SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be14518841f1fea85ee12309c85de5878ed3148f7bbb682a9a1e565b09422bc4' 
  AND token = '9jdIOIWEmu3TzdqkLDVxIW2VvKV11B6uBcFzsKlMOsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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