SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8fdc06fef03a1b310888688e000ba7c7d6e8a29a015378192f362fffb41799f2' 
  AND token = 'biqPYwF0VJ9BK0s6fllhCLBxrhuxAuM1JI/WY8UfUZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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