Spinarak
Spinarak is almost exactly the height of Murkrow.
POKÉMON · HEIGHT & WEIGHT
Murkrow is 50 cm (1 ft 8 in) tall and weighs 2.1 kg (4.6 lb).

Pokémon names and artwork © Nintendo, Creatures Inc. and GAME FREAK inc. Size It Up is an unofficial fan project and is not affiliated with or endorsed by them. Image source ↗
An average adult stands about 175 cm, so Murkrow is about 29% of the height of a grown-up.
Of the 127 Pokémon entries measured on this site, Murkrow ranks 101st by height.
Spinarak is almost exactly the height of Murkrow.
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Phanpy is almost exactly the height of Murkrow.
This page.
Cyndaquil is almost exactly the height of Murkrow.
Clauncher is almost exactly the height of Murkrow.
Chinchou is almost exactly the height of Murkrow.
See all 127 Pokémon sizes, smallest to largest
Numbers are easy to read and hard to picture. In Size It Up you drag a mystery object until it looks right next to a reference drawn at true scale, then the reveal shows how close you came. Murkrow turns up in the daily puzzle at random, and the Pokémon practice set deals five Pokémon at a time.
Measurements are the canon figures listed on the Pokémon Wiki (Fandom) page for Murkrow ↗. Where a character has several forms, the size above is for the form shown in the artwork.