SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '013303048f368c9f40df026a542e16690e354c8672ff8c4b8024db6274bfe575' 
  AND token = 't6RZo6g+klKYKOSVYLFgAKBS+b9l6LMePjJCNQzmzM8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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