SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14a3c38e5780f9f1b3008406e3fbecee9ab722f876704e60e6c12e45c67cc157' 
  AND token = 'amp86RzL9YsDl/+w2CeSGsSHsp1QVylnZCYvkmzAdUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

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