SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7146caa22e59bc8054ea4e749c219e75e1048b844a5750ed7db6519b6652db15' 
  AND token = 'ZjQB4Ay8Quj9HbalMfMEeBKV876AAkZq5TRz+/OiTZI=' 
  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