SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f31719e7cf53be5740c4bd1cf670c969bb651de085bdbba3770688eaa7933101' 
  AND token = 'FgxiNsr4yE30vCbHTCDZYazKho7RwLkyds8Vv/Hpa7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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