SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '909802d94e13c2ab6c6dfcbdeb2606215233abc99f14a742742bdd6711c7b5af' 
  AND token = 'KP5dIT0zXjcXzcMlpg5/Om8CzxaTPC05wY3tl/chhfM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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