SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '68b43b81ec0b69b6fb3ce5f8a58593659fa9684730a7084bd79cb51cd72b7882' 
  AND token = 'yjWMnhdt/TqwcrJMqV2ij8Fm/JJ9gKnuowLDmzDDDaw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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