SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcf07f9d694b593ae237f8ec89471569aa1b6a16ceb52dc09a7ad59be2471b86' 
  AND token = 'IaIUsGR+0CdMlrNLFE+YeyTfyMNImdr3n+fEj9akYSM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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