Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4f776e3ad881853d8d08de46d895a9051357914e104665415fd0bafee97a3131' 
  AND token = '5ZpFn0YZmtgjA3uJoEDZsKp810NgBN2YsKDPBR+1IPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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