SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cb885c90e44185bb335367362cf52a1bd44b318acf20a0fb6e8e1383d3df3db' 
  AND token = 'yX7y2K9o2h3O3JSEPpUDGMKjpH2HOVcFgwpyprKyIoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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