SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69adcd6193889c17a0dfe3d4cd0942685c39603839c116783dd4b7edb0015eb6' 
  AND token = 'jjkltlT0j6F3V1kBw+xJy/WcR7y7iiHvR+kaIm//TdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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