SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9634daa4dc456776581463ee3c593b5b0a3f76ae21430a3eaa67ad5814436973' 
  AND token = 'qoNqBLs/LcID6KvAk6Pv6pTiQ/Tm/I33DOMN34yuAOY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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