SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '238d35780fa34c04db64a382022351ead5acff76c9408c139f6bf13625a8328b' 
  AND token = 'eocX/1Ti9tPRnRGw/rkuNViZgJ4ynjdV+9DkPF0AMsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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