SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2f940208268ff235103368e7dc2ef61b885046404a5ae29eab9f6dd062975e5' 
  AND token = 'GD9IwSO5/1gcf6kpJ9EsknCOx0fIqXaOTvNuQ/d0Ty0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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