SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e17c9d7d0396146936c2eefe86449f5d965b1bf60903d892aadd21efdd7f7bc' 
  AND token = 'mlTPVJNmKrFBO95Kvd/0pBNDXHDMP59LtYRwjyZSn7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

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