SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '652e692dbe5ca765b30e977b0eede48889a92a0e836f868dadaab4184195aa27' 
  AND token = 'khe0ROBoWFpdY7ku/aLLtuCVjR83T65qysFTqH9axGc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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