SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d21d138f5fb2a6233b9718af8cd681e0f69f0ba8cebe7322b44de4e33d746d3' 
  AND token = 'fW+vTWvwdREwV2ZprPvkxHHFVHB/lQ06+m9XNyHjbRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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