SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b966ffd5d7faf9fdc957771126453f89add074f5be95e70c32dc39cc25cf522' 
  AND token = 'vE/zCyxfThf1UvgVIFmnDM6KujXsr5Ms1TUur8g5ccE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

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