SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3d78e31d02e00eb48fa1b06012517ed4cc9956d259d8b16162269f82ba84cd84' 
  AND token = 'TGwga3CMKc3V97TAKkDQtXmUuKYTiQqd+Sc/DsH/MLY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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