TWO NEOTROPICAL AGRIONINE DAMSELFLIES (ODONATA) FROM MTS. DUIDA AND
RORAIMA
Author
Needham, James G.
Author
Fisher, Elizabeth
American Museum Novitates
1081
no.
1
3
July 17, 1940
AMERICAN MUSEUM NOVITATES Number 1081 Published by THE AMERICAN MUSEUM OF NATURAL HISTORY New York City July 17, 1940
TWO NEOTROPICAL AGRIONINE DAMSELFLIES (ODONATA) FROM MTS. DUIDA AND RORAIMA
James G. Needham and
Elizabeth Fisher
The species here described were collected by Dr. J. G. Myers in 1932. Both are
important additions to the known American odonate fauna. One represents a new genus,
whose nearest relative is the African genus Phaon. The other is not entirely new,
but is the male of a puzzling genus that has hitherto been known from a single
female specimen in the American Museum collection, that was described by the senior
author in these Novitates.
We now have adequate material for illustrating the adults of both genera, but
knowledge of the immature stages is still wholly lacking.
IRIDICTYON
Iridictyon myersi
new species
Length of abdomen:♂ 51-53 mm.; ♀ 52. Hind wing: d\ 39-41; 9, 52.
This is a very beautiful slender, bronzy green and black species with
delicately tinted iridescent wings. Head green on face and dorsum and
clothed with black hairs. Ocelli yellowish; eyes and antennae fuscous:
rear of head and underside including mouth-parts black.
Sides and dorsum of the entire thorax shining bronzy green with
sutures and carinae margined by black. The black hairs that thinly
clothe the front are longer than those on the face. Under parts of
thorax black, becoming pruinose in old males.
Legs long and slender, uniform black. Spines of the femora and tibiae
very long and thin and numerous. Tarsi clothed with short close
pubescence. Hind tibiae 9 mm. long, strongly bowed outward; middle and
front tibiae less bowed and a little shorter. Claws with a very minute
tooth beneath very near the tip.
Wings hyaline with black veins, the membrane with iridescent violet
reflections. A very narrow border of fuscous tinges the rear margin of
the wing. Antenodal veins about 60 in the fore wing. There are about
seven crossveins in the quadrangle.
Abdomen black except for the dorsum of the first segment, which is
shining bronzy green washed lightly with gold. The dorsum of the second
segment has strong violet reflections, and there is a tinge of the same
color on the black of the slightly enlarged terminal segments. Segment 2
is hardly as thick as 1, and only a little thicker than the four
segments that follow it. The relative length of segments 7 to 10 is
about in the ratio of 10:6:4:3, and the appendages are about as long as
the 9th segment. Segment 10 is slightly carinate above in its apical
half, and slightly so each side opposite the base of the inferior
appendages.
The superior appendages of the male are sub-clavate as viewed from
above and incurved, with a few rather strong spines on the outer side of
the curve and with a tuft of black hairs at the tip. In lateral view
they are obclavate, somewhat regularly narrowed outward from a
Fig. 1.
Wings of Iridictyon myersi.
Fig. 2.
End of abdomen of the male, viewed from the
side.
Fig. 3.
Superior appendage in oblique upper and lateral
view.
Fig. 4.
End of abdomen of female of same in lateral
view.
Fig. 5.
End of abdomen of male of Rimanella arcana in lateral
view.
Fig. 6.
Penis of the same.
broad base almost to the somewhat knobbed tip. The tip
bears a minute longitudinal carina above. The inferior appendages are
broad at base, laterally compressed there, straight thence outward and
almost parallel sided to their slightly incurved tips.
Female.—Similar in coloration of body and legs, but the wings are lightly tinged with
fuscous throughout most of the membrane, and crossed by an oblique band
of milky white color just beyond the nodus. This band ends on the tips
of veins M3 and M4. Segment 10 is half as long as 9, and bears three
sharp terminal spines at the end of the mid-dorsal and lateral carinae.
The rather stout appendages are about as long as 10 and taper to a sharp
point. The palp is about as long as the ovipositor is wide.
Types.—A single pair,
♂ No. 3043 and ♀ No. 3040, type and paratype, respectively, from the
Ireng River, Paka-raima Mountains,
British Guiana
A cf1 No. 3111 from
Mazaruni Hd
and another d71 from
Mt. Roraima
paratypes, from the same mountains. Dr. J. G. Myers, collector.
Rimanella arcana
Needham
Needham, 1933, Amer. Mus. Novitates, No. 664, pp. 3-5, female only
(as Rima arcana).
Needham, 1924, Entomological News, XLV, p. 50 (name changed to
Rimanella).
Male.—Length, 48-49 mm. Abdomen, 37-38 mm.; hind wing, 29 mm.
Color dull greenish black and brown. Head, thorax and legs as described for the female. Labrum greenish yellow with a median brown spot on its anterior margin.
Wings hyaline. Postnodal crossveins 14-20 in the fore wings, and 14-17 in the hind wings; the first and second series not matching in either fore or hind wings.
Abdomen dull reddish brown with the greenish black above confined to segment one, the apices of two to seven, eight except for a narrow basal pale ring, and all of nine; ten pale. The penis as in figure 6 is non-lestid in form. Terminal appendages reddish brown, black at their apices; inferiors rudimentary; superior much longer than the tenth segment (figure 5).