SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40bfea12e388cfd15c7cce00c5be876e2e5482e52bbf29b31ac7fb0581458721' 
  AND token = 'B++ea+ZAWIUKQmv+iIeh+zCbhSNYA67eVQuIKGSnPyo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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