SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40416f5c3fb277b5167790b4267db42cb873eb50b97f0b48f8247f520dc621d0' 
  AND token = 'TgM3BTUMVERwxWYMggOEvwVyKkHZILW9OyYvntjlUYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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