SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28774601f891f56853fe971f94c5366e402075a55c2b3ec87972b9cd4157e434' 
  AND token = 'vfOWnXO6zUO6aszlnXdZe/7ToShTKVqskuxi5yNQlaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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