SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ce69ac717d90a3b595d8b024a1d4b61fb7c67af238ca94d272087f523bb5cfb' 
  AND token = '/D+ll4i3OytBwP+oZorNW+53VLRYtZvH6kw+i9krHMQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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