SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28a22f889d584a444a687f41ab564be74570ac6efbb749c1ab1d540b34a9a45c' 
  AND token = 'dHKJhB2L0djTKRfyZWFHbIaV6hJdpGkd+xSGf79WdMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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