SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '35248bda21e7a0beee331b49a5a612ce287cedc37246a5e5c387a1e2888accce' 
  AND token = 'w4v3SCNXKfJqZwyeVjLaxls2/B5j5wqh6pzs9zd4AVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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