SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7d4244110952773475de912d48029ae6f8b70dbcf20cd541502186a55461441c' 
  AND token = 'vD2kDw1ZNbng4B+sYuxYGcf2TfmI3RwTV1tmGeguXRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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