SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd32702be3802bc2c1ce526c85a62c1d6795d16acab733e1806ce21791cfd812e' 
  AND token = 'Vfj3G6ZYfdlTKzwKzOv/SJ0syDFyxsJ1fTCmVq7oFig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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