SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '9636852d3ed2d46b66d1c6974f31f98c018455724b4876d3564b36daad7153d5' 
  AND token = 'MbxZ6KU/9L83A+pG55H5yJV9IKOOs/u56m2a9YJ0T5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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