SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '245e3122765e7f49d2ef97b67af427aed1b4a7813ff5c92782d5a3a86874d7f6' 
  AND token = 'NRDUmF3H1hzqZBLdr4bzLMHgHm+8tDVFWg0erj5BYQc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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