SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b07e45185da333fb014c2eced03585fcd7816dbc4752e050ee0b450113726c4' 
  AND token = 'zeKzVQ4WaP0SrzqhukInHJaY/gtyViJyZJBSwB2EfsY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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