SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf9c2cbf3786b5b675f20b17ea366cdd0fef2871d93574da72a298266693f842' 
  AND token = 'QsGG3Pnh6vw19QbJT3waQ9GSTLTZYA+K0hs9B115gmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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