SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ecd50e88e5edeba3629a688c723f8d475619df0ec65dab9b538ea8b166ca510' 
  AND token = 'U6p3SYYs6D2aZ/woo3drR+17RB0Hl5t198HiD2jTLZ0=' 
  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