SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f4444bff76d7289cc5b9efe371382c327204c2720889ff8c41183a1ac7f2a80' 
  AND token = 'P6DOYQrIWq0z8rkZv13P2qaiqiS1r9ezkZedrK6Q8ZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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