SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de4c2417e04de997b1c58c31628de1a53066512d292e0611cc1bd26dd2ab88ba' 
  AND token = 'bOJNDqxQGFL4/rdsj8B5LDvpttZzR3lyHdxaiD+uGSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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