SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a9b21c390bc85aab3c9b76e8df17896829c70cc989b28c2fac978f0eef17998' 
  AND token = 'Deala29KVr3taDMFXv9iariK8I27n5whD3kWAJ9ab/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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