SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74a756be0999618b79ab96ab794241c0df0b831f25a6358b4c699d5f618e85ac' 
  AND token = 'KiUuXAX/YM3QJn8EtEJInjd9GQS9pj+3Ow29Ugv0DdE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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