SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '328949a67c29a8960b0f0a3b9a0f573d0704be6ae11979b09843b44a5476509a' 
  AND token = 'onZWek4pnXDuvWJ2kqtykiPjfmwhBUk1NsU5VlHqjvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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