SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af1a688788a10f3cc3f500761428163de5faa9f1388af2a4a7ddc6293900581a' 
  AND token = '/SWohF3saqUb9yCWq0CuUC7vrZ3FCYlLGjJAcj+QJlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

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