SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '890779975cc7ce2e2ee9c8ef3e87be5bf7ff7301429fddae078399444a603baf' 
  AND token = 'diG0F08yLrNDah83EjaS660S25YYs8b2xuLRbI3lo2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}