Cassytha filiformis: A Parasitic Plant targetting Insects.

Parasirism is very common in the natural world, with many species of Prokaryotic and single-celled Eukaryotic life-forms relying on the strategy, Fungi frequently parasitising Animals, Plants and other Fungi, Animals parasitising other Animals and Plants, and Plants parasitising both other Plants and Fungi. However, Plants, whilst occasionally directly consuming Animals (carnivory) do not generally parasitise Animals.

In a paper published in the journal Current Biology on 20 August 2018, Scott Egan, Linyi Zhang, Mattheau Comerford, and Glen Hood of the Department of BioSciences at Rice University describe an example of parasitism of Animals by Plants, a trophic interaction which they suspect, while not previously recorded, may in fact be widespread in nature.

Egan et al. were inspecting Sand Live Oaks, Quercus geminata, targetted by the parasitic Love Vine, Cassytha filiformis, in a native scrub habitat in southern Florida, when they observed that the galls (tumors induced by the action of a parasitc Animal on a Plant, in which the Animal, typically a larval Arthropod, lives, protected by the gall tissue and feeding on the fluids of the host Plant) of two parasitic Wasp species, Belonocnema treatae and Callirhytis quercusbatatoides, were penetrated by the haustoria (root like projection from a Parasitic Plant, that penetrates the tissues of the host) of the vine. This was despite the fact that the galls of these Wasps are located on the underside of the leaves, an area not usually targeted by the Vine, suggesting that this food source is actively sought out, rather than being attacked purely by chance.

(A) Cassytha filiformis Vine attaching haustoria to a leaf gall induced by the Wasp Belonocnema treatae on the underside of their host Plant, Quercus geminata. (B) Labeled graphic of Insect gall, parasitic Vine, and Vine haustoria. Egan et al. (2018).

The galls of Belonocnema treatae attacked by the Vine were on average 35% larger than those that were not, though this appeared to be driven by the Vine not attacking smaller galls, with no gall smaller than 3.5 mm in diameter, being attacked, rather than the Vine causing larger galls. Inspection found 45% of parasitised galls contained a dead and mummified Wasp, compared to just 2% of non-parasitised galls, suggesting the interaction had a highly adverse effect on the Wasps. A wider inspection of the area found the Vine was parasitising the galls of a further four species of Wasps, Andricus quercuslanigera, Neuroterus minutissimus, Disholcaspis quercusvirens, and Andricus quercusfoliatus, as well as the Gall Midge Arnoldiola atra.

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Alseodaphnopsis ximengensis: A new species of Laurel from Yunnan Province, China.

Laurels, Lauraceae, are evergreen Dicotyledonous Plants found in tropical and warm temperate zones around the world, though they are most diverse and abundant in Southeast Asia and tropical America, where they form an important component of tropical rainforests. Most Laurels are evergreen trees, though one genus, Cassytha, comprises parasitic vines. Laurels appeared some time in the Cretaceous, though opinions about how early vary. These plants are fruit-producers, typically relying on Birds to spread their seeds.

In a paper published in the journal PLoS One on 18 October 2017, Yue-qing Mo of the Plant Phylogenetics & Conservation Group at the Xishuangbanna Tropical Botanical Garden, and the University of the Chinese Academy of Sciences, Lang Li, also of the Plant Phylogenetics & Conservation Group at the Xishuangbanna Tropical Botanical Garden, Jian-wu Li of the Herbarium of the Xishuangbanna Tropical Botanical Garden, Jens Rohwer of the Biozentrum Klein Flottbek at Universität Hamburg, Hsi-wen Li of the Herbarium at the Kunming Institute of Botany, and Jie Li, again of the Plant Phylogenetics & Conservation Group at the Xishuangbanna Tropical Botanical Garden, describe a new species of Laurel from Yunnan Province in China, as part of a review of the Persia group of genera (which includes Avacados and their close relatives).

The new species is named Alseodaphnopsis ximengensis, where 'Alseodaphnopsis' refers to the similarity of the genus to the previously described genus 'Alseodaphne', and 'ximengensis' means 'from Ximeng' the species having been discovered in Ximeng County of Yunnan Province. The species forms evergreen trees with leathery leaves up to 11 cm in length,small white flowers and globular fruit up to 4.7 mm in diameter. The species was found growing in a seasonal rainforest at an altitude of 1300 m.

Alseodaphnopsis ximengensis. (A) Branchlet with inflorescences; (B) Branchlet with immature infructescences; (C) Branchlet with mature fruits; (D)-(F). Mature fruits; (G)-(H). Flowers. Jian-wu Li in Mo et al. (2017).

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Cinnamomum bladenense: A new species of Cinnamon from southern Belize.

Cinnamons, Cinnamomum spp., are tropical trees in the Laurel Family, Lauraceae, best known for their aromatic bark, which is widely used to flavour food. There are currently about 350 known species of Cinnamon tree, most of which are found in tropical Asia, though 47 species have been described from the tropical forests of Central and South America.

In a paper published in the journal PhytoKeys on 7 June 2017, Steven Brewer of the Belize Foundation for Research and Environmental Education, and Gail Stott of the Department of Plant Sciences at the University of Oxford, describe a new species of Cinnamon from the Bladen Nature Reserve in southern Belize.

The new species is named Cinnamomum bladenense, where ‘bladenense’ means ‘from Bladen’ in reference to the Bladen Nature Reserve (this reserve in turn takes its name from the Bladen River, though the ultimate derivation of the name is unknown). It is a tall canopy tree (unusual for a Cinnamon) reaching 25 m in height, with flowers unusually small for the genus. It has a straight, round, trunk supported by buttress roots, the bark is grey with a pinkish cast, which when damaged reveals a pinkish brown under-layer with a strong soapy odour, reminiscent of a bathroom cleaner. The leaves are waxy, 35-86 mm in length and 11-31 mm wide, flowers are brown-to-black, roughly 5 mm in length and born on leaf axils 40-80 mm in length and covered in grey hairs. 

Diagnostic vegetative characters of Cinnamomum bladenense. (A) Branch showing adaxial surface and variation of leaf sizes within branches. (B) Abaxial surface of leaves showing matte green laminae and prominent midvein and secondary venation. (C) Young twigs moderately and minutely sericeous with whitish buds. (D), (E) From the base of the same leaf lamina, respectively, adaxial surface of secondary vein axils not ampullous, abaxial surface of secondary veins barbellate and plane with the lamina surface. Steven Brewer in Brewer & Stott (2017).

The species is described from less than ten trees found growing on a pair of limestone ridges (an unusual location for a Cinnamon) south of the Bladen River. These locations are slightly upstream of the stretch where the river descends onto the coastal plain, and are on steep, well drained slopes in semi-evergreen forest. No further trees were found in the Bladen Nature Reserve, but similar environments are known to the southwest, close to the border with Guatemala, and to the northeast along the foothills of the Maya Mountains, as far as the southeastern portion of the Cockscomb Basin. For this reason the conservation status of Cinnamomum bladenense is unknown, though Brewer and Stott note that while the Bladen Nature Reserve is theoretically protected, it is prone to illegal logging and burning.

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