SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b10e2ec1302fef2196f2b60fdcfc8e435eed0a89594d47f113fc1c2a89822546' 
  AND token = '9+ovvjrZU3dAVg7RGzJF5tT4Klw/M32L9Yh1tg++g18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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