f ittkaulus maculatus a new genus and species from northern Brazil ( Leptophlebiidae : Ephemeroptera )

A new genus and species of Leptophlebiidae, Fittkaulus maculatus, is described from male and female imagos, subimagos, and nymphs collected from streams of the eastern Guiana Shield, Para State, Brazil. Association of life cycle stages is by rearing. Fittkaulus appears to be most closely related to Terpides Demoulin.


INTRODUCTION
Recent revisionary studies of the Neotropical Leptophlebiidae (Traver 1959(Traver , 1960a(Traver , b, 1963;;Traver and Edmunds 1967;Peters 1971;Pescador 1976) have greatly increased our knowledge of the mayfly fauna of this region.There are numerous new genera and species, particularly from the warmer northern areas that still remain to be defined.Herein w~ describe a new genus and species from the mayfly collections of Dr. E. J. Fittkau.
The following terms and procedures used in the generic descriptions of the imagos and nymphs require explanation.Venational terminology used is as given by Peters and Edmunds ( 1964) .Each segment of the fore I egs of the male imagos is compared to the length of the fore tibiae and expressed as a ratio, while the average length in millimeters of the fore tibiae is given in parentheses.In the figure of the labium, the ventral surface is shown on the right hand side of the drawing, and the dorsal surface is shown on the left.
Fittkaulus, new genus  IMAGO -Length of 6 : body, 5. 0 -6.0 mm; fore legs, 4.9 -5.0 mm.Length of <i': body, 5.5 -6.8 mm; fore wings, 5.3 -6.0 mm.Eyes (Fig. 8-9): eyes of 6 meet on meson of Harry M. Savage(") William L. Peters(*) heaci, dorsally upper portion of eyes circular with large facets, dorsal portion of eyes on long stalk as in Fig. 8-9; lower portion of eyes large, bulbous.maximum width of lower portion slightly greater than length of stalk; eyes of <i ' large, separated on meson of head by a length 2 times as great as maximum width of an eye, eyes extend posteriorly beyond margin of head.Lateral ocelli enlarged.Wings Fig. 1-3): maximum width of fore wings approximately 1 /3 maximum length of fore wings; vein Rs of fore wings forked 1 /5 of distance from base to margin; vein MA of fore wings forked a little more than 1 /2 distance from base to margin, fork asymmetrical, distal portion of vein MA strongly sagged; vein MP of fore wings forked from a little more than 2/5 to a I ittle more than 1 /2 distance from base to margin, fork asymmetrical; vein 1Cu 1 attached near base to vein CuA with cross vein, remainder of cubital area as in Fig. 1; cross veins few.Hind wings small; costal projection of hind wings well developed, apex rounded, base of projection narrow, apex located approximately 3/4 distance from base to margin of wings; apex of wings obtuse, cross veins few.Legs: ratios of segments in 6 fore legs, 0.71: 1.00 (1.97 mm): 0.03: 0.23: 0.26: 0.14: 0.08.Claws of a pair similar, both apically hooked, each with an opposing hook (Fig. 5), Genitalia (Fig. 4): forceps two segmented, segment 2 of forceps 1 /8 -1 /7 length of segment 1, segment 1 basally expanded, segment 2 acute apically; maximum length of styliger plate along lateral margin approximately 1 /3 maximum width, maximum length of styliger plate along median line approximately 1 /5 maximum width, posterolateral ma1•gins developed dorsal to forceps; penes tubular, fused except for apical 1 /3, ( • l -Laboratory of Aquatic Entomology, Florida A. & M. University, Tallahassee, Florida, U.S.A., 32307. without appendages.Ninth sternum of ~ deeply cleft apically (Fig. 14).Terminal filament slightly longer than cerci.suBIMAGo -Characters similar to imago except upper portion of eyes of ~ subimago smaller, eyes of ~ subimago meet on meson of head to separated by a distance approximately 1/5 the width of an upper portion  .Fore legs and genital forceps not fully extended in ~ subimagos.Wings: membrane translucent, whitish, with long hair on apical and anal margins of fore and hind wings neither thickened nor branched.
ETYMOLOGY -The genus is named for Dr. E. J. Fittkau, who collected the specimens.TYPE SPECIES -Fittkaulus maculatus, new species.
Thorax: color and marks as in J imago, except long submedian black marks present on pronotum, and pleurae with medain longitudinal brownish-black wash form1ng a distinct stripe entire length of thorax.Wings: color and marks as in J imauo.Legs: color as in t imago, except median marks absent on segments 6 and 7 and weakly developed on other terga; color and marks of sterna as in t imago except sternum 7 with a small submedirn black circular macula.Caudal filaments pale yellow.

SUBMAGos
(in alcohol) -Characters similar to imagos except stalked turbinate portion and facets of eye of J subimago yellowish-white.Scape and pedicel yellowish- white, flagellum as in J imago.Thorax: pronotum as in J and ~ imagos; mesonotum pale yellow, with anterior, anterolateral areas and inner parapsidal suture yellowish-brown, carinae blackish-brown; metanotum as in J and ~ imagos; pleurne brownish-yellow, markings as in J and ~ imagos.Legs: legs brownish-yellow, ecxept articulations dark brown.
Association of life cycle stages is by rearing.All specimens except for the 2 nymphal paratypes from lveraca I Creek, were collected from the same locality.No differences between the nymphs from the two sites were detected.

ETYMOLOGY -
Macula, L., meaning spot, mark; in reference to the macula on the fore wings at the fork of vein MA.

mscussroN -
Fittkaulus can be distinguished from all other genera of Leptophlebiidae by the following combination of characters.In the imagos: (1) upper portion of 6 eyes is on a long stalk, facets are large (Fig. 8-9); (2) vein MA of fore wings is forked a little more than 1 /2 distance from base to margin, fork asymmetrical, distal portion of vein MA strongly sagged; (3) vein MP of fore 296 -wings is forked from a little more than 2/5 to a I ittle more than 1 /2 distance from base to margin, fork. is asymmetrical (Fig. 1); (4) hind wings are small with a well developed, long, narrow, apically rounded costal projection located aµproximately 3/4 distance from base to wing margin (Fig. 2-3); (5) basal 2/3 of penes are fused and without appendages (Fig. 4); ( 6) forceps of the 6 genitalia are 2-segmented; (7) ninth sternum of 9 has a deep V-shaped cleft apically (Fig. 14); and (8) claws of a pair are similar, both apically hooked, each with an opposing hook (Fig. 5).In the nymphs: (1) dorsal and ventral portions of gills on segments 2-6 are dissimilar, dorsal portion is large, apically truncated, with median apical projection, ventral portion is smaller, elliptic (Fig. 16); (2) glossae of the labium are curved over ventrally (Fig. 22); (3) claws are apically hooked and narrow, with a basal group of 5-6 short, subequal denticles along margin, and with a subapical group of narrow, unequal denticles set in from margin as in Fig. 18; (4) posterolateral spines are acute on abdominal segments 4-6 and 8-9, but are absent on segment 7; and (5) cerci have a row of long setae on the inner lateral margin, while the terminal.filament has long setae on both lateral margins.
Fittkaulus appears to be most closely related to Terpides Demoulin.Demoulin (1966) established Terpides based on nymphal specimens of T. guyanensis from Surinam.The imaginal description of Terpides was provided by Peters and Harrison (1974) who described T. jessiae from St. Vincent, West Indies.Fittkaulus can be distinguished from T erpides by the following combination of characters.In the imagos: ( 1) upper portion of eyes of 6 is on a long stalk, facets are large (Fig. 8-9); (2) vein MP of fore wings is forked from a little more than 2/5 to a little more than 1 /2 distance from base to margin, fork is asymmetrical (Fig. 1); (3) hind wings are small with well developed, long, narrow, apically rounded costal projection (Fig. 2-3); (4) claws of a pair are similar, both apically hooked, each with an opposing hook (Fig. 5); (5) forceps of the 6 genitalia are two segmented; and (6) ninth sternum of 9 has a deep V-shaped cleft apically (Fig. 14).In the nymphs: (1) dorsal and ventral portion of gills on segment 2-6 are dissimilar, dorsal portion is large, apically truncated, with median apical projection, ventral portion is smaller, elliptic (Fig. 16); (2) claws are apically hooked and narrow, with a basal group of 5-6 short, subequal denticles along margin, and with a subapical group of narrow, unequal, denticles set in from margin as in Fig. 18; and (3) the lingua of the hypopharynx widens distally as in Fig. 21.

BIOLOGY -
Nymphs of Fittkaulus macu/atus have been collected in streams 3-Sm wide, 20-50cm deep, with sandy bottoms and partly exposed bedrock.Most nymphs were found on leaves and other large detrital fragments in areas of slow current.A few specimens were collected from fine detritus and sand in calm areas.(Based on field notes of Dr. E. J.

Fittkau) .
This research was supported by a grant from the Cooperative State Research Service, United States Department of Agriculture (P .L. 89-106) to Florida A&M University.