SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '939fd5814247ab7764bd292cc616f0a1545ea5a58ad8223766125647ea4aa517' 
  AND token = 'fzs+E2lU9VZegGx5B0VgvSkcFLuUrWpwl7rp4P+8yII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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