SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd3434b48e155a60f6882de782cd41415dc25594b81402d61bfc3ac008921612' 
  AND token = 'ZOAMPXWdTKjsH7XhdipUXyP5pQkocq2oNKPLM9pMr+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}