SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd1b07f72eb90a80561aa2c7ef92a603df4dd0f9a4ef8285afcc7f3147962d561' 
  AND token = 'X8oSP+k3WVC3oc92foyBzcPnNY9CY9VE9IV6Tw+z6oI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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