SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09ecd8896d9d643643d91141f12dfac8edd7408a25be9b55e918529ab0c37431' 
  AND token = 'wfaSos7Miy1oL5iAeBe0UdVCEiXDYDmvL1eLI/zjCDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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