SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07abdfd23abf3450d0241dc2e7f4dd4de413034638a0268ffdd4fbac346982b3' 
  AND token = 'Hqwnoufd5xBHH3Km4jNb0DRoKZ89Z8OhQ4KiVsDXlzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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