Type genus: Lichnia Erichson, 1835.
Characteristics.
Length (from the anterior margin of the prothorax to the apex of the pygidium)
4.0–8.0 mm. Body surface densely setose. Head strongly deflexed.
Maxillae with greatly elongate, setose galea. Elytra short, exposing pygidium.
Males with elongate, inner, distal spine on each metatibia. Larvae unknown.
Classification Status.
The Lichniini were erroneously classified in the family Glaphyridae from their
first mention by Dejean (1833) until they were reclassified in the subfamily
Melolonthinae (Hawkins 2006). Ancestors of Lichniini and Glaphyridae convergently
evolved adaptations for flower feeding and pollination, hence both groups are
similar in size and general appearance and are strong, active, diurnal fliers
that visit flowers and mimic bees. However, molecular phylogenetics hypotheses
based on 18s and 28s rDNA strongly support the placement of the Chilean Lichniini
within the phytophagous scarab clade among Melolonthinae lineages (Smith et
al. 2006).
Composition.
Arctodium Burmeister, 1844
Arctodium
discolor (Erichson, 1835)
Arctodium
mahdii Hawkins, 2006
Arctodium
planum (Blanchard, 1850)
Arctodium
vulpinum (Erichson, 1835)
Lichnia Erichson, 1835
Lichnia
gallardoi Gutiérrez, 1943
Lichnia
limbata Erichson, 1835
Distribution.
Species occur in Central Chile from Region IV (Coquimbo) to Region IX (La Araucania).
The distribution of Lichniini is localized due to barriers to dispersal
on all sides of central Chile: the Atacama Desert to the north, the Pacific
Ocean to the west, the Andes Mountains to the east, and a glacial climate
to the south.
Phenology: September to February
Natural
History.
Species of Lichniini are well-adapted for flower feeding and pollination. All
species of
Lichniini are almost entirely covered with setae on all parts of the body that
aid in transfer
of pollen. Species of Lichniini appear to be generalist pollinators, and none
are reported as agricultural or horticultural pests. The setose, elongated
galeae (or outer lobes of the maxillae) are also characteristic of all species
of Lichniini. The galeae are particularly elongated in the genus Lichnia,
reaching 1/3 to 3/4 the body length of the insect. These long, thin galeae
are easily inserted deep into flowers, and the setae that run along the shaft
of the galea trap pollen and/or nectar. When at rest the galeae are held extended
underneath the body. The labium has a groove that receives the galea, with
setae directed inwards that act like a brush to remove the pollen for consumption.
The larvae of Lichniini are unknown. However, adaptations for digging in adult females suggest that eggs are likely laid in the soil. The foretibiae of female Lichniini are expanded and fossorial, whereas those of males are slender and do not appear to have adaptations for digging. This sexually dimorphic character is particularly pronounced in the genus Lichnia.
Specimens of Lichniini are most easily collected with sweepnets on flowers or from peeling open partially closed flowers. No specimens of Lichniini are collected in association with any otherorganic materials other than flowers, and they are not attracted to lights.
Bibliography:
Dejean, P. F. M. A. 1833. Catalogue des Coléoptères
de la Collection de M. le Compte Dejean, Fascicles 1–2. Méquignon-Marvis,
Paris, 176 pp.
Hawkins, S. J. 2006. Revision of the Chilean tribe Lichniini Burmeister, 1844 (Coleoptera: Scarabaeidae: Melolonthinae). Zootaxa 1266: 1-63.
Smith, A. B. T., Hawks, D. C. and J. M. Heraty. 2006. An overview of the classification and evolution of the major scarab beetle clades (Coleoptera: Scarabaeoidea) based on preliminary molecular analyses. Coleopterists Bulletin 60(5): 35-46.