SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ffc24ab57221c5242a740d53652328dfecd5fb52d3bab6c287b0417002216c7' 
  AND token = '36FZdQMwII8f+A31ZDG2qoOKARA/ZSxVpXEfGIzpQuA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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