SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '901f09e62df2bee27b9fff813ee3733bc04f687a4b6388c2485851be50bd0e92' 
  AND token = '1YxzmmjVwl5MjGs/yIt3CQIZrkR66EG5snSqpzZLQVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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