SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f77b8b5b4dfc995f99f2fe71c509c65426586897560b3a849a261a226ce7626a' 
  AND token = 'Fvd5XsnKmFBqjJ4/E4+r4q7etUTb1Oik+QMGjFxxVsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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