SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dfcb389d94cb39fcf16e4a00152da20e5125c90d0dbcdf09ee6f34875b166476' 
  AND token = 'qvZ6kaNsEwJlOELWmndp+togUTjey8BhO4LjC02eMsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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