SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c37785c0995f07c4436e5cec8b8b919cf23d5c51ee984828e3ac008d93e11e57' 
  AND token = 'MXC27AuLCD6IO5ZoRxHb1WFsKx61jA1C6ckecvVFQfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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