Metarhizium majus

Metarhizium majus^[1] is the name given to a group of fungal isolates that are known to be virulent against Scarabaeidae, a family of beetles. Previously, this species has had variety status in Metarhizium anisopliae (var. majus) and its name is derived from characteristically very large spores (typically 2.5–4 μm x 10–14 μm long) for the genus Metarhizium. There has been considerable interest in developing isolates of this species into mycoinsecticides: especially against the coconut and oil palm beetle pest Oryctes in SE Asia, the Pacific region and Africa.

• 
  Metarhizium majus infected Oryctes rhinoceros larva with hyphal (whitish colour) and conidia sporulation/geminating (greenish colour) from its cuticle.
• 
  Stages of Oryctes rhinoceros larva infected with M. majus. From left to right, 1st column: Infection symptom with "black dotes" or necrotic spots on integument; 2nd: Mummified; Mycelium (whitish colour) grow on integument; 3rd: Conidia (greenish colour) grow on integument; 4th: Decomposed grubs.

Metarhizium majus
Remains of Oryctes rhinoceros adult infected with M. majus: Dipolog, Mindanao, Philippines (1977)
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Sordariomycetes
Order:	Hypocreales
Family:	Clavicipitaceae
Genus:	Metarhizium
Species:	M. majus
Binomial name
Metarhizium majus (J.R.Johnst.) J.F.Bisch., Rehner & Humber (2009)
Synonyms
Metarhizium anisopliae var. majus

It is an anamorph, a suggested teleomorph was Cordyceps brittlebankisoides.^[2]

Important isolates

• The epitype is isolate ARSEF 1914: derived from a dried US National Fungus Collection culture (BPI 878297)^[1].