SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00cc4f6eb08c40d827efcab2edcc9b4c9fd02c03c9e032a310a7ea95e137b666' 
  AND token = '54EzvAUBs/O7h+PU+yo1Nhtz+71mIkudh2VoxH9o1Og=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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