SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fa6f20d2597be8bba2ac55500d89540d34eaea31e73303bc1f7b8b039a36d64' 
  AND token = 'hXwGP1Wrg6+HJOjOIh+DBhwbvcbukFYNL056eNcb6U4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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