SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bbdf2f789cfe5b09e7067d8082d9fea3abe8fb7a4ebe1671696cc3b0b4b65c5' 
  AND token = 'fe1lzHWnThTovQJ9k4irDxizb2iyX/hImr/VYRZVdKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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