SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '118c84de1d6ba8721f7cabfef4cc3164569de07620d5fe82ce30e9e794117bb4' 
  AND token = '5sDdEJEvrKuvY7HzETBsR2JcOLs5Zk6zvkGqCGe0BvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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