SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23885d079a4e6a35058c82e9fed2833e76d44431087fbd00b9ba267a944b3782' 
  AND token = '5HnHiraMQTNO7BNNm/Dq+VuHPScrvOVzkFLsU2BkhGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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