SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c18946b091d8bdc93dba685e6cedbdfc42e59304bb38cf7f4bd85904218cc13e' 
  AND token = 'nC/La6m5HOoeJ23270oSdqCV+imjTJ/iRemMRi5K1LQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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