Newly Recorded Alien Species of Ficus L. (Moraceae) in Java, Indonesia

ABSTRACT Ficus is the largest genus in the Moraceae family, with the syconium inflorescence as its characteristic. This genus has a wide distribution worldwide, and about 367 species were found in the Malesia region. There are 74 species have been recorded on Java, and seven species are known as introduced plants. Based on our recent observations in West Java, Central Java, Yogyakarta, and East Java, three newly recorded Ficus species were found, namely F. auriculata Lour., F. maclellandii King, and F. natalensis subsp. leprieurii (Miq.) C.C. Berg. The species were introduced to Java as an ornamental plant. Descriptions, photographs, and a brief discussion of the three newly recorded species are presented in this manuscript.


INTRODUCTION
Ficus L. is the largest genus in the Moraceae and it separated taxonomically from other genera into the Ficeae Gaudich tribe. Morphologically, the genus is characterized by its figs. The flowers are both unisexual and bisexual and are located in the receptacle base (Backer & Bakhuizen van den Brink 1965;Berg & Corner 2005). Ficus has a wide distribution area in the world, especially in tropical and subtropical regions. The genus consists of 735 species and 367 species found in the Malesia region (Berg & Corner 2005). The information on the diversity of Ficus species in Java has been compiled by Backer & Bakhuizen van den Brink (1965) and Berg & Corner (2005). As many as 74 species of Ficus are found on the island and seven of them are introduced plants, namely F. benghalensis L., F. callosa Willd., F. carica L., F. lyrata Warb., F. pumila L., F. religiosa L., and F. rumphii Blume (Backer & Copyright: © 2021, J. Tropical Biodiversity Biotechnology (CC BY-SA 4.0) Bakhuizen van den Brink 1965; Berg & Corner 2005). Since then, the updated information on the genus Ficus in Java, including the newly introduced species, has not been provided yet.
In recent years, many non-native species were reported from Java by many authors (e.g. Girmansyah 2014;Mustaqim & Nisyawati 2016;Irsyam & Mountara 2018;Hariri et al. 2019;Irsyam et al. 2019;Anshori et al. 2020;Hariri et al. 2020;Effendi & Mustaqim 2021). It shows that the number of non-native plant species in Java will continue to increase. In this study, we report the occurrence of three newly recorded species, namely F. auriculata Lour., F. maclellandii King, and F. natalensis subsp. leprieurii (Miq.) C.C. Berg, for Java. The study was also conducted to provide an updated taxonomic data on the genus Ficus in Java.

Materials
The study was carried out in several locations in West Java (Bandung, Bogor, Sumedang, Subang), Central Java (Kebumen), Jogjakarta, and East Java (Malang, Surabaya, Banyuwangi, Madura Island) from September 2019 to December 2020. The materials used in this study were specimens stored in the Herbarium Bogoriense (BO), field-collected specimens, and noncollected specimens grown in Bogor Botanic Gardens (BBG).

Methods
The field observations used exploring method following Rugayah et al. (2004), while the sampling method following van Balgooy (1987). The syconia were also collected as wet specimens preserved in 70% ethanol. The other data recorded were the locations, names of collectors, collection numbers, coordinate points, morphological features that could be lost during the preservation process (the color of latex, indumentum, leaves, and syconia), vernacular names, and their utilization.
The specimens collected from the field were taken to the Bandungense Herbarium (FIPIA), School of Life Sciences and Technology, ITB, to be processed into herbarium specimens following Djarwaningsih et al. (2000). The samples were also re-identified using Flora Cochinchinensis 2 (Loureiro 1790), Checklist of Ficus in Asia and Australasia with keys to identification (Corner 1965), Flora Malesiana Ser. I Vol 17 (2) (Berg & Corner 2005), New Taxa and Combinations in Ficus (Moraceae) of Africa (Berg 1988), and Taxonomic treatment of the Ficus auriculata complex (Moraceae) and typification of some related names .

Ficus maclellandii
F. auriculata has a gynesic flowering system , without adventitious roots, syconium grows cauliflory or on specialized branches and is also found in the root (stoloniflory), 2 stamens, and 1 the stretching of the pistil (Figure 2). Previous research has shown that subg. Sycomorus found in Java consisted of 8 species, namely F. fistulosa Reinw. ex Blume, F. hispida L.f., F. lepicarpa Blume, F. racemosa L., F. ribes Reinw. ex Blume, F. septica Burm.f., F. variegata Blume, and F. vrieseana Miq. (Backer & Bakhuizen van den Brink 1965;Berg & Corner 2005). Field observations have been carried out at several locations in Java, and however, F. auriculata was only found from Bogor, Malang, and Madura Island. The existence of this species in Java has never been registered before. Therefore, this finding will increase the number of Ficus subg. Sycomorus members for Javanese flora information to be nine species. Ficus auriculata is an introduced plant originating from India and mainland Southeast Asia, while the remaining eight species are naturally distributed in the Malesia region (Berg & Corner 2005).
Ficus auriculata was introduced to Java through the Bogor Botanical Gardens in 1823, under the name F. macrocarpa H.Lév. & Vaniot. Data on the dynamics of F. auriculata in the Bogor Botanical Gardens are shown in Table  1. Traceable collections of F. auriculata in the Bogor Botanical Gardens, namely collections in plot VII.G.139 collection. The collection originated from the Himalayas, India, and was planted from grafts from June 1956 to 1985. Currently, the collection is dead. However, field observations indicate the existence of one non-collected F. auriculata individual in plot VII.G. This non-collected plant species is thought to have grown spontaneously from the dead vegetative part (stem) of the previous collection.  Boldingh (1914); Boldingh (1916); Dakkus (1930); Setyodiwiryo (1957); Sastrapradja (1973); Danimihardja & Notodihardjo (1985).
In general, F. auriculata is known by the community as the African tin trade name. However, this species is different from the true tin, namely F. carica L. Both species are taxonomically assigned to two different subgenera. Ficus auriculata is a member of the subg. Sycomorus, while F. carica belongs to the subg. Ficus. Morphologically, both have distinguishable characteristics ( Ficus maclellandii and F. natalensis subsp. leprieurii are a monoecious plant , which include to subg. Urostigma. However, they both from different sections, where F. maclellandii in the sect. Urostigma, which distributed from Africa to the Pacific, while F. natalensis subsp. leprieurii in the sect. Galoglyphic, which is indeed the endemic section of Africa (Berg & Corner 2005).
Currently, F. maclellandii is widely cultivated and planted as a roadshading tree. The tree canopy is rounded and a thick canopy, so, it is potential as a noise damper and pollution absorber. Recent studies show that F. maclellandii have important ecological roles, such as providing habitat and nesting sites of birds in urban areas (Sulaiman et al. 2013). Naturally, this species is only distributed in India, China, and mainland Southeast Asia but it has been introduced to other tropical regions, including Indonesia. Most of the F. maclellandii specimens collected in Java did not produce generative organs, except for the PJBMTW0919-005 specimens from Bekasi. Following previous research, the species is sterile and rarely produces flowers, so, propagation is prepared through the stem cutting method (Berg 2007). Ficus maclellandii belongs to Ficus subg. Urostigma, because of air roots on its branches (Figure 3), its closely related to F. binnendijkii (Miq.) Miq. (Berg & Corner 2005;Berg 2007). All of the F. maclellandii specimens collected from Java hairy on its leaf base and have pinnate venation. These two are the main different characteristics between F. maclellandii and F. binnendijkii (Berg & Corner 2005;Berg 2007). Three species of exotic Ficus originating from Africa, namely F. cyathistipula Warb., F. lyrata Warb., and F. natalensis Hochst., have been introduced to the Malesia region as ornamental plants (Berg & Corner 2005). However, records of herbarium specimens of these three species are not available yet (Berg & Corner 2005). During the study specimens of F. natalensis subsp. leprieurii was not found at the Bogorinese (BO) Herbarium. Therefore, F. natalensis subsp. leprieurii was collected from Java for the first time. Morphologically, this species has flattened and shiny leaflets and is similar to F. deltoidea Jack. The two species can be distinguished based on the presence of wax glands on the leaves. The abaxial surface of F. deltoidea leaves has black wax glands in the axillary part of the vein (Figure 4-I). Meanwhile, the wax gland structure was not found in the leaves of F. natalensis subsp. leprieurii (Figure 4-H).

CONCLUSION
The additional notes, three species of the Ficus as introduced plants in Java can increase the number of species diversity of Ficus spp. Besides having potential as ornamental plants, F. auriculata, F. maclellandii, and F. natalensis subsp. leprieurii have other prospects that can be studied further in the future.