Neurada Procumbens L. (Neuradaceae): a New Record For
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158 Plant Protection Quarterly Vol.17(4) 2002 its paripinnate leaves, calyx that is nei- ther persistent nor spiny, and the 5-celled Neurada procumbens L. (Neuradaceae): a new record ovary and fruit. for Australia and a potential threat to Australia’s Family placement sandy deserts Cronquist (1981) places Neurada in the Neuradaceae, a family native to deserts David E. AlbrechtA, Robyn M. BarkerB,C, W.R. (Bill) BarkerB,D and John in Africa, the Middle East and India. Only GavinE two other small genera, Grielum (six spp.) A Northern Territory Herbarium, Parks and Wildlife Commission of and Neuradopsis (three spp.), are included the Northern Territory, PO Box 1046, Alice Springs, NT 0871, Australia. in the Neuradaceae. The family has not [email protected] previously been recorded for Australia. Authors in the past have treated B Plant Biodiversity Centre, Dept for Environment, Heritage and Aboriginal Neuradaceae as closely allied to the Affairs, Hackney Road, Hackney, SA 5069, Australia. Rosaceae, differing from it by its distinctive C [email protected] gynoecium and its unusual bipolar pollen D [email protected] with 3–4 pores at each end. Some authors E Department of Business, Industry and Resource Development, PO Box 8760, (e.g. Meikle 1966) also accepted a broader Alice Springs, NT 0871, Australia. [email protected] circumscription of Rosaceae that included the Neuradaceae. More recent sugges- tions are that the Neuradaceae are aber- rant members of Tiliaceae in the Malvales Abstract (Huber 1993) and increasingly the affini- Neurada procumbens L. (Neuradaceae) is Northern Territory, or for that matter in ties of the family are being sought within a species from arid regions of north Afri- Australia. The plant was identified as Neu- the Malvales (Angiosperm Phylogeny ca, the Middle East and north west India rada procumbens L., a native to the sandy Group 1998, Thorne 2000), although even and is here reported for the first time desert regions of North Africa, the Middle here they can be discordant (Jansen et al. as a naturalized weed in arid Australia. East and North West India. 2000). This distinctive species is apparently As the Flora of Australia project confined to a small area on the north Description has adopted Cronquist’s system of western edge of the Simpson Desert. Prostrate annual herb to c. 1 m diameter classification (Kanis 1981), the treatment There is presently a very real chance with a very dense woolly grey indumen- of N. procumbens for that publication of eradicating the species because the tum. Leaves alternate, often fasciculate, will, presumably, be under the family population is relatively small and readily ovate, toothed or pinnatifid, 6–23 mm Neuradaceae. accessible. However, eradication may be long, 4–17 mm wide; petioles 3–15 mm only a fleeting option as the species has long; stipules linear-subulate, sometimes Extra-Australian distribution a spiny fruit that is readily dispersed absent from some leaves. Flowers small, Neurada procumbens has a Saharo- by animals, humans and vehicles, and regular, solitary in the leaf axils; pedicels Arabian phytogeographic distribution it appears to be capable of reproducing elongating to 15 mm long in fruit. Calyx 5- and is native to North Africa, the Middle in highly arid sandy situations, of which lobed, the tube constricted about the ovary East and North West India. According to there are vast tracts of suitable habitat in and bearing appendages that harden to Meikle (1966) it occurs in Algeria, Mali, arid Australia. spines after flowering, lobes 1.5–3 mm Tunisia, Libya, Egypt, NE Sudan, Ethiopia long. Petals five, 2–3 mm long, usually (Eritrea), Palestine, Israel, Jordan, possibly Introduction obovate, white, inserted at constriction Syria, Cyprus, Saudi Arabia, Iraq, Kuwait, The Simpson-Strzelecki Dunefields biore- of calyx. Stamens 10, alternating short Bahrain, Pakistan (Baluchistan), Afghani- gion is a vast, sandy area spanning arid and long, the longer ones with filaments stan and NW India (Sind, Punjab). It is parts of the Northern Territory, South c. 1 mm long, the shorter c. 0.6 mm long, also included in a list of Southern African Australia and Queensland. Few intro- inserted at constriction of calyx; anthers plants (Gibbs Russell et al. 1987) as if na- duced species have been able to establish 4-celled, 0.5 mm long. Carpels 10, tive. N. procumbens has been recorded as in this region because of the absence of 1-ovulate, united in a ring below the an invasive species in the Canary Islands permanent water, paucity of conduits calyx constriction and the stamens; in Maspalpomas Reserve on Grand (such as roads) to facilitate their arrival styles one per carpel, free, to 1 mm long, Canaria (Anon. 2000). and spread, and predominance of infertile eventually hardening, persisting on fruit; sandy soils. Only 26 introduced species stigmas capitate, 0.4 mm long. Fruit dry, Australian distribution have been recorded in the Northern Ter- indehiscent, enveloped by the hard, Neurada procumbens is presently known ritory portion of the bioregion (Albrecht spiny calyx, more or less circular with a only from the north western edge of et al. 1997) and the majority of these are flat underside, 4–7 mm high, 10–20 mm the Simpson-Strzelecki Dunefields bi- restricted to the higher rainfall edges of diameter; seeds c. 3 mm long, germinat- oregion in the Northern Territory, along the bioregion. New introduced species to ing within fruit which can be found as a the Old Andado Road between Allambi this extremely arid bioregion are of major spiny collar at the base of plants. Common and Andado homesteads (Figure 3). The concern because their establishment and names – pata camello, chapari (India); an- species is naturalized in this area and persistence is indicative of the weedy po- fel, sa’adan (Africa) (Figures 1 and 2). occurs as a single linear metapopulation tential of these species in the broader arid Neurada procumbens is a distinctive spe- approximately 13 km long following the region of Australia. cies that looks superficially like a member road alignment. The metapopulation is In June 2000 a prostrate grey herb was of the Malvaceae. In central Australia comprised of several discontinuous sub- found growing along track verges be- it could be confused with Tribulus (Zy- populations. Extensive searches for the tween Andado and Allambi homesteads gophyllaceae) because of its prostrate species elsewhere in the bioregion have in southern Northern Territory. The plant habit and spiny fruit. However, Tribulus not been undertaken. had not previously been collected in the is readily distinguished from Neurada by Plant Protection Quarterly Vol.17(4) 2002 159 E E1 F F C G D1 I D G H J3 J J2 J1 K Figure 2. Neurada procumbens. Coincidentally, the first camels intro- B duced to Australia were also from the Canary Islands (McKnight 1969). The introduction of N. procumbens to Australia via camels seems unlikely however con- sidering the following points. The last im- portation of camels from overseas was in 1907 (P. Siedel personal communication), therefore if fruit arrived via camels from overseas the population would have to be over 94 years old. The infestation is unlike- ly to be this old considering the relatively A small area that it occupies and the fact that biological surveys in the vicinity approxi- mately 15 years ago failed to record or collect the species (P. Latz personal com- munication). If the conditions were dry at Figure 1. Neurada procumbens (all drawn from P.Horsfall 951) A, habit of the time of the survey it may have been 2 plant, from above (× /3); B, plant from below with spiny encircling fruit overlooked. However, if conditions were 2 still present (× /3); C, upper surface and lower leaf surfaces (×2); D, flower suitable for growth, the plants would have with enclosing calyx, lateral view and D1, flower from above (×2); E, calyx been obvious because of their distinctive lobe, inner surface (×7); E1, calyx lobe, outer surface (×7); F, petals (×7); appearance and the occurrence along the G, stamens, front and back views (×12); H, style and stigma (×12); I, half main vehicular track through the area. Although introduction via camels seems view of flower showing carpels with included ovules, stamens, styles and unlikely, we need a better understanding petal bases (×7); J, mature fruit, from above (×1.5); J1, mature fruit from of the long term viability of the fruits and side (×1.5); J2, mature fruit from below (×1.5); J3, cross section of mature the behaviour of plants before this can be hardened fruit showing seeds (×1.5); K, seed (×3). totally ruled out. It is possible that a small population could persist as soil-stored fruit during prolonged dry periods with- out being noticed. Specimens Possible explanations for occurrence If camels are ruled out, the most likely Northern Territory. 22 km due S of Todd It is tempting to hypothesize that N. explanation is introduction via overseas River Downs, 24°26’10”S 135°11’56”E, 15 procumbens arrived in arid Northern Ter- visitors (e.g. tourists, film crews). Fruits June 2000, D.E.Albrecht 9676 (NT, DNA); ritory via camels, given the fact that it is could adhere to sleeping bags, socks, 102 km S of Santa Teresa on the Andado native to the same region from which cam- clothing etc. and it is possible that cloth- Road and 5 km SE of the Arookara Range els were imported into Australia, and the ing or camping equipment used in Africa/ Gate, 24°22’25”S 135°08’01”E, 6 Sept long history of camels in central Australia. India may have dropped fruit when used 2000, P.Horsfall 951 (NT, DNA, MEL, AD, Camels are known to disperse the fruit of here.