Ringed Cascader, Zygonyx torridus, Kringklatertjie
Ringed Cascader, Zygonyx torridus is large sized, black with yellow ringed abdomen.
Family Libellulidae (Leach, 1815)
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Key identification features:
- Face yellow brown to dark brown in front, blackish metallic above. Labrum and anteclypeus dark brown. Postclypeus dark brown, dull yellow at sides. Frons yellow brown to dark brown along Covered with dark hair. margin and at sides, sightly dimpled black metallic purple in front and above. Top of head shiny dark brown, slightly metallic
- Eyes blackish brown
- Thorax slightly metallic black, with some indistinct (with age) broken yellow stripes Hind legs (largely) black. Neck and dorsal thorax (lateral thorax with less) covered with white hair. white hair
- Wings clear and pointed, becoming slightly smoky with age. Pterostigmas, long and black, can be variable in length, sometimes longer in fore wing, 4.0–4.8 mm, compared to 4.2–4.5 mm in hind wing. 9½-11½ Ax in fore wing
- Abdomen black with yellow side patches and fine yellow lines on top of each segment. Segments 4-8 with large lateral pale spots . Yellow patches almost connected on s6 - 7, faint on s9, in the field giving the appearance that the abdomen is ringed in black and yellow . Segment 10 and appendages black
- Similar to male, with black and yellow stripes on thorax distinct and top of head dull brown. Abdomen S1 - 2 broad yellow bands
- Streams and rivers and shallow rivers with bush-lined or open banks, open landscapes, but sometimes in open areas in forest or shaded by gallery forest. Often faster sections (rapids, falls) with rocks and a gravelly and/or sandy bottom.
- From 0 to 2300 m above sea level, but mostly below 1500, although possibly even higher up.
- It hawks up and down over riffles and glides, hovering over open stretches of fast water, or flies rapidly and high over and between bushes and trees away from the water, both in the day and at dusk.
- The female is rarely close to the water and usually found hawking among bushes and trees.
Compared with other species:
- Metallic tip of frons and vertex distinguishes Z. natalensis (Blue Cascader) and Z. torridus (Ringed Cascader) from Orthetrum (Skimmers).
- Both Z. natalensis and Z. torridus hunting behaviour of flying rapidly over splash zones are similar, but is unlike any Orthetrum (Skimmer)
- Z. natalensis is similar to but smaller than Z. torridus. Z. torridus is blackish brown with distinct yellow marks on abdomen and lightly pruinescent
- Female Z. natalensis yellow markings make up only a small fraction of the abdominal segments (whereas it is about 50% Z. torridus ),
Z. natalensis vertex is highly metallic . All brown and only slightly metallic in Z. torridus . The upper corners of Z. natalensis frons are metallic , but yellow in Z. torridus ).
- Common in the southern , eastern and northern provinces but not in the dry central region
- Angola; Benin; Botswana; Burkina Faso; Côte d'Ivoire; Cameroon; Cape Verde; Central African Republic; Democratic Republic of the Congo; Ethiopia; Gabon; Gambia; Ghana; Guinee-Bissau; Kenya; Liberia; Malawi; Mali; Morocco; Mozambique; Namibia; Nigeria; Republic of South Africa; Rwanda; Sierra Leone; Socotra (Yemen); Sudan; Tanzania; Togo; Tunisia; Uganda; Zambia; Zimbabwe