SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '798cf5ada0fdef2efddb83e0d0e0f04b7683ff30058633e55aa9e8a1e2f3c0f7' 
  AND token = 'znpRXyOJD44T32yjkeAYuvB0bncO+siOJI66YwQUdIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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