SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e1cac185753607cfc0f9d3aeef9335e229ac2f5e7736a00bd5466797a305f5a' 
  AND token = 'ojdUD4n3YmVKndDFYXPiIc55tPrBW7Xv2icO5YMiVXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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