Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '70db1ddd7996c740875b2fa37ab10e784b362926efcab63e0d64c3406017ff42' 
  AND token = 'cf3jKMqvTt2X1xtULiHMqDm/pOsFFIEeIyjPlrovB68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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