SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b9ddd7658fe0f3b41b546ec5c315cb1100c7be1ea693a5b482da0a179c8c17fb' 
  AND token = 'xc7niZ1xKKCRPiqO+Cv/gkh+f5VErOX1/qfkDTfVVYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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