SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2785f4d6e191038682b34d1d85468e9abde6b71725e75898aeeb165d31a3c6f0' 
  AND token = 'tamO7PpLqJVE86o9RAYPQeYaL3C1Lfu1wygZlUF/nIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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