SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '148515abace0e01abcac7364918031b9a198b8a950dc7a101ce74915d146d73f' 
  AND token = 'YeiyIBUjlyvTThO8yMmLmwPGiTxXqJAuWtNpnqegXYg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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