SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7595c27fa2495ad4aac70ff44c58f8013ac0443de375e5acae5caa56ad66af97' 
  AND token = '3Opa1cQ9qXqi1THGRLzzWRTv/ji87+XpngIl1ORuaeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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