SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93b26d22cbbf2862f5f60f213e05ea2a4c98789f35c320e066715f4c3362953f' 
  AND token = 'g7QW7EpVm4YFYHgqMSHmgCTrVc+gghykcS4WceJh5+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}