Hydrophylax aquivolans. New species. ♀ length .6 mm. Length of fore wing .69 mm. ; hind wing .45 mm. (Fig. 1.) General color light brownish yellow. Legs and antennae paler. Head seen from above gently concave in front and behind, sparsely clothed with a few stiff setae. Thorax smooth, clothed with stronger setae. Scutellum gently rounded behind. Postscutellum with two fine setse, close together on each side. Propodeum smooth, without setse except near the spiracles. Metathoracic spiracles enlarged, with two short, knobbed hairs which appear to arise within the opening.
Abdomen conic-ovate, sparsely clothed with long stiff setas, broadly joined to the thorax; 5 visible dorsal segments; length of abdominal segments in the ratio of 5, 2, 2, 2, 3. Ovipositor exserted about the length of the shortest abdominal segment.
Antennae 8-jointed, consisting of scape, pedicel, 1 ring joint, 2 funicle joints and a 3-jointed club. Scape compressed, elongate-oval; pedicel as long as the first joint of funicle and ring joint, elongate-obconic ; first funicle joint cylindrical, 11/2 times as long as the second ; second slightly oval ; club elongate- oval, 1-5 longer than the funicle. Anterior and middle femora slightly enlarged medially, the posterior femora more distinctly enlarged. Anterior and middle tibiae of about same width throughout. Posterior tibiae somewhat enlarged distally and slightly narrowed just before the tip. First and second posterior tarsal joints of equal length, the third somewhat shorter.
Front wings very narrow, 20 times as long as broad. Mar- ginal cilia very long and evenly spaced, those on the posterior margin four times as long as the wing is wide. Marginal cilia are interspersed with a submarginal row of short setae.
♂ Length .6 mm. Similar to the female. Antennae 8-segmented, consisting of a scape, pedicel, a ring joint, 5 funicle joints, the last three more closely united. Scape compressed; pedicel obconic; ring joint distinct; first funicle joint about11/2times longer than second, thicker at base than apex. The remaining joints sub-equal in length, the last two thicker than the preceding. Apical joint pointed at tip. Antennae clothed with stiff setae, which are longer than those of the female.
