SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1b74005572043851c65d5b7c7a2ee250e6fbbb046e032da8c9f58f6a6680534' 
  AND token = 'qgDYmjfA86JFK2HRrb67xgS+gAmqqanEWK4XGAPraPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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