SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bc94b5962cf5043a18823161e372529b983bd31f0cccd051b347526c68cf5ae' 
  AND token = 'ZTyjO2996lhpmG5kmmsUd1/w2oGdg8nshmB+W01mZhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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