SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3009b9cf3cd16bbd613378ba67da72eeda9790ef5c32f9c24264f6797e63f246' 
  AND token = '6BE4qzqYU5pidKDs8m6XUph3H55RFd9fZEFvlGw/IFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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