Decision Date 7 January 2020 Application number APP203950 To import for release any new organism under section 34 of the Application type Hazardous Substances and New Organisms Act 1996 Applicant New Zealand Plant Producers Incorporated (NZPPI) Date Application received 9 December 2019 Acting Chief Executive, Environmental Protection Authority Considered by (EPA) To release the tropical houseplant Rhaphidophora tetrasperma, Purpose of the application otherwise known as Philodendron ‘Minima’ or Mini Monstera, without controls The new organism approved Rhaphidophora tetrasperma Hook.f. Summary of the decision Application APP203950, to import for release Rhaphidophora tetrasperma is approved, without controls, having been considered in accordance with the relevant provisions of the Hazardous Substances and New Organisms (HSNO) Act 1996 (the Act) and the HSNO (Methodology) Order 1998 (the Methodology). 1 Application and consideration process Legislative criteria for application 1.1 The application was lodged pursuant to section 34(1)(a) of the Act. Unless otherwise stated, references to section numbers in this decision refer to sections of the Act. The decision was made in accordance with section 35, taking into account additional matters to be considered under section 36, and matters relevant to the purpose of the Act, as specified under Part 2 of the Act. 2 Decision APP203950 1.2 Consideration of the application followed the relevant provisions of the Methodology. Unless otherwise stated, references to clauses in this decision refer to clauses of the Methodology. Receipt of application 1.3 Application APP203950 was formally received by the Environmental Protection Authority (EPA) for consideration on 9 December 2019. Statutory criteria for pathway assessment – s35(1) 1.4 The decision to undertake a rapid assessment under section 35(1) of the Act has been delegated to the EPA’s Manager of New Organisms (MNO). The MNO has assessed the application against the statutory criteria in section 35(2) and 35(3) of the Act and concluded that it is reasonable to assume that it meets the criteria for a rapid assessment. Therefore, a rapid assessment under section 35 of the Act is appropriate. Decision-maker 1.5 In accordance with section 35(2) and 35(3) of the Act, the EPA has delegated to me, the acting Chief Executive, the power to conduct a rapid assessment under section 35 of the Act. Purpose of the application 1.6 The applicant, New Zealand Plant Producers Incorporated (NZPPI), applied to the EPA to import for release the tropical plant species, Rhaphidophora tetrasperma, for commercial purposes to diversify New Zealand’s indoor tropical plant market. 2 The organism 2.1 Rhaphidophora tetrasperma is a tropical plant species native to Malaysia and Indonesia and is limited to Peninsular Malaysia (Kelantan and Perak regions) and the far south of Thailand. It is known by many names including Philodendron ‘Minima’ or Mini monster. 2.2 Taxonomy of Rhaphidophora tetrasperma: Clade: Monocots Order: Alismatales Family: Araceae Genus: Rhaphidophora Species: tetrasperma Hook.f. 2.3 Rhaphidophora tetrasperma is one of approximately 100 species within the genus Rhaphidophora which is one of the largest aroid genera in tropical Asia (Boyce, 1999). It occurs naturally on disturbed, dry to wet tropical forests on sandstone and granite (Kew, 2019). January 2020 3 Decision APP203950 2.4 It is a small to medium-sized, slender, heterophyllus1 climbing liane2 reaching up to five metres in length. Scientific reports on this species are limited and details of its reproductive biology are absent. 2.5 The scientific literature suggests that species within the Aroideae genera require specialised pollinators from Hymenoptera to facilitate seed production (Gibernau, 2011). Without its co- evolved pollinating insects and therefore the ability to set seed, the plants cannot reproduce so it is considered that R. tetrasperma will not be able to establish self-sustaining populations in New Zealand. Furthermore, fruiting of R. tetrasperma has not been observed from specimens at Kew Gardens, United Kingdom (Kew, 2019). Comments from DOC and MPI 2.6 In accordance with section 58(1)(a) of the Act, the Department of Conservation (DOC) and the Ministry for Primary Industries (MPI) were provided with the application and asked for comment. 2.7 DOC stated that R. tetrasperma could potentially establish in the natural environment for example Northland, but, not in other regions of New Zealand under current temperatures. Climate change could however alter the risk of this species and enable it to establish elsewhere. 2.8 DOC stated that R. tetrasperma is likely to grow at sites where it has been dumped but there are no obvious pathways for spread from these sites and growth is not likely to be vigorous. DOC stated that the intention of using R. tetrasperma for indoor purposes should greatly reduce the likelihood of illegal dumping but not preclude it entirely. 2.9 DOC stated that they consider the likelihood of this species becoming a serious environmental weed to be low (but not zero and with the proviso that climate change could heighten the risk). 2.10 DOC stated that they do not oppose the release of R. tetrasperma. 2.11 MPI referenced two blogs by Lucas (2019) and Russell (2018) which stated that growers consider R. tetrasperma to be ‘very invasive despite the fact it is considered moderately rare in nature’. This statement referred to greenhouse experiences in temperate environments; however, could be relevant to outdoor conditions in mild to tropical climates. 2.12 MPI noted that another related member of the monsteroid family, Monstera deliciosa, has become mildly invasive in many areas of New Zealand, even though (apparently) it is not known to set seed in the absence of a pollinator similar to R. tetrasperma. 2.13 MPI noted that the applicant has stated that ‘there are no known risks from the release of R. tetrasperma in New Zealand’. MPI noted that while this may be true, very little is known about 1 Heterophyllus: having the foliage leaves of more than one form on the same plant or stem. 2 Liane: a climbing or twining plant January 2020 4 Decision APP203950 R. tetrasperma particularly in relation to hardiness, temperature requirements and its ability to thrive outside its known natural distribution. 2.14 MPI stated that it is unlikely that R. tetrasperma will propagate through the production of seed and the applicant provides good evidence to support this contention. Propagation through cuttings is obviously readily possible and it appears that this is a key means of producing further plants in commercial trade settings. MPI noted that it is entirely possible that R. tetrasperma could naturally propagate via stem segmentation through natural breakage of internodes particularly when placed into novel environments where seed propagation is unfavourable. 2.15 MPI noted that while information regarding this species is relatively poor, it appears that it has the capability to survive in a wide variety of climatic conditions in New Zealand, even those at low temperatures. MPI concluded that if R. tetrasperma does establish, it may be relatively easy to eradicate but this is an entirely unknown factor given the paucity of information on the species. Information available for the consideration 2.16 The information available for my consideration comprised: the application and references provided therein; the EPA Staff Assessment Report; comments received from DOC and MPI; and a memorandum from the EPA to support decision-making. 3 Consideration Sequence of consideration 3.1 In accordance with clause 8 of the Methodology, the information provided from the sources listed in section 2.16 above was considered when reaching this decision, followed by the taxonomy/identification and the biological characteristics of the organism. 3.2 In accordance with section 35 (rapid assessment of risk for importation of new organisms) of the Act, potentially significant risks have been identified and assessed, with particular reference to the matters set out in sections 35 and 36 of the Act. The matters set out in Part 2 of the Act, were also considered. Any Part 2 matters requiring further discussion are detailed below. Is R. tetrasperma an unwanted organism? 3.3 Rhaphidophora tetrasperma is not an unwanted organism as defined under the Biosecurity Act. Ability to form self-sustaining populations and ease of eradication 3.4 In accordance with section 35(2)(b)(i) of the Act, the ability of the organism to establish a self- sustaining population, and the ease of eradication of such a population should it establish has been considered. January 2020 5 Decision APP203950 3.5 I considered the possibility that should R. tetrasperma be approved for release without controls in New Zealand, it would permit any individual in New Zealand to import this species for private use or wholesale distribution for both indoor and outdoor settings. 3.6 The scientific literature on R. tetrasperma is scarce. No information was found to support R. tetrasperma being an invasive or pest species. 3.7 The native geographic distribution of R. tetrasperma is in the tropical south-eastern Asian countries of Malaysia and Indonesia. The natural habitats that it thrives in are dry to wet rainforests that have high humidity, high annual average rainfall of 2,500mm and an average temperature of 27ºC. The temperature in its native climate does not fall below 18ºC even during the cooler season. 3.8 The equatorial climate of Peninsular Malaysia and south Thailand, where R. tetrasperma is endemic, is comparable to United States Department of Agriculture (USDA) Hardiness Zone 13. New Zealand’s maximum Hardiness Zone rating is 11. 3.9 As information on this species is limited, we can use a related tropical Rhaphidophora species, Rhaphidophora decursiva as a proxy for R. tetrasperma. Rhaphidophora decursiva is a tropical species which has been present in New Zealand for many years, produces flowers and survives outdoors in Northland.