SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f9723a58924aac9de874c6de9eebf6f0328aa018b31058dbfdb0f94c9ed844b' 
  AND token = 'nc9l5Dqcg0wSRAtc0gadTKrwItTTPK5DkypN1hbVTrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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