SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15a8cd9ab77ed429485560b8fbcdebc8793fc30676a5428154bd4a0cf593eb64' 
  AND token = 'PaGZ/Maz7bvI8mMRYHAmwGT4BjPIOWATx6fqxiqx8LY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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