SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70ad27f4c76301bda14215d816dcdd06c9b963470cbbed1f8eb7ad16e4bbe77b' 
  AND token = 'AhPvLWQbMPK0/5gc5LjjN3UEXPmthV+SxAcs4/9Ql/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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