Arcanobacterium

Arcanobacterium gram stain

Gram positive, predominantly slender rod-shaped, arranged at an angle to give V formation in first 18 hours. After that it becomes granular and segmented, resembling small, irregular cocci.

Arcanobacterium colony

(Source: Wikipedia Stefan Walkowski)

Beta-haemolytic colony.

Catalase variable.
CAMP test +ve.