SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abd975bd9c7584bb81003b6f87cd7279fb4a608733bd02865e7d927734a97ea1' 
  AND token = '2mK75cnw7AEAuUkNIRGer8IJnP7XnyPnl6ltQU6p09k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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