SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00389769db4c105dd382c3ccae02ac56c0cb224da8a534fa0a6d670c0881eebf' 
  AND token = 'w5L5Ai9j5HhYkdfd7uAIxQLUgKXaQX5FM38auTipQtc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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