SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c039b2ee55ff9244e7b5a92d5f545be2e94984734055c08b2b7d144346c01f5' 
  AND token = 'HiR+jOe4IUt1nwoRag5V7zfBqMazrIf6/LVgkul6cXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

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