SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2911d2022007747d3d6e3e76be0c5434ba618badaacc35958ed9513fe58ad64a' 
  AND token = 'xBLK6SsEKms2OHLmwexv4AZhufKxUpfyZwszIMUfHrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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