SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a33008aeb4f2d935818428c250fd67881fa86fe093217f5785ac3696eba8898' 
  AND token = 'zO/nLcMF7Z0s5DXMLcqzA8jMOb61GhVKVtSfgIe+1j0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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