SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce658a74ed367d382050b2bff14f6cc49a7938210a19b1de5c0402045ed62635' 
  AND token = 'NCS7KjxYwWELBtqiPV+lYDF0LaXC9jTNgW2Ahoous1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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