SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f6c17e1d4d7ea33f98e2d4e63de39dc347fde2f039195708ff3e9b3a73d5160' 
  AND token = 'f0D9YXfDPcdqKkOJ1LrBXs1ZjzdXV04q2spghVx+CPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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