SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd931e919d55bc02d71b76515068e3cda8bba3261f61e1e1f1436f3a314445773' 
  AND token = 'TSufqUZM9qH/wuOoqlUFd0JhGQTgU+/tMGBOYIc3ews=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}