SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed8cfbfd374e5affad83d46344e26fcc5b45eee36bc1ecd9b784b90d38eff045' 
  AND token = 'IYsHk7OiZjP3m1QOgy1jb0bqzumwsKgei5Fah7RYmco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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