SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5a6a6ba28658695b80495bab85e4c3984ee76adc28e6bf88e1d2f0dcc1210f84' 
  AND token = 'Ykce46dYKZrB+0qzQKkKv3HGNDku4xPfiWbfYgwA73s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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