SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8645aef3a259cf5bfbab343d62961bbc28dfa4107bd130d4c84d4bfc37c4cf7a' 
  AND token = 'YFSd9NDjBOBIfRR0gwIqhGtxq6J3nxJv+GeR5fTtxB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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