SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77b4e92d3678bfee6b83faa43364dc857a6b8277c9d20b9c829bac1fe6060285' 
  AND token = 'wRiLpVMyHEgJmg/COImkbiXhFKNKpKE7v4sbHbNLm5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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