SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '285e3b7deae2ceaadf163d3f8ae53234ff8bc21f4abe3a57b356b5ea661d434a' 
  AND token = 'e3QaxonrEo+kcxWtZ4p+1x5QWNSTagvy4Gw4t8HzMTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

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