SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d2a91363c770efaeca3720b51c8a4b94bfa6a251a0c4516a7f8f6b00f9f7f23' 
  AND token = 'd92RSpVivnZKZOhUCHCzKaeZVUwvVG+C6eYBXcVDDgo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

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