SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a8a326eada31e0113dbb84a374b8b78ce67e6a6447c303f522062acb2f7634d' 
  AND token = 'lxNHTsiyKPt7HuqWesEiQukzD9XiSYvgS+m3Ovjl/ts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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