SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '43f37c5cd817766bca4cfe066e937f665227bf1d3a6e56c8996b9872ff440f69' 
  AND token = 'glWKVu7OjzcheuJihzl0WR3ZOd3wzU1qG7CuLzVwpYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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