SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72be4d99626fc492818c86ab617b94eb5d6265dfd4c79b1d5f3f74c06868ea70' 
  AND token = 'FI/d+7H+HRC+dJ2sjY8zOK5YkY9GQsz0viY4omQHkKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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