Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2115bdbf96abf1cd98561538e1dd22e2aa332f19699ac8ef1746ee172f5339ce' 
  AND token = 'Hf6nTx8hDtyGrglrNAbQAzm826HSWLyBIVhTP9UZZ2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE								Impossible WHERE noticed after reading const tables