SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3edb9cfc700cb92f57365d3494eb8431b06e8d658d7962c93a356137a34f0c95' 
  AND token = 'jxuj9IBj4l5nvJyMs++V8OkeC86YvkKeS27cKOt6COs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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