SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc04fc2706615377afa6e164159161e3d9175074948aaf3bafe3f94b261caa19' 
  AND token = 'HHOg60JbdDYqBK7m44rasmoVqOddUAePtptnw3X0tXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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