SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '920d892ead2fcbb1afefcb5f1185fcfbae5e85201a445a162c26ab5fa8c8d996' 
  AND token = 'ghwmNuyTeYA6uiZkaGUZAAaAcOKfgODRyRExQSDh2BU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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