SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32ffff32a259b90fc2230fbcdc2b45806bebcf52d4abd77fdf235755ce8a23b3' 
  AND token = 'KvMzdqcHPUuuLG6j2Agg+K4xqJvuglxIw2w1tQs+KQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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