SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79849cd83dfb16af172fdce9fce741b7fc2c6e1089a3071a253defb4e5dcf2fb' 
  AND token = 'KobiiW+ZcPCwnkzkU7Mh/Dv+h/88GM5/1Z2GogZ8dvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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