Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8542da3b4f3a295385b23af6c8590f0735db5151ec1cbde5487912f85469c0ed' 
  AND token = '2q245QPyUPgLdxW2Ipzg8wiYMyPcz60SOE0AjC8yv48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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