SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b026f7e01d8dcc6bfd857c0bdbddf18961613897bf813f3dde0c28e711ab5cde' 
  AND token = 'TbBM4ShD7pgbZoLiGLXwLEQYT2qSsd8th8uNmvzeYTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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