SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2af28ea0ce722dbb3e40114bbf81ea664d9ee2515c8be466078dd0de28722139' 
  AND token = 'dOqQHO6I+MQQbY0u6s8RGSVKIAMyaVUwuBV/dl+c6nU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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