The roles of lizards in New Zealand plant reproductive strategies

Abstract

Geckos in the genus Hoplodactylus regularly visit flowers to feed on nectar. They collect considerable amounts of pollen, mostly on their throats, from species such as Metrosideros excelsa and Phormium tenax. This pollen can be carried for many metres and for up to at least 12 hours, and there is thus the opportunity for lizards to transfer it to a conspecific plant to effect crosspollination.Geckos in the genus Hoplodactylus and skinks in the genera Leiolopisma and Cyclodina all include considerable quantities of fleshy fruit in their diet during summer. Fruits most commonly consumed are in the genera Coprosma, Gaultheria, Hymenanthera, Macropiper, and Muehlenbeckia. Seeds pass through the gut undamaged and germination trials showed that at least some are viable. Because of the size, colour, and positioning of the fruit it appears that some divaricating shrubs (e.g., Coprosma, Hymenanthera) or vines (e.g., Muehlenbeckia) may be specifically adapted to seed dispersal by lizards.

The importance of lizards as frugivores and seed dispersers.

“…Whitaker (1968) recorded 73 m as the maximum distance movement by Hoplodactylus duvaucelli (Gekkonidae) in New Zealand. This author also found dispersed seeds 12 m away from the nearest fruiting plants (Whitaker, 1987). Barquín and Wildpret (1975) cited up to 50 m for seeds of Plocama pendula (Rubiaceae) being dispersed by Gallotia galloti from the nearest potential parent plant.…”

“…Klein, 1977;Janzen, 1982;Iverson, 1985;Traveset, 1990;Hartley et al, 2000) and the omnivorous ones (e.g. Whitaker, 1987;Fialho, 1990;Valido and Nogales, 1994;Willson et al, 1996;Lord and Marshall, 2001;Olesen and Valido, 2003;Rodríguez-Pérez et al, 2005).…”

Floral biology and breeding system of pohutukawa (Metrosideros excelsa, Myrtaceae)

“…The inflorescences are set on the periphery of the canopy and bear hermaphrodite, large, red brush flowers that produce copious nectar. Flower visitors include the native New Zealand honeyeaters (Meliphagidae) (Angehr 1986), a range of introduced birds (Anderson 1997), native and introduced bees (Donovan 1980;Salmon 1980), and also geckos and bats (Whitaker 1987;Eifler 1995;Arkins 1996). Seed production in pohutukawa is reported to be generally low, and the majority of the seeds are sterile (Dawson 1968(Dawson , 1970a.…”

A test for ultraviolet reflectance from fleshy fruits of New Zealand plant species

“…In this study we compare UV reflectance of fruits of 41 indigenous species having a range of perceived fruit colours, life-forms, and taxonomic affiliations. Most of the species are dispersed by birds, although Whitaker (1987) has suggested that small lizards are primary dispersers of many white or translucent fruits flecked with pale blue or pale pink. Small-leaved Coprosma species at low altitudes characteristically have nonred fruit colours which may also be preferred by nectarivorous birds (Lee et al 1988).…”

“…28 1980), have UV VISIOn. Melicytus alpinus* (Violaceae) was included in this study as Whitaker (1987) considers it to be dispersed primarily by small lizards, although there is no evidence that these animals can detect UV.…”