SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5eb070d6bb798e3973732109d61f12599bd18931e9c608442f661d1be041ab2f' 
  AND token = 'ztT1WtXze6T9I76HYeCTtLPoka4HA+B/pfLNHdNasDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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