SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65ed73d338f6ee845751b53af589790bbc1ee3d503cb9b7ba91f770a59d0a656' 
  AND token = 'OjTTw4xBmrOEtx9G0C4xHk0+1/oRjWPNyNWfQKfLrbU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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