in either wing venation, genital armature or caudal appendages were not observed, although the pair of dorsomedian processes (dp) of the distal penis segment (Figs 2b, e) tends to be narrower in the new species. In Venezuela populations of E. cannacrioides from north of the Orinoco river differ somewhat from populations south of it: Southern males usually have 12.5 or more Ax in Fw and 10 Ax in Hw, whereas males from north of the Orinoco more often have only 11.5 Ax in Fw and 9 or less Ax in Hw. Furthermore, southern males have strongly contrasting abdominal pattern of ochreous and ferruginous with black, while northern males show a more uniform, vermilion abdomen (De Marmels 1989). Macrothemis heteronycha (Calvert, 1909)  In the same paper, these authors present figures of the penis and hind femur of a male from southern Brazil. The Venezuelan male differs from this and other described specimens (Calvert 1909, sub Brechmorhoga;Ris 1913, sub Gynothemis) in having only nine spines in the outer row of both hind femora (Fig. 4b). The lateral lobe of penis is straight in the Venezuelan male (Fig. 4g), but curved dorsad apically in the male illustrated by Garrison & von Ellenrieder (2006: fig. 35). Claws of second and third tarsi are asymmetrical, as described by these authors, i. e., the outer claw being shorter than inner claw, and with tooth longer than tip. There are 9.5 (8.5) Ax in Fw, 7 Ax in Hw; 5 Px in Fw, 6 Px in Hw; arculus slightly distally of 2nd Ax in Fw, more so in Hw; all triangles free, subtriangle in Fw two-celled (free); discoidal field in Fw two-rowed, only slightly narrowing near anal border of wing, in Hw beginning with two cells, of which the distal one is the only entire cell between MA and MP; Rspl in Fw enclosing 5 (6)  The Taurepan is a local section of the Pem6n Amerindian tribe. The name is here used as a noun in apposition.

Description of male holotype
Head: Labium yellowish, lateral lobes narrowly orange along anterior and mesal margins, median lobe brown posteriorly; labrum orange, clypeus brown, vertical portion of frons orange laterally and narrowly along fronto-clypeal suture, remainder of frons, vertex and antenna shiny black; occipital triangle dark brown, rear of head yellow brown. Thorax: Mesepisternum shiny black, pale antehumeral stripes rudimentary, commashaped and confined to lower fourth of sclerite, but transverse bar below antealar carina greenish white; median carina black with extreme dorsal edge of proximal two thirds of its length narrowly white; lateral parts of pterothorax brown black with greenish white marks as illustrated (Fig. Sa). -Legs pale brown, tarsi black; hind femur with 10 (11) sharply triangular spines (Fig. Sb); tip of claws of fore tarsus little longer than respective inferior tooth, mid and hind tarsi have longer inferior tooth at outer claw, and inferior tooth of same length as tip on inner claw. -Wings hyaline with a very weak yellowish tinge in discal area; venation black, pterostigma dark brown, membranula grey brown. 11.5 (10.5) Ax in Fw, 7 in Hw; 7 Px in all wings, except in left Fw (6). Arculus at 2nd Ax in Fw, more distally in Hw; all triangles free, subtriangle in Fw free (two-celled), Rspl enclosing 6 cells in all wings, except for right Hw (7); Mspl absent; anal loop enclosing 12 (11)

Descriptive notes
An immature male, which differs from the holotype in having a yellow spot also on metakatepisternum above coxa, and a yellow lateral streak in basal half of 52 and 53, as well as a very tiny yellow lateral line on 56. Tip of epiproct is only one sixth as broad as maximum width at base; there are no teeth on cercus, but two minute, black tubercles near ventral angle (Fig. 8b ). Secondary genitalia as illustrated (Figs 8c-e). Dimensions: Total length 27.7; abdomen 17.5; cercus 1.2; Hw 20.0.

Remarks
The single specimen had been stored since 1983 in the 'unidentified species box' at MIZA. After the original description of M. dunklei by Westfall (1992) based on material from Brazil (Rondonia State), Paulson (2001) produced the first Venezuelan record, also from the Amazonas State, but more to the east than the present locality (Fig. 7).  Geijskes, 1963 (Figs 7, 9) Specimens examined

Remarks
All three males correspond well with the original description by Geijskes (1963) of the type series from Brazil, near the border with Surinam. Here I illustrate the penis of a specimen from Venezuela (Figs 9a, b). The present record is the first of M. paruensis from this country. I dedicate this species to Rosser W. Garrison not only for his outstanding contributions to odonatology of the Americas, but also in recognition of his unselfish readiness to collaborate whenever asked for.

Paratype female
Head: Frons and vertex pale brown, each with only basal stripe darker with some metallic blue reflections; occipital triangle yellow without any kind of processes. Other features as in male. Thorax: Dark brown with yellow markings (Fig. 10f). Legs as in male. Wings hyaline with pale amber clouding in subcostal and cubital spaces; pterostigma pale yellow. 8 Ax in Fw, 6 in Hw; 7 px in both wings; 12 cells in anal loop, including an accessory cell at heel in left Hw. One cell-row between anal loop and hind margin of wing, basally to level of arculus two rows. Abdomen: Sl-3 pale brown dorsally, yellowish in basal half; S4-8 pale brown dorsally, dark brown to black laterally and distally; S9 and 10 dark brown dorsally, paler laterally. Cercus little longer than SlO, dark brown and bearing an apical spine. Vulvar lamina as illustrated (Fig. lOg). Dimensions: Total length 26.5; abdomen 17.0; Hw 21.0; pterostigma 2.0.

Diagnostic remarks
In Borror's (1931) key the new species falls together with 0. stenoptera Borror, 1931 and 0. rhea Ris, 1911. It differs from 0. stenoptera in having a much shorter apical penis segment and differently shaped lateral lobes. Judging from Borror's figure 15 and illustrations kindly forwarded to me by Rosser Garrison of an Ecuadorian specimen in his collection, the genital lobe is broader and rather regularly rounded in 0. stenoptera, but narrower and slightly tapering anteriorly in 0. garrisoni. From 0. rhea the new species differs in cereal morphology. In the MIZA collection there are specimens of 0. monosticha Borror, 1931 and of 0. sylvia (Kirby, 1889) from San Fernando de Atabapo, the latter species also from the Rfo Sipapo. AcKNOWLEDGEMENTS I thank Rosser W. Garrison, Sacramento, for sending me figures of a male 0. stenoptera in his collection. To Quintin Arias I am indebted for scanning and editing the figures. Finally, I wish to thank Rosser Garrison, Natalia von Ellenrieder and Klaas-Douwe Dijkstra for peer-reviewing the manuscript.