SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65ddf009a6bb136e9a7cd2a7f59ced2a6ed09c63f2da64408cfdb9a13798bbc1' 
  AND token = '36HxKJG79r2DuXMdHtYDVb+sUrk/yiQKZ8YUZZU5LvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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