SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0167d85bdbc7eedf393c6647f10306590149b8d4a3b726526ac91b5019dcbabb' 
  AND token = 'IWZd0yk8YgD+ZQvHujUDVNkuQ8rcQ70zMwoB88IDt+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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