Clues for sight identification of the small Orthetrum species in SW Turkey

Do you know the feeling of trying to identify a small Orthetrum species on sight? During a visit (20 May - 3 June 2000) to South-western Turkey it lasted a long time before we could tell them properly apart. In the region occur: O. coerulescens anceps, O. chrysostigma and O. taeneolatum. On this page the clues with which we could know the identity of the species with a binocular. Teneral males (row below) and adult males (second row).


Orthetrum coerulescens anceps	Orthetrum chrysostigma	Orthetrum taeneolatum

	*Orthetrum coerulescens anceps*	*Orthetrum chrysostigma*	*Orthetrum taeneolatum*
shape of the first segments of abdomen	segment two sometimes slightly inflated (swollen), segment three of same width as rest of abdomen	segment two inflated (swollen), abdomen contracted at segment three	segment two somewhat inflated (swollen), segment three of same width as rest of abdomen
base of hindwing	clear or with trace of yellow	always with small yellow spot	clear
size	medium sized: abdomen: 25-31 mm	medium sized: abdomen: 26-31 mm	small species: abdomen: 24-25 mm
colour of face	yellow or brown	yellow, brown or greenish*	may be bluish in adult males
colour of the eyes in old blue coloured males (added on behalf of Wolfgang Lopau)	eyes blue or blue-greenish	eyes blue or blue-greenish	eyes brown on the upper side
black line on the abdomen (in not pruinose animals) (added on behalf of Richard Seidenbusch)	fine line	very fine line	a distinctly broad line
max. number of creamy stripes on thorax and shoulder (not always good to see e.g. in pruinose individuals)	only one: on the shoulder	two: on the shoulder and one on the first half of side of the thorax	three: on the shoulder, and two on sides of the thorax
behaviour	never in obelisk posture	never in obelisk posture	during hot weather often obelisk posture
preferable sitting on .. (added on behalf of Wolfgang Lopau)	mostly sitting on plants, less so on the ground	generally on vegetation, sometimes on the ground*	always sitting on the ground
* Remark on the colour of the face of Orthetrum chrysostigma by Richard Seidenbusch: "I have seen not seldom greenish-faced ones (females) of this species" ** Remark on the sitting preference of Orthetrum chrysostigma by Richard Seidenbusch: " I had seen already Orth.chrysostigma mainly sitting on sandy-rocky bottoms (especially tenerals) in Israel (Lake Kineret) and Maroc (Immouzer)". red: most obvious characters purple: less obvious characters black: situation in other species
Does anyone has exceptions to the list of characters listed above? And does anyone have other suggestions for identification marks besides the ones mentioned?

	*Orthetrum coerulescens anceps*	*Orthetrum chrysostigma*	*Orthetrum taeneolatum*
Beside the size you can check in the hand detail of hamulus with the inner and outer branch male accessory genitalia under second segment

Literature Askew, R.R., 1988. The dragonflies of Europe. Harley Books, Essex UK. Schneider, Wolfgang, 1986. Systematic und Zoogeographie der odonata der Levante unter besonderer Berücksichtung der Zygoptera. Dissertation, Mainz. Jacquemin, Gilles & Jean-Pierre1999. Les Odonates (Libellules) du Maroc. S.F.O., France.