SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2859d6900d99dc7a64398984626dd7c6f93280cf9e03d697ee130e92854c6753' 
  AND token = '7LpXs4X8aLr3QHBGr+8tLhQmH4dVbyVlfI74ywbpO7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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