SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d876c0face2d8712211be5254df15c2f714f7a33bff8cb7be6714b0d620b216' 
  AND token = '0s85Mw4nNxzH9II4Rvjxf0HEZpwYWhgJGVDgJH4f/cw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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