SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d2dabafebeeaf12a7179ede23317b50bae5d4dca9ffeea5ddb2e6077c635dc5' 
  AND token = 'zms+xHl37arainJlR3gorN6WfYrgUC3iGiLLbI0HJcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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