SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cacb4aae496e6f6ab54dc47d84c5846c766eb4551429a220e9c57594362ed317' 
  AND token = 'cxRE/fhyBSofQJm5ReIkYhwr5L/MJF2+zY4lWRsX4Ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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