SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91cbcfbc2ebfccd918c6f7a5a3a51aa4887cf55422614ed8b96c4dbfa511a182' 
  AND token = 'G8scO//w4A998sJV0upG4TtX230uczE6QvBDzhiip3A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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