SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f385c9134719cbe8383c888af0e99d1adc193169ab6b8347faf623fa617e9362' 
  AND token = '45XlnjEKWiB6BUvQEUmd9EAxb8X0911ha08D5ammEng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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