Erythrodiplax melanorubra
| Erythrodiplax melanorubra | ||||||||||||
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Erythrodiplax melanorubra |
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| Scientific name | ||||||||||||
| Erythrodiplax melanorubra | ||||||||||||
| Borror , 1957 |
Erythrodiplax melanorubra is a species of dragonfly from the subfamily Sympetrinae . It wasdescribedby Donald Joyce Borror in 1942and classified in the Connata group . The larva was firstdescribedby Jorge Limongi in 1991. The species has been found in Venezuela , Colombia , Ecuador , Peru , Chile , Argentina , Bolivia , Paraguay and the Brazilian state of São Paulo .
features
Construction of the Imago
In not yet stained imagines is abdomen brown yellowish and darkens backwards. The males have brown stripes on the fourth to eighth segment on the sides just above the lateral keel. Up to the sixth segment, these strips are interrupted at the beginning of the segment. With age, the abdomen darkens in both sexes and becomes black in males, with the exception of the first two segments, which always remain brown. From the third up to the maximum of the seventh segment, the abdomen shimmers bluish. The females, on the other hand, have a more cylindrical abdomen than the males and turn dark brown to brown-black with age. As with the males, the first two segments remain brown. At just over 20 millimeters, the abdomen of the males is on average almost two millimeters longer than that of the females.
In animals of both sexes that are not yet fully colored, the trunk is initially the same color. The top is yellowish brown and the sides brownish yellow. There is also a red-brown ante - humeral stripe that becomes darker towards the front. In the females, a greenish sheen is also visible behind the stripe. A sexual dimorphism develops with age . While the males are becoming darker in color, drifting into red, reddish brown or even blackish brown, the females turn dark brownish green or dark brown.
The wings are transparent except for a spot at the base. With age, the spot in the males changes from yellowish, through a strong brown to brown-black, whereby it is always lighter in the front pair of wings than in the rear pair of wings. In the hind wing it is triangular. In females, the stain also changes color with age. At first it is yellowish to light brownish, later it becomes dark brown along the veins. In the forewing, the spot is so weak in females that it seems to be partially absent. On average, the hind wings of both sexes are around 24 millimeters long and the wing marks measure 3 millimeters.
The forehead of young animals is yellow to brown, with the females also being green-yellow and then dark brown-green on the sides. In males, the forehead turns reddish, brownish red, or very dark red with age. Sometimes there is also a bluish shimmer. In the case of females, on the other hand, only the darker side color expands.
Construction of the larva
The larvae reach lengths of 13 millimeters if the anal pyramid is taken into account. Seven millimeters of this amount to the 4.8 millimeter wide abdomen and four millimeters to the head.
The abdomen of the larvae is light gray-brown and has a light stripe along the back on segments six to ten. Apart from that, the larva has no special drawings. On the sides of the eighth segment, as on the ninth segment, there are rounded spines. On these segments and also on the seventh segment, small hairs grow that increase in length towards the back. The epiproct is longer than it is wide, and is almost the same length as segments nine and ten combined. While the Paraproct is barely as big as the Epiproct, the abdominal appendages only reach 80% of the length.
The top of the prothorax is covered by a dark patch; the synthorax is light brown. The wing sheaths reach the sixth abdomen segment. The thighs of the rear pair of legs reach 3.5 millimeters and the corresponding rails 4.3 millimeters. There are also three somewhat darker rings on the thighs of the middle pair of legs.
At its widest point, the head with its pronounced eyes is almost as wide as the abdomen. Its rear edge is concave and the entire back of the head is covered with small spines. The antennas are made up of seven segments and are covered with short hairs. The third segment is the longest, followed by the seventh, sixth, fifth, fourth, second and first segments in descending order. The lower lip is triangular and extends in its rear part to the base of the second pair of legs. There are also eleven bristles on both sides, the middle four of which are the shortest.
Similar species
The species Erythrodiplax fusca , Erythrodiplax abjecta and Erythrodiplax ines are very similar to Erythrodiplax melanorubra . While the females cannot always be differentiated with certainty, the males can always be differentiated based on the penis structure. To distinguish it from Erythrodiplax fusca , the shape of the spot in the rear pair of wings can also be used. In colored individuals, Erythrodiplax melanorubra and Erythrodiplax abjecta differ in color.
credentials
- ↑ a b c d e Donald Joyce Borror - A Revision of the Libelluline Genus Erythrodiplax (Odonata) p. 184ff , The Ohio State University, Columbus, 1942.
- ↑ a b c d e Jorge Limongi : Estudio morfo-taxonómico de nayades de algunas especies de Odonata (Insecta) en Venezuela (II) . (pdf) In: Memorias de la Sociedad de ciencias naturales "La Salle" . 131-134, 1991, pp. 405-420. ISSN 0037-8518 .
- ^ Charles W. Heckman: Encyclopedia of South American Aquatic Insects: Odonata? Anisoptera . Springer Netherlands, 2006, ISBN 978-1-4020-4802-9 , pp. 264 .