SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25cdbb9788f23a8600b948b351f180b60cff706ebb86f8de6f4e322ac42e34ea' 
  AND token = 'sHxMQdM1QVjqQWMroq5hAH/wpMl8Mv3KKUXbBxSiqUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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