SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3666481dad79d51878130de02cb8dcfce6063097c33c0db6b559c8b1b65a146c' 
  AND token = 'i537wF9zDPmSkaR2VznbKTaqEBLbtTwsP/7miMne4gs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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