Anisoptera

Schneider, Thomas, Ikemeyer, Dietmar, Müller, Ole & Dumont, Henri J., 2018, Checklist of the dragonflies (Odonata) of Iran with new records and notes on distribution and taxonomy, Zootaxa 4394 (1), pp. 1-40 : 27-36

Anisoptera

Four species of Aeshna are known from Iran. Aeshna vercanica ( Fig. 17 ) was described only recently (Schneider et al. 2015). It is restricted to the Hyrcanian forest of the Caspian Sea region in Iran and Azerbaijan. Strong populations of A. isoceles are found along the Caspian Sea and in W-Iran at Lake Zarivan (Zarivar = Zerivar = Zeribar). Aeshna isoceles antehumeralis (Schmidt 1950) , is not found at the Caspian Sea as already noticed by Schmidt (1954) and is present only in a minority of specimens from Lake Zarivan. The subspecies level of A. isoceles antehumeralis is not followed by modern taxonomy and is now generally considered as a colour variant and not a valid subspecies, although any reference evidences is missing in those publications like Kalkman et al. (2015).

Four Anax species occur in Iran. Anax imperator and A. parthenope are widespread and occur in the whole country, whereas A. immaculifrons is scarce ( Fig. 18 ). Anax ephippiger is widespread in Iran, sometimes forming swarms which follow those of Pantala flavescens (Ikemeyer et al. 2015) .

Brachytron pratense has been reported from the Caspian Sea region and the northwest of Iran . We did not see the species in Iran, probably due to its early flight period (April).

Caliaeschna microstigma is found along brooks and smaller rivers in the mountains of N- and W-Iran reaching the Fãrs province in the south. It remains absent from the SE.

The family Gomphidae comprises ten species in Iran. Anormogomphus kiritshenkoi is said to occur in Iran, but precise data are missing. The old records by Fraser (1934) are vague, mentioning just the Makran Coast and the Persian Gulf (cf. Schmidt 1954, c.f. Heidari & Dumont 2002). More recent records from rice fields in Mazandarãn province ( Ghahari et al. 2009) are doubtful and rejected. However, the locations around Basra (Zobeir) in Iraq ( Morton 1919, 1920) are well documented and close to the Iranian border. The reports from Alwand River in east Iraq ( Sage 1960) are also only few kilometres away from the Iranian border. Thus, this species should also occur in SW Iran.

As discussed previously the record of Stylurus ubadschii available for Iran is not clear ( Schneider et al. 2017a). Most of the specimens mentioned by Martin (1912) as G. davidi more probably belonged to G. kinzelbachii (for details see Schneider et al. 2017a). In the report from Martin (1912) a female of S. flavipes is mentioned, but this was not further characterised later by Schmidt (1954). However, a male and a female not mentioned by Martin (1912) are introduced 43 years later: The male was from April 1907 and should have been present, when Martin was working on the material. Furthermore, a young female is mentioned by Schmidt (1954) captured in 1920 and attributed by Martin to G. simillimus (interestingly such an attribution was also made in the case of the typus collected by Sage, later described as G. kinzelbachi by W. Schneider). This female was labelled Perse/Java deleted. Thus, it remains unclear from where it came. Schmidt wrote the female belongs to the male and gives several details, which are not sufficient to identify this female. Furthermore, he wrote the male was checked by Asahina, who wrote back, that the male is quite similar to a male from Misis in Turkey ( Schmidt, 1954). Asahina further stated that there were further four males and three females, all without abdomen. The question remains, which individual from which location was the basis of Asahina`s drawing shown in the report of Schmidt (1954). Thus doubts came up, if the figure is really based on a Persian specimen as indicated or on a specimen from Misis in Turkey. Moreover, also the possibility exists that the specimen’s label was confused, and therefore not mentioned by Martin (1912). Whatever, may be the truth, we are unable to clearly confirm if S. ubadschii was captured in Persia in 1907. However, over 100 years there were no further records of this species until in May 2017 Elias Schneider and one of the authors (TS) detected six males of S. ubadschii at the Zoreh River near the influx into the Persian Gulf ( Fig. 19). Thus, the record documented here may be the first real proof that S. ubadschii is present in Iran.

Gomphus schneiderii occurs in different colour variations in Iran. Typical dark forms inhabit the northern slopes of the Alborz Mountains. The typical yellow basal central spots on the dorsal abdomen on S8-S9 are sometimes absent in individuals from the Caspian Sea region. South of the Alborz more yellow forms can be found ( Fig. 20 , left). Yellow forms found in neighbouring countries have sometimes been attributed to separate species as G. amseli Schmidt (1961) (in Afghanistan) or as G. schneiderii transcaspicus Seidenbusch (1997) (in Turkmenistan). Only small and subjective structural differences have been found between these taxa and G. vulgatissimus ( Morton 1915, Seidenbusch 1997a, 1997b). Therefore, further barcoding investigations are needed to clarify the taxonomy of these four closely related taxa. Gomphus kinzelbachi is not rare in Iran and can be found on several river systems in SW Iran ( Fig. 20 , right) ( Schneider et al. 2017a, 2017b). Lindenia tetraphylla is found mainly in S-Iran. Local specimens are strikingly pale.

Onychogomphus is represented by four species. Onychogomphus forcipatus albotibialis is widespread in NW- and N-Iran, the southern parts of the Zagros Mountains and eastern Iran ( Fig. 21 ). At the range boundary very small, pale to grey individuals with reduced black abdominal and thoracic markings occur. These can easily be confounded with the co-occurring Onychogomphus lefebvrii . However, in the latter the lower appendices are without any knobs. Pale forms of O. forcipatus albotibialis were named ssp. lucidostriatus ( Schmidt 1954) . However, they are not separated geographically, don't show any structural differences in their appendages and may occur in the same locations as typical O. f. albotibialis in S-Iran. Therefore we suggest to drop this subspecies as expected and suggested previously by Boudot et al. (1990). Especially, in the overlapping regions of O. forcipatus albotibialis and O. lefebvrii both species are small and pale. O. lefebvrii is found mainly from W- to SW- and S- Iran, as well as in E-Iran. In the SE the species reaches the Hormozgãn province, but it is absent from E- Hormozgãn and Sistãn-va-Baluchestãn ( Fig. 21 )

Onychogomphus flexuosus is more common on big lowland rivers in SW-Iran ( Fig. 22 ). Specimens from S- Iran are usually tinier and paler than those from Georgia or Turkey. Onychogomphus assimilis occurs along rapid flowing mountain rivers in the Zagros and Alborz Mountains ( Fig. 22 ).

Paragomphus lineatus is not rare along sparsely vegetated rivers in S-Iran ( Fig. 22 ). The colour and size of the species is highly variable. Specimens from the province Ilãm are usually larger, more robust and often without dark markings on the abdomen. Specimens from the provinces Sistãn-va-Baluchestãn, and Hormozgãn, are tinier and have a more vivid colouration with well-defined black markings on the abdomen.

At least three Cordulegaster taxa are found in Iran. Cordulegaster vanbrinkae is very dark and the darkest member of the boltonii -group. However, yellow-marked individuals occur in the Golestãn province. This species occurs in the Hyrcanian forest on the northern slopes of the Alborz Mountains in the south Caspian Sea region. Cordulegaster nobilis are impressive insects with very large and yellow individuals found mainly in the Zagros Mountains. Cordulegaster coronata ( Fig. 23 , left) is smaller and occurs in the NE, near the Afghan border ( Schneider & Ikemeyer 2017). On the basis of exuviae we previously assigned the population from Azaneh to C. i. nobilis ( Seidenbusch et al. 2015, Ikemeyer et al. 2015). However, already in this description we noticed that the exuviae were very near if not identical to Cordulegaster coronata from Middle Asia ( Seidenbusch et al. 2015). To clarify this we went again to this location one year later in June, when we detected the imagines. The adults fit phenotypically very well to the original description by Morton (1915 –1916). Meanwhile molecular data revealed that they are identical with middle Asian Cordulegaster coronata (manuscript in preparation).

S. flavomaculata is the only member of the family Corduliidae in Iran ( Fig. 23 , right) as the record of Cordulia aenea in the NW by Rastegar et al. (2013) is regarded as unreliable (see above). As Schmidt (1954) mentioned, the species from Iran’s Caspian Sea region are larger than those of any other region. The measurements of our specimens from the Caspian Sea revealed: males (n = 4): total length: 5.3–5.9 cm, abdominal length: 4.3–4.4 cm, hindwing length: 3.9–4.1 cm; females (n = 3) total length: 5.9–6.1 cm, abdominal length: 4.5–4.7 cm, hindwing length: 4.4–4.6 cm). The measurements given for European specimens (not differentiated between males and females) given by Wildermuth (2008) are clearly smaller (total length: 4.5–5.4 cm, abdominal length: 3.3–4.3 cm, hindwing length: 3.2–3.9 cm).

Libellula depressa is widespread and frequent and occurs also at high altitudes (up to 2300 m). Libellula quadrimaculata and L. pontica are rare ( Fig. 24 ). Strong populations of the latter exist along the Aras River in NW- Iran. Libellula quadrimaculata was found on the remnants of Lake Arzhan and at Lake Zarivan.

Two members of Brachythemis are found in Iran ( Fig. 25 ). Brachytehmis fuscopalliata is present at large lowland rivers in SW-Iran. Brachythemis contaminata has its western distribution limit in SE-Iran.

With 11 taxa, Orthetrum is the most speciose genus in Iran. Orthetrum ransonnetii and O. luzonicum occur in E-Iran. Our records for the latter are the second for Iran. The reports of O. luzonicum from Mazandarãn ( Ghahari et al. 2009) are definitively wrong as these locations are completely out of its known range. Interesting is the occurrence of O. a. albistylum and the subspecies O. a. speciosum in Iran ( Figs. 26 , 27 ). The latter is found only in the Caspian Sea region, whereas the nominate form is present in NW- and W-Iran. The taxonomic status of the subspecies O. a. speciosum is not clear. However, our specimens from the Caspian Sea fit well with the pictures shown in the Dragonflies of the Japanese Archipelago ( Okudaira et al. 2001). Until now it is unclear how far west this eastern Palaearctic taxa occurs, however, it is meanwhile found abundant in south-eastern Russia ( Malikova 1997, Yakubovich 2010, 2013). Thus, the Caspian Sea region may harbour its western most outposts. Further molecular work including material from the Far East is needed to clarify the taxonomic value of this subspecies, which is mainly a larger form of the nominate species.

Sympetrum is present with eight species in Iran. Sympetrum haritonovi and S. vulgatum decoloratum are restricted to high altitude ( Schneider & Ikemeyer 2017). Sympetrum arenicolor is common along brooks between 800 and 1700 m in NE-Iran, and S. meridionale frequents the same habitats between 200 m and 1900 m in NW- and W-Iran ( Figs. 28 , 29 ). Sympetrum flaveolum is generally easy to identify by its saffron wings. However, specimens from Neor Lake in the Talysh Mountains and specimens from the Armenian Highlands had yellow in the wing base reduced to sometimes completely absent. These specimens fit the description of the S. f. austrinum Akramowski, 1948 from Armenia, and are also found in Anatolia ( Dumont 1977).

Sympetrum sanguineum occurs mainly in N- and W-Iran. On the Armenian Highlands (above 2000 m) very small individuals were found, nearly the size of S. haritonovi . These individuals differ from those from lower altitudes and fit in some aspects S. s. armeniacum (Selys, 1884), a subspecies mentioned by Akramowski (1948) for Armenia above 1900 m. Such individuals are also present in Anatolia ( Dumont 1977). Specimens from the Armenian Highland in Iran had little to no amber in the wing base and the veins of the wings were reddish, reminiscent of a Trithemis . The pterostigma of these individuals is smaller, less dark and more reddish than in typical S. sanguineum ( Fig. 30 ).

Crocothemis erythraea and C. servilia are both present in Iran ( Fig. 31 ). Curiously enough, C. erythraea females with blue to grey pruinose thorax and abdomen and yellow markings on the side of the abdomen reminiscent of a small Libellula depressa male can be found in NW-Iran near the Aras River.

Pantala flavescens is widespread and often seen in big swarms (Ikemeyer et al. 2015). Diplacodes lefebvrii is present in the whole country but more frequent in the South. Selysiothemis nigra is widespread, and can be observed at high temperatures (> 55°C), sometimes in high density (n> 1000), for example on the river Karkeh in SW Iran.

The Trithemis genus is present with six members. Trithemis annulata is widespread and one of the most frequent Trithemis . Trithemis arteriosa is rare, found predominantly in Hormozgãn province. T. aurora is found in SE-Iran, and has its western range limit in Iran. The record of T. aurora from Kuzestan ( Bakhshi & Sadeghi 2014, and old Museum record see above) may have involved vagrants and the species seems to be autochthonous in Iran only or mostly in Sistãn-va-Baluchestãn. Trithemis pallidinervis was reported only recently from Iran (Schneider et al. 2016). Its western range limit seems situated in the province Sistãn-va-Baluchestãn in SE-Iran although migrants or vagrants were found in the past in the South of the Arabian Peninsula ( Schneider & Dumont 1997).

Zygonyx torridus is rare, and breeding sites are yet to be discovered. Recent observations are from rivers in the Khabr National Park on locations above 1700 m ( Ebrahimi et al. 2014). In this region winters are cold with temperatures well below 0°C. Such rivers are unlikely to be the breeding sites of the observed individuals, which would be better regarded as vagrant individuals coming from the foothills.

Figures

FIGURE 17. Male of Aeshna vercanica, shaded mountain rivulet with cascades near Loveh village, Golestãn province, 37.34420°N, 55.66417°E, 598 m, 20.VII.2014. Photo DI.

FIGURE 18. Distribution of Anax imperator (dots), A. parthenope (triangles), and A. immaculifrons (squares) in Iran.Closed symbols: records from 2010 onwards, open symbols:records before 2010.

FIGURE 20. Males of left: Gomphus schneiderii (Azarbãyejãn-e-Garbi, location 136) and right: Gomphus kinzelbachi (Khuzestãn, location 34). Photos DI.

FIGURE 23. Males of left: Cordulegaster coronata (34.95685°N 60.16719°E, Khorãsãn-Razavi, 1683 m, 09.VI.2016) and right: Somatochlora flavomaculata (Gilãn, location 83). Photos DI.

FIGURE 24. Distribution of Libellula quadrimaculata (dots) and L. pontica (triangles) in Iran. Closed symbols: records from 2010 onwards, open symbols: records before 2010.

FIGURE 26. Distribution of Orthetrum a. albistylum (dots) and O. a. speciosum (triangles) in Iran. Closed symbols: records from 2010 onwards, open symbols: records before 2010.

FIGURE 27. Orthetrum a. albistylum and O. a. speciosum. Note the strong difference in size between a female of O. a. speciosumfrom Iran (above), and a female of the nominate form from Central Europe (below).

FIGURE 29. Males of left: Sympetrum arenicolor (37.19852°N, 57.41659°E, Khorãsãn-e-Razavi, 1419 m, 23.VII.2014) and right: Sympetrum meridionale (38.38966°N 47.55723°E, Ardabil, 1106 m, 10.VIII.2016). Photos DI.

FIGURE 30. Sympetrum sanguineum in Iran: Comparison of a typical male from the Caspian Sea region (right) and a smaller variation with reddish wing veins and pterostigma which is sometimes treated as S. s. armeniacum from the Armenian Highland (left) in NW-Iran.

FIGURE 31. Distribution of Crocothemis erythraea (dots) and C. servilia (triangles) in Iran. Closed symbols: records from 2010 onwards, all records by TS and DI.

FIGURE21.Distribution of Onychogomphusforcipatus albotibialis (dots) and O. lefebvrii (triangles) inIran.Closed symbols: records from 2010 onwards, open symbols: recordsbefore 2010.

FIGURE22. Distribution of Onychogomphus flexuosus (triangles), O.assimilis (dots), and Paragomphus lineatus (squares) in Iran.Closed symbols: recordsfrom 2010 onwards, open symbols: records before 2010.

FIGURE25. Distribution of Brachythemis fuscopalliata (triangles)and B. contaminata(dots) in Iran.Closed symbols:records from 2010 onwards, open symbols: records before 2010.

FIGURE28. Distribution of Sympetrum meridionale (triangles) and S. arenicolor (dots) in Iran.Closed symbols:records from 2010 onwards, open symbols: records before 2010.