SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2971ff031f719efb76152fcefa1ba62fd653a1108c935564b2b0e642f74e8ba' 
  AND token = '16nIb9QlMJU3+pNr2TDP7DHdWZ3upyRAvFpLcbXmSew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

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