SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e82523cba4451201478e94af0825e9f9051d6a0a4b6a6151573eb5735a6e85d' 
  AND token = 'qsPvLkXOXJ5miv+ulOwxriVM/qCj7e7bEYh95ZvHYO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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