SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30ceb14ea85416e89a2bc04795f83e982da00e550522aed3da3f903f567fd801' 
  AND token = 'qANLvEZeSfhutVHAI3Q8S8R4mdlOAKivUpZT0Y3TNMQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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