SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a2180b4494009e1bbf5b2706100df3d1bc8d3832fb036a3748f047f1949409f' 
  AND token = 'G4CjH9eSkskYN4nzy+kFJcEEHg5+P7wRlY4bvkKcvxg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}