SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdc977e10ecf83bca10da79f36356528c4f8d137047c973e365f6de756a1746f' 
  AND token = 'wM/5avgM7QUa2YxTvhbJh4LbS2L2UyKnx8XbK6x404M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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