گزارش جدید گیاه بیگانۀ(Onagraceae) Oenothera indecoraبرای فلور ایران

Nowadays, adventive invasive species are among the most significant threats to biodiversity. In recent years, numerous imported plants exhibiting invasive behavior have been reported along the Caspian coasts, particularly in Guilan province. During a field mission aimed at collecting plant specimens from the Hyrcanian forests in Guilan province, Oenothera indecora Cambess. from the Onagraceae family was collected and identified for the first time in the Siahkalrud area of Chaboksar. This species is reported as a new record for the flora of Iran. Native to South America, it grows outside its native range and is now established as a neophyte in several tropical and subtropical areas. The most important morphological traits of this species have been compared with those of its closely related species, O. parodiana Munz. Additionally, information on the geographical distribution, photographs of the plant, habitat, and the species' distribution in the world and Iran are provided. Furthermore, this alien species was examined and compared in terms of some invasive aspects in the world and Iran.
Introduction
Nowadays, adventive invasive species are one of the most important threats to biodiversity (Mikeladze et al., 2017). In recent years, numerous imported plants with high invasive behavior have been reported from the Caspian coasts, especially in Guilan province (Moradi, 2021). Oenothera L. is the second-largest genus in Onagraceae and consists of 145 species (Wagner et al., 2007). These plants grow in temperate to subtropical areas of America, and many of them are widely naturalized in several areas of the earth (Dietrich, 1977). The genus comprises annual, biennial, or perennial herbs, many of which occur primarily or secondarily in open habitats, including old fields, roadsides, stream sides, or dunes (Dietrich, 1977). According to the flora of Iran, two species, including O. biennis and O. laciniata, grow in Iran (Azizian, 2005) and are naturalized alien species in the country. In the present study, O. indecora Cambess. is reported for the first time from Iran. O. indecora is a species belonging to the sect. Oenothera, subsect. Munzia ser. Allochroa, which includes species with cylindrical capsules that are rarely enlarged in the upper third or somewhat petiolate, and is not fused with the subtending bract (Dietrich, 1977). This species is native to South America (Dietrich, 1977) and grows outside its native range. It is now established as a neophyte in several tropical and subtropical areas (Crisafulli et al., 2013).
Materials and Methods
During a floristic study of the Hyrcanian forests, the species was collected from the Siahkalrud area of Chaboksar in Guilan province and deposited in the Guilan Agricultural and Natural Resources Research and Education Center. The specimen was examined and identified using the flora and relevant literature (Azizian, 2005; Dietrich, 1977; Crisafulli et al., 2013).
 
Results and Conclusions
Oenothera indecora Cambess.
Annual or biennial plants are unbranched or have ascending branches arising from the rosette, 20-60 cm tall. The entire plant is sparsely long-villous with erect hairs, densely to sparsely short-villous together glandular hairs. Rosette leaves are narrowly oblanceolate, acute, 4-8 cm long, and 0.2-1.3 cm wide. Cauline leaves are narrowly elliptic to lanceolate, acute, sessile, 2.5-7 cm long, and 0.2-1.2 cm wide. Bracts are narrowly elliptic to elliptic, sessile, and either longer than or about the same length as the capsules they subtend, 1.5-5 cm long, 0.2-1 cm wide; leaves plane or undulate at the margins, irregularly serrate with blunt teeth. The inflorescence is branched. The floral tube is 0.5-1.5 cm long. Sepals are green or yellowish green, often densely flecked with reddish brown; apices of the sepals are 1-1.5 mm long, and erect. Petals elliptic to obovate, yellow, turning reddish with age, 4-10 mm long. Anthers are 1.5-4 mm long. Filaments are 1.5- 7 mm long. The style is short 1-2 cm long. Stigma lobes are 1-2 mm long. Capsules are 2-3 cm long, 1.5-2.5 mm thick; seeds elliptic to rotund in outline.
 
Examined specimens
Iran. Guilan, Chaboksar, Siahkalrud forest road, near the river, 36° 58' 55.2" N, 50° 26' 13.83" E, 180 m, 27/07/1401 and 05/08/1401, Moradi & Mahdavi (GILAN-6956, 6966).
Habitats
The species was collected on the sandy soil near a river, amidst vegetation of Alnus glutinosa (L.) Gaertn. subsp. barbata (C.A.Mey.) Yaltirik -Pterocarya fraxinifolia (Poir.) Spach. It is associated with other plants such as Geranium pyrenaicum Burm.f., Clinopodium nepeta (L.) Kuntze subsp. glandulosum (Req.) Govaerts, Sedum hispanicum L., Digitaria sanguinalis (L.) Scop., Oxalis acetosella L., Artemisia annua L., Pimpinella affinis Ledeb., Erigeron canadensis L., Hypericum perforatum L., Eryngium caucasicum Fisch. ex Steud., Phytolaca Americana L., Setaria viridis (L.) P.Beauv.

indecora, is closely related to O. parodiana, however, it is distinguished from the latter by certain morphological features. For example, the length of the bracts in the O. indecora is almost the same length as the capsule or longer than it, while in the O. parodiana, they are half of the length of the capsule or shorter. O. indecora has glandular hairs, whereas O. parodiana does not. O. indecora is native to several countries in South America. In Europe, it is known as an alien species in the Netherlands, Hungary, France, Germany, Portugal, Greece, Belgium, and Spain (Yuzbasioglu, 2014), and it was recently reported from Italy (Crisafulli et al., 2013).

 
 
In a study related to the invasiveness of Oenothera species in South Africa, it was concluded that their propensity to invade undisturbed areas potentially makes them a more serious threat than species that occur exclusively in disturbed areas. According to this, O. rosea, O. Stricta, and O. Tetraptera, as well as O. parodiana and 0. Indecora, are the species that show the greatest potential to become more problematical in the future. O. indecora (native to South America), as a neophyte species that grows in low-altitude Hyrcanian forests, could be more invasive in the future than the two species O. biennis and O. laciniata that originate from North America. There are also previous reports from Iran (Azizian, 2005; Amini & Zare, 2003) that this species grows on the sand dunes of the Caspian Sea. There is a possibility of the presence of this species in other lowland Caspian forest areas under similar vegetation conditions which needs further investigation in this field.
 
Acknowledgment
The authors of the study express their deep gratitude to Dr. Filip Verloove, a specialist in alien flora at the Belgian Botanical Garden, for his invaluable cooperation in identifying the species by confirming the photos sent. We are also thankful to Dr. Shahriar Sobh Zahedi, a researcher at the Guilan Agricultural and Natural Resources Research and Education Center, for his assistance in preparing the distribution map of the studied species.