SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '122973e824e7203d1cc091e4a2e7f1302754aa9f9c24c637b18096c38acf506d' 
  AND token = 'VJzRb5KIFRuGBG3FnpOO4gLlMMScSseIAgPX+QlY9VA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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