SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd50188b30c3fc5d4e6abfef676d764f1044d5723382cf9f6c911734375e0487d' 
  AND token = 'T/FNwsQJ/QIVUnLLjuqmoKS/AZ94kK3o9aGAWplj5Zw=' 
  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