SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f0aefcc383aa9a02231d3449e31d64b07bd3787d0bf474f61d59979cee466351' 
  AND token = 'iUgd0MZrxdl5g9zXnVL029o4BUGY0+hdcEh1mr/D0Uo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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