SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd2c84cfe27364adc6ec9154d0851df081e30bb97fa20df90ad394bf48d49051' 
  AND token = 'HILJqD7d6rxT+p4IycKDmQBLk1CY65ih538axirO7zA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

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