SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c181ee4d922028b5ee37f4787563409dd1033159b3a4ff154906bc172f8713f7' 
  AND token = 'x/0L5oBmKOKED9tV66/2Aqyp5VwgDaVZntjNEzooZ8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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