SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a4890bab04ccd120675ce5d1a632e2dcfb2c23ca388d4fd08f5397517b9408c' 
  AND token = 'azqmFWDg2hTQn7E/fXJuBGkM8yZH6MyIqmB/UC3FHng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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