SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e8f57419a315aa0e4f3bed81c816307c56f1dadc9f5bdfb24e273b8f2d1e05fa' 
  AND token = 'U/1aDzADbmhB1gVbHRbFIhqvTGY02Fo4hVRwmRR7NPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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