SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cd08c5c5f849a3692461efdcb49408f25020cfc6a75a72746302a9d28ae72c2' 
  AND token = 'LSHd70P13+zVzLPMAQaLlW5JXKyAlpEiPSye52v1LGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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