SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79365502081d958dcc5556cbaf973f33aa4722d0b62bbdefdedbef8a7e584854' 
  AND token = 'nluJMe5LCWyTs743xoBXWx5tLTTiQ+W43yLOdVKXSvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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