SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c1386846e89af7c13745726f913390811c2cfdd0259381ddb692d88901ebfdb1' 
  AND token = 'PaMvFqCaS4liTZgs91yCixFSSPnlMf3iAvvLKE8d5BA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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