SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b2e2304e69d43c0a31f7326c17f36210769912baa27e4f3ecbe35adb1e0a151' 
  AND token = 'YEb3+xpgD6zK0V6C5y2wichM1/hvhw279L9lJ0pM4ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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