SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e95c5d831929217707843ebf22cac485e4f56cf02d6e7a6b128a812940066e60' 
  AND token = 'bugztKCgPJtLBuhHjjxXMHtLmZpMSdGN0WjMA/Co59o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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