SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c6b165ad2967bec28650c865195b092cb5461e8f6b824d85df4f1a468273e7d' 
  AND token = 'qrWQM7H/33+4XejVGl1WtGypMuVXnQmB8BEvmmJFSes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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