SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f7e5769f58b1db7a1471ab9701292ccaf8c2ecf104d759d483aab28d5093f10' 
  AND token = 'mj7Fh5v3C9qzla1i5wHKXU6e8yBI4ZweE/mbfzgRL8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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