SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3648713f1b6845f6ea2c882b298b18c03f442f3d5836dc0f4452612711866ca' 
  AND token = 'EtqUewaudZ97XlrdjQZGIAfq3PcXjHQmj0EA5WBlv6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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