SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58dfe1d3c952db079b8320bf9c189b99c2b663fbb80e8cf04e9539e019ec9f9f' 
  AND token = 'qHUA7uKGIozpvOE5kt8+ffBC06jzz83bf4HG6TGyoYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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