Up North it's easy to distinguish between a lime and a lemon. A lime is a sweetish fruit tasting like lime Lifesavers and smelling like lime-scented aftershave. Lemons are oval, yellow, very sour fruits with a low, broad nipple at one end. Down here I never see the thing that gringos call lemons, but they call fruits not seen up North limones, or lemons, and they refer to as limas, or limes, things more acid-puckery than any gringo lemon.
Whatever the situation, here we're referring to a small, super-sour citrus fruit best known in the English-speaking world as the Key Lime, or sometimes Mexican Lime. It's Citrus aurantifolia, and that's one below, a bit smaller than what Northerners think of as a lime.
Though the Maya regard this species as their own, sometimes calling it Limón Criollo, or "Native Lemon," what we're calling Mexican Lime is native to Asia's Indo-Malayan region. It's thought to have been introduced into Europe by Crusaders from Palestine. It had been introduced there by Arabs who'd carried it from Asia. The Spanish introduced it into the New World, there being a report of it commonly growing in Haiti in 1520. It must have been brought to Mexico early during the Conquest.
So, the Maya have known the tree for nearly 500 years, during which time they well may have developed a distinctive Maya cultivar. Despite the Lime part of the name, the small, very acidy fruits don't taste or smell like a lime-flavored Lifesaver. It tastes like a super-sour gringo lemon. It makes wonderful lemonade, and its juice can remove spots from laundry.
At different times of the year the tree might break out in very fragrant, smallish flowers, as shown below:
Notice the branch's spines, the typical citrus "wings" on the leaves' petioles, as well as the close-together dots on the leaves' undersurfaces. Those dots, typical of citrus leaves, are glands filled with fragrant oils. If you hold such a leaf up against the sun you can see what's shown belowt:
You can see the same thing in other citrus leaves plus similar oil glands occur in several other plant groups as well, for example Eucalyptus and Allspice. Translucent dots such as those above are said to be "pellucid.