SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '267ec8784589f3fc7c18bdd333a4f2412bd6c893fb861030b77332abf0fbcb33' 
  AND token = 'aSyXIjtw7xx8eKKAXxGAVNPi7BkfYmfbUd32+p/YEIk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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