SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1e3bbdf69ed961dc0bc1eb52c37d38a167ea4f3b4a98b2fba3033914c3ec963' 
  AND token = 'IZVVLh/psRGB4+BvylI115gDhvFM4adMLFzu+Jc2QGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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