SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80d10bf8f5db99b831a333339733deeabcb7fdca40e1730e131a233d2a8a2236' 
  AND token = 'DWGCtLPPvHKZywmDn6sDfBsuSOD+ISWd/CBkMGbVbTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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