SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac99e7d32b50fd780f30015f74ec794d79671371d6493132d397f4dcc5894855' 
  AND token = 'Ur6CLDVOxcC/BCr4faQ10ERbqixMgWQ84KObuesg09I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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