SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f1f66144be222374acea14a75a98d984938af8f9c8c856c27099f3c174f06d7' 
  AND token = 'Ep5qUcfCD9shgN11nxa+a0rJTpWIlF9IfHZYwsCoadQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}