SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa20453e55f8627dc5fe87109962aed8453add7287bfbe01753bd6646151077f' 
  AND token = '3wqj5U5AXLKQ6wXAyIewJVyVkuy81yWN4IKurFvd5lg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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