SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f10f34f5e2ae69c70ad6af5f2e6980b16723599428a5ed27fe9f672826bb8541' 
  AND token = '78JePgVzEGRJFnb0GD8wwXhsscbh/oCbYusY4iQdIqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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