Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2f3bfbca093e2609cf450d800c0ac7dfd60e7e8b04a42c82c0205ee9c9756fcf' 
  AND token = 'CF9x0vEx/SCn66yzCr6aqO2m6sEmHQWIbBprZp3aa7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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