SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2e83e2639b1837c5eac34ea05bb1e7b27149249dd942d6112cf56dfb35a6dbc2' 
  AND token = 'ZRxTTWgIf/vsNB47UU9TiXpMOpGnjF7VzRYkjuRWWJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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