SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbf6e698ba4b58b2dcd0591d2689c0f3f6bdcfe0f1f852f72c235d3e82dee848' 
  AND token = 'YNOBosSS+vFWEpBVAm8ayLYlEgFdxn60QfCoGdjoHa4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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