SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe98ced5e291d5229f9ed1b5b488c973ab9d51b897ee3fd22ac02440ab5399b5' 
  AND token = 'VhrXmCYEw0PA++DvZtGunCQhLOxw6XxNTgeoMuQzzis=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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