SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '192e87529f8c903da0eede6963b8dc6e41f68c4353da8e1ab55cbd81b8f2dd28' 
  AND token = 'Zi9GMSPKnFzNpCnFXu/MmLGdMhxTva88tYjvHgdDlXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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