SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb33da1d92e6214172866f4bd713311979c3d38878ead9468a1d4e2640ff489d' 
  AND token = 'K9RyEbft0ig5ntf3PP2H2R7DZb2P//aAJDDtJM/Wxw0=' 
  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"
    }
  }
}