SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '000d990bc5aa7ca896cd1881f21f81b2d809ed9ce761ecec9ee5d0a4ab63b43f' 
  AND token = 'j0sKUMaMGExtmQtJeHbDe3xwjqW7KgF3mofXhEJON/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}