SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b41a25128781910c28eb93b0201c47323977071c3b686e87b1c6ec4bef2596f' 
  AND token = 'L5o5UC2DKgOc5nYBtmEVSZ9TF3Bl974gbhZoPrbEW9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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