SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e91e89ef967b4429758225044305aa604feae7e5eda7684f8727761cb9170c4b' 
  AND token = '6mFYcbW40e8CWPV/IWcIkf2iLr0uQBNmQR5TsPBJfXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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