SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bb06daabdec5ee057486530a3782691d3b5375ea845718a86ab609234e41812' 
  AND token = 'ZKxA8mpDDCfLznw4WjvdMDcvisQNjwBB9IwF1CodU/A=' 
  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"
    }
  }
}