SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fd432725f85ad5b0b6f7bbab5af8c018f88a9f60d190c4639d128e3442c4aaa7' 
  AND token = 'B/YsrhpCAt1MSAD4u2pg4ULII6ad2KHEp+vG6o78XXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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