SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd57c4b2732d11a2726260b0e7ca9c66efb720c0690adf4f73f5c2fc110a2f8d3' 
  AND token = '8ADKFtyyQUg0hlhibCwJshx/Og+B6b/sv1fobO7GWB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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