SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e73234672f5f02dbd1cd92b24926b517a765c7b48f4e02fa9191883f261ea5a1' 
  AND token = 'ziNNijf/03jpn//YBcSeVsFmcK1VXbPhvSIPWcqkekM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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