SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2286c6a083c22f462b21d255864ae10af8193edee796c428ce4bc587258226b6' 
  AND token = '3TTlij5Lbh9ha8W8dIzPjbyWKQd7bGSgisBG7fIjG5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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