SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1035443f608f4405f513b13e95820f5b3f34fcd3d7f956fc90f97fdcd9286807' 
  AND token = 'cjfYZlKz/zLCwUQMy5pc2gM0k9M/jSOT+QA2ezd3aQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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