SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67f46bd13e17077a41441686295b483c0fa6c2e2eb8cc7586cb68e2d436e75fd' 
  AND token = 'p6g4zHP8vwUU/YyzQeGLlKhQcNZiEA24YXKvJ8F/0W4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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