SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e2d03ec0f08528071996215c5e0925ff5af793dae8102283934f41ca5167ea8' 
  AND token = 'Oxw0za5dm0rCulzdqaCAaIKX3M/2PG33dxqkfFWd8/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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