Differential habitat affinities of five species of fruitpiercing moths (Lepidoptera: Noctuidae) in their utilization of Tinospora smilacina Benth. as a larval host plant in north Queensland

Abstract

Three habitats, each containing a diflferent form (rainforest, coastal and dry tropics) of the twining vine Tinospora smilacina, and a fourth with two of these forms were routinely sampled between 1986 and 1989 for larvae of fruitpiercing moths, to ascertain spatial and temporal utilization of this plant, Othreis fullonia and Othreis materna occurred on all forms in all habitats, predominantly between November and March for the former and January to June for the latter. Although Rhytia cocalus utilized two forms of T. smilacina it preferred the rainforest habitat to which Othreis jordani and Khadira aurantia were essentially confined. While the degree of cohabitation between any two moth species was greatest in the drier inland habitat, where only O. materna and O. fullonia occurred during a limited season, there was considerable temporal separation of any two species utilizing T. smilacina in any habitat. Field and laboratory evaluation of alternative menisperm hosts suggested O. fullonia, O. fordani and K. aurantia were generalists while O. materna and R. cocalus confined their feeding to the genus Tinospora. The differential habitat affinities and host plant acceptance of these moths are pertinent to their variable seasonal activity, local importance and general pest status.

The relative acceptabilities of three Australian Menispermaceae as food plants for larvae of the fruitpiercing moth, Othreis fullonia

“…While the choice experiment indicated that young larvae are unlikely to select or move onto less preferred hosts (Table 2), older larvae will accept and develop satisfactorily on these plants, even after an earlier experience on a preferred host. Rainforest affords a good opportunity for host-switching, as six or more menisperm species have been observed coexisting in one area (Fay & Halfpapp, 1993a). Rainforest affords a good opportunity for host-switching, as six or more menisperm species have been observed coexisting in one area (Fay & Halfpapp, 1993a).…”

“…Over the remainder of its range including Australia its hosts are climbing plants of the family Menispermaceae (Tryon, 1898;Hargreaves, 1936;Banziger, 1982). Where O. fullonia breeds on menisperms it utilizes a large number of genera (Mosse-Robinson, 1968;Banziger, 1982) while some other fruitpiercing moths, such as Othreis materna (L.) and Eudocima salaminia (Cramer), confine their larval feeding virtually to a single genus (Sands & Schotz, 1989;Fay & Halfpapp, 1993a). Where O. fullonia breeds on menisperms it utilizes a large number of genera (Mosse-Robinson, 1968;Banziger, 1982) while some other fruitpiercing moths, such as Othreis materna (L.) and Eudocima salaminia (Cramer), confine their larval feeding virtually to a single genus (Sands & Schotz, 1989;Fay & Halfpapp, 1993a).…”

“…These plants are distributed throughout coastal regions of much of eastern Australia and differentially across the north of the continent, coexisting in some habitats (Fay & Halfpapp, 1993a), Host-switching by individual larvae has been observed in glasshouse colonies (Fay, unpubl. The three menisperms chosen were Tinospora smilacina Benth., Sarcopetalum harveyanum F. Muell.…”

“…The relationship between these two plant groups is thought to be the similar alkaloids they possess (Thornber, 1970). Where O. fullonia breeds on menisperms it utilizes a large number of genera (Mosse-Robinson, 1968;Banziger, 1982) while some other fruitpiercing moths, such as Othreis materna (L.) and Eudocima salaminia (Cramer), confine their larval feeding virtually to a single genus (Sands & Schotz, 1989;Fay & Halfpapp, 1993a). Recent work in Thailand and Australia now suggest O. fullonia prefers particular hosts, and those of the genus Tinospora are considered principal amongst them (Banziger, 1982;Fay & Halfpapp, 1993a).…”

“…Where O. fullonia breeds on menisperms it utilizes a large number of genera (Mosse-Robinson, 1968;Banziger, 1982) while some other fruitpiercing moths, such as Othreis materna (L.) and Eudocima salaminia (Cramer), confine their larval feeding virtually to a single genus (Sands & Schotz, 1989;Fay & Halfpapp, 1993a). Recent work in Thailand and Australia now suggest O. fullonia prefers particular hosts, and those of the genus Tinospora are considered principal amongst them (Banziger, 1982;Fay & Halfpapp, 1993a). Other menisperms, such as those of the genera Sarcopetalum and Tiliacora, seem readily accepted by larvae but are utilized less frequently than Tinospora.…”