SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d6533bc11439f0052f187ab9bfc9e5d2fe6d3b79fbc88328549831b53f190e4' 
  AND token = 'eJrnQ+V/bAAlDC01Wh6SSguSx9GqqiYPlOjtJd5vjqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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