SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22b0992197e37875a91805f24cacbe2806ab40e98b413089cefe58ca4a55915b' 
  AND token = '1LkDU9ytInVhmYv3t0krwebOUpDW0pDknJIZPqJQ4Ds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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