SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e04e06f8ce4819b67186c1d2b2696d0913abb65b64e108deb5f12261d262d9f' 
  AND token = 'XI7gVihyGUDQOOmO86vRBIIViQJTmGA4TiFL5YfoN/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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