SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ebf38ce5d55dc77625bcd77cc37ea699aba2ae9ea5055c74540e720b7d47065' 
  AND token = 'mPv3u2QST4qrYUmkiRKbD4ihfrRImLYMZsAoNyf9spE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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