Megalagrion molokaiense
| Megalagrion molokaiense | ||||||||||||
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| Scientific name | ||||||||||||
| Megalagrion molokaiense | ||||||||||||
| ( Perkins , 1899) |
Megalagrion molokaiense is a possibly extinct dragonfly species from the family of the slender dragonflies(Coenagrionidae). It was endemic to the Hawaiian island of Molokaʻi .
features
Only males were collected from Megalagrion molokaiense . The known specimens have a body length of 53 to 57 mm and a wing span of 62 to 65 mm. The elongated body is reddish brown and black. The head is predominantly black on top. The eyes, face, mouthparts, and the horizontal stripes along the edge of the back are red. The thorax is broadly striped reddish-orange and black. The legs are reddish-orange. The upper side of the abdomen is mainly reddish with black markings on segments IV to VII. The segment tips VI and VII are almost completely black. The abdominal appendages of the males are short with the upper ones longer than the lower ones. The tips of the upper abdominal appendages are angular. Seen from above, the upper abdominal appendages have a broad internal flattened appendage with a small, sharp tooth protruding inward. The females and the larvae are undescribed.
Habitat and way of life
According to the first descriptor Robert Cyril Layton Perkins , the type specimens were collected in the Molokaʻi Mountains at an altitude of over 4,000 feet (1220 m). Nothing is known about the habitat and way of life of this species. In the similar species Megalagrion jugorum and Megalagrion nesiotes , the adult dragonflies do not seek out watercourses. It is believed that Megalagrion molokaiense lays its eggs in seepage water, on damp banks or in foliage. The adult dragonflies probably fly in forests and ridges with similar habitats as Megalagrion oahuense and Megalagrion nesiotes .
Systematics
Robert Cyril Layton Perkins described this form as Agrion molokaiense in 1899 . Clarence Hamilton Kennedy placed them in the genus Megalagrion in 1917 .
status
The IUCN lists Megalagrion molokaiense in the category “ critically endangered ” with the addition “possibly extinct”. The species has not been seen since the 1940s. Search expeditions in the known area of distribution were unsuccessful. The main threats come from ants and introduced ungulates.
literature
- Dan A. Polhemus: Damsels in distress: A review of the conservation status of Hawaiian Megalagrion damselflies (Odonata: Coenagrionidae). Aquatic Conservation: Marine and Freshwater Ecosystems Special Issue: Endangered Aquatic Habitats - A Symposium of the Entomological Society of America December 1992 3 (4), 1993: 343-349
- Dan A. Polhemus and Adam Asquith: Hawaiian Damselflies. A field identification guide. A Hawaii Biological Survey Handbook. Bishop Museum Press, Honolulu, 1996. ISBN 0-930897-91-9 . P. 67
Web links
- Megalagrion molokaiense inthe IUCN Red List of Threatened Species 2016.3. Posted by: Dan A. Polhemus, 2006. Retrieved May 5, 2017.
Individual evidence
- ^ A b c Dan A. Polhemus and Adam Asquith: Hawaiian Damselflies. A field identification guide. A Hawaii Biological Survey Handbook. Bishop Museum Press, Honolulu, 1996. ISBN 0-930897-91-9 . P. 67
- ^ RCL Perkins: Neuroptera. Fauna Hawaiiensis 2 (2), Cambridge University Press, 1899: 31-89
- ^ CH Kennedy: Notes on the penes of damselflies (Odonata). No. 2. The close relations inter se of the Hawaiian agrionines. Entomological News 28, 1917: 9-14. pls. 2–3, figs. 149.