SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87976157fec481b1cb5eb91806e326e35cff0c74ee390fe38a6ff67618de0574' 
  AND token = 'wHnybY5KcHaqTpObZ++UNLmMsnfNxP6Fya5puzEyDXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

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