SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f5f10fb643d0f495f69f896b50079626b999a6c5a58c47579972a4f6d5d18d2' 
  AND token = 'chbJgD7/LtTDX02p3G4dFjHwNBLDKNxCJqfU+zHTOiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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