SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8eb7f2b21737b44a233a35a3135f11b16f0128b87d9b8aa30b44cb68f536d5a4' 
  AND token = 'TYFVtBKwlbPWzV9bYQH3dgxh6r3DjA1stMZmavv/1IY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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