SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e4c9d90ca2efe191f4b8028049e8d565a63475b9cb391bc5ad4ea12e36867af' 
  AND token = 'OOtumaMH4spHy/RM9phCWKGfweFOjitahnqI5YboaJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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