SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '29ffc36b427dcfec223fe74d8a6a687d3a15d8c859575641319df7a60d476d58' 
  AND token = 'HOCJgVpXInbuZ/SNhgv8mXeAjyfDqAq1oIBV2GaWf7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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