SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a71784d21e68eef75df08f4f8ab5e0d0e34e093caa054e161744231273b78232' 
  AND token = 'CeGgXfOBY2MqMpLS6ryMMgYXzCUuFq/FE2TSR2UOhm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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