Clusia L.

Plate from Handlirsch (1884) showing wings of Clusia species: C. tigrina (figure 9), C. flava (figure 10)

   

Clusia Haliday (which now includes Paraclusia Czerny and Amuroclusia Mamaev (Lonsdale & Marshall, 2008)) occurs in the Holarctic and Oriental Regions and is comprised of 13 species. Several of these large, showy species are quite commonly encountered in North America and Europe, and consequently, have been discussed at length in the scientific literature over the past 150 years. The family name "Clusiidae" (spelled "Clusiinae" at the time) was even derived from the genus name containing the two frequently-collected European species, C. tigrina and C. flava, by Handlirsch in 1884 (see plate from original publication to right).

Adults are often found on a wide range of deciduous tree species (observations on conifers such as pine and spruce are much less frequent), preferring either stumps or dead, bare wood on standing trunks (Rohácek, 1995; Stubbs, 1982, personal obs.). Stubbs (1982) found adults of C. tigrina most often in August and September on barkless spots of live beech trees.

European Clusia have been reared from the stumps of several deciduous species such as beech, birch and elm (Perry & Stubbs, 1978; Smith, 1950), and have occasionally been reared from conifers (Soós, 1981). North American adults have been reared from 'moist wood', 'dead Populus tremuloides' and the 'cambium of dead maple'. Smith (1950) collected puparia of Clusia flava in a dry beech stump one inch from the surface in early April (emerged towards the end of the month).

Clusia czernyi and C. lateralis are found in northeast North America and C. occidentalis is found along the west coast from British Columbia to California. Clusia tigrina and C. flava are known from Europe, but C. flava is also known from Japan and likely occurs throughout the Palaearctic. Clusia sexlineata is found in Burma and the remaining species are known only from Japan (Sueyoshi, 2006).

Clusia lateralis (Walker) on dead wood. Northeastern North America. © Steve Marshall

The synapomorphies currently used to define Clusia are as follows: one pair of interfrontal bristles; two pairs of stout lateral scutellar bristles that greatly exceed the apex of the scutellum (one pair sometimes lost); arista pubescent to short-plumose (not long-plumose); cross-vein dm-cu surrounded by wide infuscation (secondarily lost in several species); scutellum with central yellow stripe (sometimes expanded to include entire scutellum); epiphallus heavily sclerotized and produced anteriorly. Putative female genitalic characters include: ventral receptacle cylindrical; spermatheca dark (usually with dark reticulated pattern) excluding a small circular region around the point of attachment to the spermathecal duct.

Male genitalia, head chaetotaxy, and female genitalia of Clusia czernyi. © Owen Lonsdale

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 1
Specimens with Barcodes: 1
Species With Barcodes: 1

Clusia

Trees or erect shrubs, usually stranglers or less frequently scandent, dioecious, with abundant yellowish or cream-colored latex. Leaves opposite, usually petiolate; blades simple, thick, coriaceous. Flowers unisexual, actinomorphic, solitary or in terminal cymes. Calyx of 4-6 sepals; corolla of 4-9 free petals; stamens numerous, fertile in the staminate flowers, sterile (staminodia) in the pistillate flowers, the filaments usually united at the base; ovary superior, with 4-12 carpels, the ovules numerous, with axile placentation, the stigma peltate. Fruit a fleshy capsule, valvicidally dehiscent; seeds numerous, with a fleshy, reddish covering. A neotropical genus of about 150 species.