SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '137fb4ef5e58be954f53ea5136d54560f5aca47f378531f37fc1acea878dbcb7' 
  AND token = 'L45RvTGz7XhkjYrwIG/nwU2q04jwoHx2HsyDygXn+E8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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