SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cef03acaa822206ace754e40bd830dd31451bbf77dda3cc315d159fbeec7ee8c' 
  AND token = 'ejxYuuchLvx5PLSjHR/Ra53jA4xkN/FF7u2bxgAAndw=' 
  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