SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f9bb6586cbc3e35b3e35f0ab958c24c90d0fab3d79d2458a73d740265b353d8c' 
  AND token = 'kjo5R3J4d3v5CJ510U8Za3YCdOrPlDxCsM0lE09Uls0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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