Indian royal dragonfly

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Indian royal dragonfly
Indian dragonfly (Anax immaculifrons), male

Indian dragonfly ( Anax immaculifrons ), male

Systematics
Order : Dragonflies (Odonata)
Subordination : Dragonflies (Anisoptera)
Superfamily : Aeshnoidea
Family : Noble dragonflies (Aeshnidae)
Genre : Royal Dragonflies ( Anax )
Type : Indian royal dragonfly
Scientific name
Anax immaculifrons
Rambur , 1842

The Indian Emperor Dragonfly ( Anax immaculifrons ) is a dragonfly from the family of aeshnidae (Aeshnidae) and the largest in Europe occurring dragonfly, although the range of the mainly in southern and parts of East Asia encountered kind in continental Europe only to small areas of Southeast Europe , together with the Balkan Peninsula is restricted. Another special feature of the Indian royal dragonfly is the guarding of the male of a previously mated female, which is unusual for dragonflies.

features

Males of the Great Royal Dragonfly ( A. imperator ), belonging to the same genus, with clearly different color patterns.

The Indian royal dragonfly has a wingspan of 120 and a body length of 86 millimeters. As with many dragonflies, the sexes of this species also differ in terms of their color patterns and differ greatly from those of other species of the royal dragonflies ( Anax ). In East Asia there are specimens of the color scheme described here as well as those with a reddish color. It has not yet been clarified whether this is a color variant or a subspecies.

male

A closer shot of a male

The male has a dirty or pale ocher-colored labium (lower lip) and a green-yellow labrum (upper lip) with a few black-brown areas. The face is pale blue-green, bordered by a narrow black border. The eyes appear sapphire blue in the living animal, also framed in a black border.

The male's prothorax (the anterior segment of the thorax or chest area) is dark red-brown and appears paler on the sides, and the rear lobe has a thick hem of long hair. The thorax has a pale and blue-green basic color on the dorsal side and the central keels on this side an additional black-brown basic color. The lateral side of the thorax is turquoise blue and has another black and narrow stripe on the shoulder side and another over the posterolateral side that tapers towards the top. The metepimeron (rearmost part of the thorax) is closed with another line in the same color and shape as the previously mentioned ones. The legs are colored black. The wings appear glassy and are discoid (disc-shaped) and extensively tinted amber, whereby this color becomes darker and darker near the wing base. The pterostigma (wing mark typical of dragonflies) varies between ocher and red-brown and takes up about three membranes.

The first segment of the male's abdomen is completely black. The second is turquoise blue and has black structures and a central dorsal and transversal drawing that is reminiscent of a seagull in flight and a fine central dorsal line with an apical, square and black spot. The flanks of the third segment are also colored turquoise blue. Apically, this segment is also black and has a black twin spot with fine structures on the middle dorsal side. Segments four to eight are partially black on the apex, whereby the color changes towards the base of the segment to a pale red-brown and finally turns into a pale blue. The ninth segment has a reddish brown lateral and black dorsal side, whereby this shade decreases further upwards. The tenth segment is colored black or red-brown on the back, with the rest of the segment being colored black in both variants. The cerci (abdominal appendages) of the male are evenly shaped and have a paler red-brown or ocher basic color. The roots are narrow and triangular, with a notched vertex and one or two small spines on each side.

female

female

The appearance of the female is similar to that of the male, but here the turquoise-blue color components on the thorax and abdomen of the male are replaced by pale green. The black markings in the male are additionally provided with red-brown thighs at the tips of the female. In addition, the first abdominal segment of the female is completely red-brown in color. The dorsal side of the thorax in the female is pale brown instead of blue-green. The color of the wings, which is stronger in the male, is weak or not at all pronounced in the female. The female's cerci are shorter and saber-shaped. They are also colored black-brown here.

larva

The larva of the Indian royal dragonfly is similar to that of the small and large royal dragonfly, but its head can appear much more massive with a width of 11 millimeters and the forehead stands out much more than in the larval forms of the sister species. The basic color of the larva is pale brown and has several darker markings. In the last stage it reaches a body length of 49 to 57 millimeters. The labium appears comparatively long and becomes significantly narrower towards the rear from the pre-mentum (the final part of the labium). The distal and concave edge of the palpus (feeler) has an angled outer corner and a long inner tooth. The distal edge of the prementum has a deeply excavated notch that is flanked by a pair of rounded lobes. The base of the hips of the first pair of legs has an oblique angle between the large posterior lobe and the slender anterior lobe. The legs are long and have protruding stripes on the distal side of the femura. The abdomen has some drawing elements typical of the larvae of noble dragonflies, ranging from the second to the eighth abdomen segment. There are also scar-like markings laterally on the surface from the third to the ninth segment and several point-like spots on the third to the seventh segment. The dorsal side of the abdomen is covered with fine hairs that sprout from larger, cavity-like and scale-like attachment points. Segments six to nine also have some spines on the lateral side, which are also missing in the larvae of the other species. The length of the cerci almost corresponds to that of the eight to ten segments combined. The epiproct (unpaired posterior plate of the eleventh abdominal segment) is strongly keeled, has a basal surface covered with hair and a deeply etched distal edge.

Occurrence

The Indian royal dragonfly can often be found on the waters of the Nilgiri Mountains in India .

The Indian royal dragonfly inhabits Europe , South Asia and China . In Asia, the species lives particularly in the areas south of the Indian city ​​of Mumbai , including the Nilgiri Mountains or the mountains of Sri Lanka . The species is also common in the eastern ghats . It becomes rarer north of Mumbai. In the Himalayas e.g. B. it rarely appears.

Potamia brook near Kalloni on Lesbos in the Aegean Sea

In Europe, the Indian royal dragonfly inhabits the coast of the Aegean Sea , the south of Turkey , Cyprus and the mainland of Greece with some islands, including those of the Dodecanese and next to them, Ikaria , Lesbos and Rhodes . Along with the large dragonfly ( A. imperator ), the small royal dragonfly ( A. parthenope ) and the red dragonfly ( A. ephippiger ), it is one of the four species of the royal dragonfly genus that occurs in Europe.

The habitat of the species is consistent with that of other species in the genus. Like the Indian royal dragonfly, it inhabits a wide range of stagnant waters. In addition, it also inhabits mountain rivers and especially streams. It can be found up to a height of 2,286 meters. The population density is mostly low due to the territorial formation of the males.

threat

The Indian royal dragonfly can be found in many places, especially in the Asian part of its range. The global population is classified by the IUCN as "not endangered". In the European Red List, however, the species is listed as "vulnerable" (VU / vulnerable).

Way of life

Male in flight

Like other noble dragonflies, the Indian dragonfly is a persistent flyer that prey on any insect in flight . Prey animals are especially different two-winged animals . Similarly, butterflies of the genera Catopsilia and Eurema or other small precipitates than the Indian Königslibelle dragonfly, as the traveling Dragonfly ( Pantala flavescens ) or Trithemis aurora from the kind of sun pointer frequently captured. As with many other noble dragonflies, the males of the Indian royal dragonfly also form territories from which other males are driven away. The Indian royal dragonflies approach particularly partially or completely shaded waters.

Reproduction

Mating wheel

The flight time of the Indian royal dragonfly in Europe is between May and September. As with other dragonflies, the pairing takes place in the form of a pairing wheel . The egg-laying takes place together with a guard on the part of the male, which is unusual for dragonflies. Unlike other dragonflies, this does not accompany the female by grasping it with its cerci behind the head and adopting the tandem position typical of dragonflies . Instead, it remains in the immediate vicinity of a previously mated female while it is laying eggs and has no direct body contact with it, and guards it by driving away other males entering the territory and thus preventing other males from fertilizing. The female often lays her eggs under water on reed-like plants in flowing waters. The larvae, which occasionally appear in large numbers, probably need two years to develop into an imago . As with other dragonflies, the larvae of this species also feed predatory and have also been spotted preying on smaller frogs . According to sightings, these are supposed to be specimens of the Iberian water frog ( Pelophylax perezi ), which is unlikely due to the different distribution areas of the two species.

Systematics

The Indian royal dragonfly was first described by Jules Pierre Rambur in 1842 and has not seen any name changes or conversions since then. The prepared type specimen is now in the Museum of Natural Sciences in Brussels .

gallery

  • Top view of a male

  • Frontal view of a male

  • Lateral view of a male

  • Rear view of a flying male

  • Distant view of the same specimen

  • Flying male in the vegetation

Individual evidence

  1. ↑ a b c d e f g h Anax immaculifrons (Rambur, 1842) at LibellenWissen.de, accessed on December 22, 2019
  2. ↑ a b c d e f g h i j k l m F. C. Fraser: The Fauna of British India, including Ceylon and Burma, Odonata Vol. III , Red Lion Court, Fleet Street, London: Taylor and Francis, 3rd edition, P. 156/57, 1936.
  3. ^ A b S. G. Butler: The larvae of the European Aeshnidae (Anisoptera) , Odonatologica 27, 1st edition, pp. 1/23, 1998.
  4. ↑ a b B. Singhand, S. Kumar Jain: Interspecific Relation in Anax Immaculifrons with Frog , Department of Zoology, Agra College Agra, 1st edition, pp. 72/74, 2013, accessed December 27, 2019.
  5. ↑ Anax immaculifrons (Rambur, 1842) at the IUCN , accessed on December 22, 2019.
  6. ^ TN Ananthakrishnan, KG Sivaramakrishnan: Dynamics Of Insect Behavior , Scientific Publishers, 1st edition, p. 163, 2012, ISBN 9789386347534 .
  7. ^ A. Martens, A. Günter, F. Suhling: Diversity in mate-guarding types within the genus Anax (Odonata: Aeshnidae) , Scientific Publishers, 1st edition, p. 163, 2012, accessed on December 27, 2019.
  8. ↑ KD Dijkstra, V. Kalkman: Early spring records of dragonflies from southern Turkey, with special reference to the sympatric occurrence of Crocothemis erythraea (Brullé, 1832) and C. servilia (Drury, 1773) (Anisoptera: Libellulidae). Notulae odonatologica 5 (7): pp. 85/88, 2001, accessed December 29, 2019.
  9. ↑ Anax immaculifrons (Rambur, 1842) from Fauna Europaea, accessed on December 27, 2019.

literature

Web links

Commons : Indian Royal Dragonfly  - Collection of images, videos and audio files