SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a425e96b6d3ce5890e43fd382c44d20d9a74f25ca5874734ca04f3dd2b96293' 
  AND token = 'X7rUCiQIghKXADqbpZT7cnDV0U7q04nW2KfgVbhDBHM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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