SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '308d08a22ee2416282b1e02bc6997ba0026095a5b942cbe94cd374e82f3ca1c6' 
  AND token = '3N638tCPjoirlpLLFYsoDUfZOfWuSLh2W9dJszFtiss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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