SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e1861366e7ee424f79d0f62fa9f8dc16f39897dcdd06fb5737274bad85d5747' 
  AND token = 'yO859zcLVabkUoa+KlQZHUrcauRHYBkQpJtIEtZigzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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