SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ed111c8ed5d6d896a8d61158465289bba1bac5059d041e1044775937763ce3e' 
  AND token = 'U0l5cgG2MIFIYRIwu+7XeLhP7A27KVsj/QvJM8UmKMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}