SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5869e12fafb0b6e2cbb295a612c03506a8a8e2928f272e1f6992fda1fa08c134' 
  AND token = 'G6A8Q/H4mB89M1oyX11KjGkUdEagBvt2zyChw7OB3KQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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