SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69fb8a90309b4de97b5a5acb8dbbadf4148400bf427f085169c630373cfbb115' 
  AND token = 'OmnegYSJfRjZsOwAWokftTcoKoNLUiKAl9ZsSBtJYkA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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