SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36b655be63e8f6f33378186f79294754866da3f4017a4f7632c7c8e4c5f63fee' 
  AND token = 'MU88yEoBtZo5R6RYp0XwGP7cz72fzDzvIjVd7DiWJPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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