SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19172f1ccdd38d59137c88f994d0a2b0562e169655de0489773d3632ee1c9d54' 
  AND token = 'vSJmdv61k4GFF419SfgUAP0MXKrikKKxrRIgBVHvXEo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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