SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01be823e695383726940aba4fe01917807073ad81b5b15ec59f7b2558783fdc2' 
  AND token = 'ndC/qvsA4DoPvdRFZYwKa1vtGakh7hTiHNHNRgRUUng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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