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Aeshna mixta Latreille Migrant hawker Description A. mixta is a medium-size hawker dragonfly, similar in pattern and coloration Habitat to A. cyanea, A. juncea, and Brachytron pratense. In males, the antehumeral stripes are much reduced or absent, thus separating A. mixta from the other three species. The costa is dark brown, distinguishing it from A. juncea in which it is bright yellow. The abdominal spots on the dorsal surface of segments 9 and 10 are paired, not joined together to form two broad bands as in A. cyanea. A. mixta is much smaller than both A. juncea and A. cyanea, though it is of similar size to B. pratense. However, A. mixta lacks the very hairy thorax of that species, and its pterostigmata are not as elongated, neither do their flying seasons overlap. In female A. mixta, the body markings are similar to those of the male, but the coloration is much duller and the abdominal spots are a pale yellowish green. The anal appendages of the female are the longest of all our resident aeshnids, excluding B. pratense, being more than the combined length of abdominal segments 9 and 10. A. mixta breeds in ponds and lakes, including flooded sand and gravel pits, with well-vegetated margins. It also breeds in canals, ditches, which in coastal areas may be quite brackish, and, occasionally, sluggish rivers and streams. On heathlands, A. mixta appears to avoid the more acidic waters tolerated by A. juncea. Breeding biology A. mixta is usually only weakly territorial and occurs at higher densities than larger aeshnids. It is not uncommon to see three or four males flying together in a confined area without aggression. Even more than other Aeshna species, A. mixta is frequently seen hawking at the edges of woods, along woodland rides and glades, and beside tall hedges away from water, sometimes in large numbers. Copulation time is lengthy and usually takes place in marginal vegetation near the water's edge. Females insert their eggs into the tissues of emergent plants, such as bulrush, often above water level, and will occasionally oviposit into bare mud. Diapause is spent in the egg stage. Larval development is rapid, being completed in one season. Flight periods A. mixta has a late flying season, from late July to late October. It can be seen Status and distribution European and world distribution with many other late summer species, such as A. cyanea, A. grandis, Sympetrum striolatum and the commoner damselflies. A. mixta has not yet been recorded from Ireland. In Britain it breeds from Cornwall and south Wales to the Humber, but is most common in southeastern and midland counties. It has clearly extended its range in Britain during this century Lucas (1900) wrote, 'This dragonfly seems to be almost confined to the south-eastern corner of England and the Channel Islands, and even from there but few captures have been recorded'. Longfield (1949c) 'reported that A. mixta was most commonly found in southern and eastern ' counties below the Severn/Wash line, and cites a few instances of its being found further north. Benton (1988) records the spread of A. mixta into Essex in :the 1930s and 1940s. In Bedfordshire, it was described in 1947 as being by no means common, but it is now ubiquitous (Dawson 1988). Holland (1983) records the spread of this species in Gloucestershire since the 1970s, as does Allport (1985) in Yorkshire. In Cornwall, breeding was confirmed for the first time in 1991. It was first recorded in Cheshire in 1993. The population of A. mixta is sometimes increased greatly in late summer by influxes from the continent. On 17 August 1982, in excess of a thousand were seen by K D Wilson in a wood near Brighton, Sussex, many of which were teneral. Three days later he found a similar number in a wood near Eastbourne, up to 25 settled on a single branch. A. mixta is common throughout most of south and central Europe, being found as far north as Denmark. It occurs in North Africa, the Caucasus, and east to China and Japan. 68
Montiaghs Moss, near Aghalee, Co Antrim. June 1991 Altitude 15 m. Cut-over bog in Lough Neagh basin, with many small sedge-filled pools formed from peat cuttings, containing broadleaved pondweed. Adjacent willow, alder and birch scrub in heathland dominated by purple moor-grass. Site for Coenagrion lunulatum, C. pulchellum, Brachytron pratense, Aeshna juncea and Sympetrum danae. PHOTOGRAPH: R THOMPSON Silver Flow NNR, Kirkcudbrightshire (Galloway) June 1986 Altitude 260 m. Series of shallow pools and channels, with emergent bogbean and marginal and submerged Sphagnum species, in an area of blanket bog containing deergrass, common cottongrass, purple moor-grass, heather and hummocks of Sphagnum. Site for Aeshna caerulea, A. juncea, Libellula quadrimaculata, Pyrrhosoma nymphula and Enallagma cyathigerum. PHOTOGRAPH: D J CLARKE Lough Gealain near Mullagh More, The Burren, Co Clare. May 1989 Altitude c. 60 m. Turlough (see Glossary) in area of limestone pavement, with mostly bare shoreline and some stands of marginal common reed and rushes, with hazel scrub nearby Lake bed covered by deposit of marl. Site for Orthetrum cancellaturm Brachytron pratenso and Coenagnon pulchellum PHOTOGRAPH: R THOMPSON Loch Bran, Glen Mor, Inverness-shire July 1991 Altitude 195 m. Shallow peaty mesotrophic lake with sheltered bays, adjacent to birch and Scots pine woodland. <strong>Open</strong> water contains white waterlily, with emergent common reed and beds ot slender sedge and bottle sedge. Lake margin also has Sphagnum lawns with bog-myrtle and heather. Site for Somatochlora Libellula quadrimaculata, Sympetrum danae, S. striolatum and Lestes sponsa. PHOTOGRAPH: R THOMPSON
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Cover photograph: Aeshna juncea Ins
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@ NERC Copyright 1996 ISBN 0 11 701
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FOREWORD Having been on the fringe
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ACKNOWLEDGMENTS The following list
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Howard, G.; Howard, LW; Howe, M.; H
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Walker, D.S.; Walker, FA; WaLker, I
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CHECKLIST The following checklist i
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Aeshna mixta Latreille 1805 Aeschna
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THE BRITISH AND IRISH ODONATA IN A
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of distributions of dragonflies usi
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I 00 o o Figure 3. Map of coverage
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,o " Figure 5. Map of coverage at t
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FIELDWORK AND DATA MANAGEMENT METHO
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areas, and encouraged in this by bo
Page 32 and 33: Table 3. Distribution of each speci
Page 34 and 35: Table 4 (con°. Vice-county distrib
Page 36 and 37: Table 4 (cont). Vice-county distrib
Page 38 and 39: Computerisation and validation Havi
Page 40 and 41: dominance of one individual over an
Page 42 and 43: RESIDENT SPECIES Description Habita
Page 44 and 45: Calopteryx splendens (Harris) Bande
Page 46 and 47: Description Flight periods Status a
Page 48: Description Lestes dryas Kirby Scar
Page 51 and 52: Platycnemis pennipes (Pallas) White
Page 53 and 54: Pyrrhosoma nymphula (Sulzer) 1975-9
Page 55 and 56: Erythromma najas (Hansemann) 1975-9
Page 57 and 58: Coenagrion mercuriale (Charpentier)
Page 59 and 60: Coenagrion scituluni (Rambur) Daint
Page 61 and 62: Coenagrion hastulatuni (Charpentier
Page 63 and 64: Coenagrion lunulatum (Charpentier)
Page 65 and 66: Coenagrion armatum (Charpentier) No
Page 67 and 68: Coenagrion puella (Linnaeus) Azuxe
Page 69 and 70: Coenagrion pulchellum (Vander Linde
Page 71 and 72: Enallagma cyathigerurn (Charpentier
Page 73 and 74: Ischnura pumilio (Charpentier) Scar
Page 75 and 76: Ischnura elegans (Vander Linden) 19
Page 77 and 78: Ceriagrion tenellurn (Villers) 1975
Page 79 and 80: Aeshna caerulea (Strom) Azure hawke
Page 81: Aeshna juncea (Linnaeus) Common haw
Page 85 and 86: Sundon Springs chalk quarry, near L
Page 87 and 88: PLATE 1 Calopteryxvirgo adult PLATE
Page 89 and 90: PLATE 13 Libellula fulva adult PLAT
Page 91 and 92: Aeshna mixta Latreile Migrant hawke
Page 93 and 94: Aeshna cyanea (Muller) Southern haw
Page 95 and 96: Aeshna grandis (Linnaeus) Brown haw
Page 97 and 98: Aeshna isosceles (Muller) Norfolk h
Page 99 and 100: Anax imperator Leach Emperor dragon
Page 101 and 102: Brachytron pratense (Muller) Hairy
Page 103 and 104: Gomphus vulgatissimus (Linnaeus) 19
Page 105 and 106: Cordulegaster boltonii (Donovan) Go
Page 107 and 108: Cordulia aenea (Lin.naens) Downy em
Page 109 and 110: Somatochlora metallica (Vander Lind
Page 111 and 112: Somatochlora arctica (Zetterstedt)
Page 113 and 114: Oxygastra curtisii (Dale) Orange-sp
Page 115 and 116: Libellula quadrimaculata Linnaeus 1
Page 117 and 118: Libellula fulva Mailer Scarce chase
Page 119 and 120: Libellula depressa Linnaeus 1975-90
Page 121 and 122: Orthetrum cancellatum (Linnaeus) 19
Page 123 and 124: Orthetrum coerulescens (Fabricius)
Page 125 and 126: Sympetrum striolaturn (Charpentier)
Page 127 and 128: Sympetrum sanguineum (Muller) Ruddy
Page 129 and 130: Sympetruni danae (Sulzer) 1975-90 o
Page 131 and 132: Leuconhinia dubia (Vander Linden) W
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IMIVLIGRANTS AND ACCIDENTAL SPECIES
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POSSIBLE ADDITIONS TO THE BRITISH A
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SEASONAL OCCURRENCE PREVIOUS REPRES
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700 600 500 400 300. 200 100 0 90 8
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70 60 50 40 30 20 10 90 80 70 60 50
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Finally, differences in recorder be
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ODONATA LOCALITY 6411 V10E-COUNTY N
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Particularly in the case of residen
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conditions and which may be of grea
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1960s from its single locality alon
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pond. One of the authors did this o
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REFERENCES Aguilar, J. d', Dommange
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Gabb, R. & Kitching, D. 1992. The d
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Coenagrion rnercuriale (Charpentier
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Dee'. Transactions of the Natural H
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Circumboreal Occurring in a band en
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Marl A whitish clay soil with a hig
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Vulvar scale WATCH Weald Wheel posi
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Appendix 2. LIST OF PLANT NAMES Pla
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Libefiula depressa 5,6,14,17,18,19,
show all

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