SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07b912d7117304a996607396d194ef51491ee576654890d6a4fbd27aa9148f7a' 
  AND token = 'ah0yBIaTCBpmjtFRGvrmkUkt7UWybUP+8z0A6cVCEb4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}