SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64ef09f1e2404d8a274c385fec8ff83f0221adf87bf78853463a41e06a0f5105' 
  AND token = 'vrGLqY4BmonxWGU1iPGggEtXwOE3qhbFt7dXBWqcxeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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