SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b22fd128d1131d005b585c5510210253adf0ba8be659c9ec745063d268138902' 
  AND token = 'Nx1Gvwht2hBwp0FGHgZuL6LZd3thnlpW7hrF5YiKiHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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