SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '60c6b57c310bc58350626ec7b32522e13d33dd3e3654975445918d1699b230d6' 
  AND token = 'NzFP4GbAFaOjWZteJvbMNf6xpGoGhRjD8F2DbZ0AAXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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