SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9cc3e17742b909fdbf6038e716710209ac95c1b75d82a4becd9ec4b2534213d' 
  AND token = '/wJXw7/j54yadlvahr9Yfm+v9s/+LlsiTSIGUSqTzGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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