SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6aab2ef45fabb219af7de61956cb4f64177a071a3b021f60413532785a7bfafe' 
  AND token = 'YoCNHc6KfX/KDnL8nLibB7bUPIs3TM/qBt+JEiq7cPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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