SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd429fdb59932e09094ecedaea3d336f320d61a88c5d6bdcc7596a199bbf65410' 
  AND token = 'fCeXQnI7tAzm4IPL6zvAxXYfNRKIFZrGZJvzwvwQ6jU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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