SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb9342ae8644dd383bb4061402818ba10771c67cd2c3fda99f926d1ba098f47a' 
  AND token = '20kTrBKKAhIM8RUDVz3J0ABHH21zsIQcehJjzM6pokM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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