SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c7235f2813f16b2ada3928cfe4436e0be2bdb6ea119b6d4ab698bf7233c4c65' 
  AND token = 'w9C4NjPnOpxhWdqRbupwVai+yITKtMrGZgEmPQDwfqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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