SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08dafad7acdfb56347c5f08fd3cf429f139d7a1b6731a348e2446fafcf17c026' 
  AND token = 'r2S2CKf5GipgbRTYF3mDlA/E3PH9hOLd3M/TllCBDjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

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