SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '004191e5a5017d12a8ddd4061a578e180dc858697500709e2a8cba906204fd8c' 
  AND token = 'HpuxQa6dYzhOfUbmW86Z1WIvizSkOcYHYpuaSqqNo70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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