SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f93fa5fa4f6f598e3006c2736d712d9aa816013b481128920016ce28e43e7e8' 
  AND token = 'G59tPP9NBCkLGUTPgymKZYR+5JFUuZ62OmUsSL+BDWE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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