SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '218c69a4fcfa699e5b52f3fe2ecacf44a69ea9440a1f617f816422d823aa613f' 
  AND token = 'fhqjHWRoGcF20cE/Q5+OYbxA7W3TuxxNZLr11QhzMSo=' 
  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"
    }
  }
}