SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6139180da28ed4feef185a8a7ec7939c2ee28aa69179f72b27962446f2c3b24b' 
  AND token = 'iAYLanFYCt1HYknhSMU2mZRsT8TU3VcmD62A4ZZjrWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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