SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '219cbe83710219222c55d310fc23541bbdf4458182a50d78f71edd3a3bd3ba19' 
  AND token = '4J9k8RrhfiTDn7DOEjEjA+YgiuKeZzaGpJHYJ0fvBng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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