SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0809be0b3ff21554dd7afa60444965a7c7966e79dd2634490621495d979619a6' 
  AND token = '0JyHGJKTAFXgXJZ7s/2+r5EE+yVwm4vgd309kHAus7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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