SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '09475e967dede15be5830803feafa8e2fccfc23f1cfe7b1db1b176711b602055' 
  AND token = 'v7hv2cOMkimZz2iVhj8y5F1h3iOpoNTUIU5XZNjatQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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