SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97d9bbb845c502dfc4b676cc94742e355682b70245f1e0340b11fdccdb673506' 
  AND token = 'Wo6z7jot7ZhL70DZ2ixcs1iHpGE4HgmcCnJI7tCXJow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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