SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bdf70843c7da8fa10db1d6fe954870407405632956161685bda85afd97c4bf15' 
  AND token = '5crC7IB1XTysvmNNf3XWXzZKJfAZpX82+VLywG/Fvls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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