Harvard University. Museum of Comparative Zoology.

Needham, James G. (James George), 1868-1956.

American Museum of Natural History Scientific Publications

56.57,33A(78.8)Article VI.- SUPPLEMENTAL DESCRIPTIONS OF TWO NEWGENERA OF AESCHNINXE.BY JAMES G. NEEDHAM.When Professor Cockerell was collecting fossils at Florissant he wroteme of the discovery of the Litheschna described in the foregoing pages, andsent me a sketch of its venation. Having in my possession some unpub-lished figures of related genera, I sent them to him for whatever use he.... . .-. vFig 1 Venation of Cymatophlebia longiolata Muenst.might choose to make of them. These included. a drawing of the venationof Cymatophlebia (probably the type species C. longiolata Muenst.) morecomplete than any that have been published, a drawing of the venation ofanother fossil 2Eschnine, and a photograph of a recent undescribed genutsfrom Borneo. The specimens are in the Museum of Comparative Zoologyat Cambridge, where in 1897, through the kindness of Mr. Samuel Henshawand Dr. R. T. Jackson, I had the privilege of studying them and of makingthese figures. The two last mentioned represent genera as yet undescribed.Professor Cockerell has made good use of the figures in the comparisonsof the foregoing paper, and has invited me to add descriptions of the twonew genera. Since it is desirable under the circumstances that these shouldbe made know-n, I append brief diagnoses of them, with figures, insertingmy new figure of Cymatophlebia (Fig. 1).Morbuschna gen. nov.Type, the specimen labelled Afschna muensteri Germar in the Hagen collectionof fossil Odonata in the Museum of Comparative Zoology.141142 Bulletin American Museum of Natural History. [Vol. XXIII,Only the venation of this specimen is in a sufficiently good state of pre-servation to admit of critical diagnosis. Its chief characters are shown inFig. 2, and are as follows: -Stigma with a strongly developed brace vein; ante- and post-nodals in the forewing about 12 and 10, in the hind wing about 10 and 12 respectively; arculus slightlyarcuated, especially in the fore wing, the sectors arising from it well separated andwith gentle curvature; proximal end of the bridge slightly more identified vein=~~~~~~~~~~~.).,~~IFig. 2. Venation of Morbceschna muensteri (Germar).M,+, then with vein M,; oblique crossvein 4 to 5 cells beyond the subnodus:veins M, and M, separated by a. single row of cells as far as the brace vein of thestigma (at which point they are most approximated), then diverging, with threerows between; a straightened line of crossveins one row of cells behind theradial sector, simulates a radial supplement; veins M3 and M4 are sinuated in theirmiddle course, the space between them is widened at the sinuation and narrowedagain beyond in the hind wing: no crossveins are discoverable in the super-triangle;there are two in each triangle and there are at least three cubito-anal crossveins;there are three rows of post-triangular cells, and in the hind wing there is a sinu-ous median supplement paralleling vein M4 and separated from it, first by one,then by two, then by one, and finally by three rows of cells; the branches of thecubital vein in the hind wing are separated by a single row of cells, and areapproximated beyond the level of the triangle, vein Cu, having about seven distinctstraight posterior branches extending to the hind margin; the compact anal loopconsists of four cells, and behind it are at least two straight sectors extending fromthe cubital vein to the hind margin.Doleschna gen. nov.Type, D. elacatura sp. nov.Most nearly allied to Gomphceschna. The venational characteristics of the genusare as follows: The stigma has a strong brace vein, and two additional crossveinsmeet its hind margin; ante- and post-nodal crossveins are in the fore wing 17 and8 or 9, and in the hind wing 12 and 9 respectively; the first two branches of themedian vein are most approximated at the level of the stigma, after which theydiverge to include two rows of cells to the margin; between the hinder of these andNeedham, Two New Genera of Xschnin.1the radial sector there are but two rows of cells from the upward bend to the wingmargin; the oblique vein is but little more than one cell distant beyond the sub-nodus; the last two branches of the median vein are sinuate beyond their middle,and include for a distance two rows of cells between them; a more or less distinct.median supplement parallels the hinder of these, separated from it by a single rowof cells; there are but four principal branches arising from the vein Cu2. Thearculus is somewhat angulate at the approximated origin of its sectors; theresaretwo crossveins in super triangle and in triangle in all wings, and there are twocubito-anal crossveins; there is a small anal loop, consisting of three cells, and there-are no strongly developed sectors in the anal angle behind it.A very remarkable, primitive AEschnine genus, with hemispherical head,eyes touching on the dorsal side for a little way, ovipositor arcuate and withthe abdomen curiously spindle-shaped beyond the constricted third segment.Dolasschna elacatura sp. nov.Fig. 3.Length 54 mm.; abdomen 42 mm.; hind wing 44 mm.A brown species, apparently without thoracic stripes. Eyes contiguous-M,IFig. 3. Dolceschna elacatura sp. nov.for a distance somewhat exceeding the breadth of the vertical tubercleFrons obtusely projecting, unmarked above, with an obscure transverse-ridge across its superior margin. Face receding to the mouth; labrumyellowish with brown border. Occiput naked, very narrow, and deeply-notched behind between the eyes: face and vertical tubercle pubescent.143.1907.]Bulletin American Museum of Natural History. [Vol. XXIII,with blackish hairs. Legs moderately short and slender, reddish, darkeron the knees and tarsi; claws with a very minute tooth under the middle.Wings transparent amber brown, hyaline at apex and behind triangles;stigma reddish brown.Abdomen constricted on segment 3, spindle-shaped beyond (whence thespecific name), being depressed on segments 4-6 and strongly compressedon segments 7-9; brown, with pale (bluish?) half rings bordering the middletransverse carina behind on segments 2-9, interrupted on the mid-dorsallongitudinal carina, and narrowed laterally to form paired lance-triangularspots on segments 4-7; segments 8 and 9 paler below. Segment 3, aboutas long as 1 and 2 together and slightly longer than segment 4. Segments4-6 are of equal length, and segments 7, 8 and 9 are successively a littleshorter, with segment 10 hardly half as long as segment 9, and of verypeculiar form. It is abbreviated dorsally and declined at hind margin.It is prolonged ventrally from its hind margin, and the prolongation is con-cave ventrally at base to receive the upcurving tips of the ovipositor blades;it is concave above at the tip, for the reception of the decurrent subanallobes; the latter are clothed with re-curved hairs, and the hind border ofthe prolongation of segment 10 is beset with minute denticles. The palpsof the ovipositor guides are about as long as the 10th segment and each istipped with a pencil of brown hairs of equal length; the appendages arebroken off.Type, a single female from Mindai, Borneo, in the Museum of Compara-tive Zo6logy of Harvard College.144

Two new genera of Aeschninae

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