SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc87e7b26bc881bbff4890909503695d23e965aca20848634b7761887dba0dec' 
  AND token = 'tAqhZmsjabDUlMmc0RGsO1sMj9bq3inPAIo8qXWv5/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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