SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99b04977e73e9accaa5eb457729aaf23595470c9369cd2bc55f2fb587812778d' 
  AND token = 'NZpVUXvCHgN5vq/SkwnKgIIRUViUkbO6ubi0qTJZfuo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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