SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd3ba349b31b169f74f86c2355387442dc354891f278bfe2227c046db99116c2' 
  AND token = 'DGy4muPhbJV6v63IjfanydY3j3AVC4+LAgbibvTyljY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

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