SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e4003d0d8b61cf3fb0b20e4f9144ab07d722145179bbe001ade63bbdd30c5fd' 
  AND token = 'T8mNAJCjbOAAc18SWyd8pGvXgRHfrkbM9jT+z8rxlac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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