Libocedrus is a small genus of five species of coniferous trees in the cypress family Cupressaceae (order Pinales), native exclusively to New Zealand and New Caledonia. The two New Zealand species — kawaka (Libocedrus plumosa) and pāhautea (Libocedrus bidwillii) — are sometimes collectively called New Zealand cedars, a reflection of their aromatic timber and cedar-like appearance rather than any close relationship to true cedars.
The genus is closely allied to the South American genera Pilgerodendron and Austrocedrus, and to the New Guinean Papuacedrus, all of which some botanists subsume within a broader Libocedrus. More distantly, the group resembles the Northern Hemisphere genera Calocedrus and Thuja; historically, what is now Calocedrus was sometimes placed within Libocedrus, but molecular work (Gadek et al., 2000) confirmed the two lineages are far less closely related than their morphology suggests.
Foliage consists of small, scale-like leaves 3–7 mm long, arranged in apparent whorls of four — technically opposite decussate pairs spaced unevenly so that successive pairs alternate between closely set and widely set. Female cones are 8–20 mm long and carry just two pairs of moderately thin, erect scales; each scale bears a prominent spine 3–7 mm long on its outer face and two winged seeds on the inner face.
The wood is soft, moderately durable, and notable for a spicy-resinous fragrance. Both New Zealand species have been used for timber and are planted as ornamentals outside their natural range.
Etymology
The name Libocedrus derives from the Greek libo- ("teardrop") combined with cedrus ("cedar"), a reference apparently to the resinous drops exuded by the trees. No individual common name is recorded for the three New Caledonian species; the two New Zealand species go by their Māori names kawaka (L. plumosa) and pāhautea (L. bidwillii).
Distribution
Libocedrus is confined to two isolated island regions of the South Pacific: New Zealand (two species) and New Caledonia (three species). The genus is part of a broader Southern Hemisphere lineage that also includes the South American Pilgerodendron and Austrocedrus and the New Guinean Papuacedrus, reflecting an ancient Gondwanan distribution.
Taxonomy Notes
Libocedrus belongs to the family Cupressaceae, order Pinales. Its circumscription has varied: Calocedrus was historically included within it, and some treatments expand Libocedrus to absorb Pilgerodendron, Austrocedrus, and Papuacedrus. Molecular phylogenetic analysis (Gadek et al., 2000) resolved these relationships, demonstrating that Calocedrus and Thuja are not closely allied to Libocedrus despite morphological convergence. GBIF recognises five accepted species within the genus.
