SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f3af6a352812b08418e978b7b97d6a53ebb608ce525113237a94d9cf9086cc68' 
  AND token = 'Uxx6Hu4HrOw1tAzFG+nUlMpKqQEC3Ttg73sHWjfn+t0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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