SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b595e0ef31bb454f48c8163c18be0ce71e9c8fe5a00413e566a6e436dab919d' 
  AND token = 'xO5C7J7nLMt7iyeFna0KXHGQBtuIPeysVOZe0C3DpBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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