SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3654b9b3497b231daf00c28995e4f358e89c3a41f18aaa79fc19101dab328ef' 
  AND token = 'kZs9rVRGgwqWqM2CTs7ow0bD5DyR1r2CnvEXoaaDXiI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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