SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59de14ce2478a51a10e132d50307fbdb510494103d346ad15d382845ed5b75bd' 
  AND token = 'mWVXeX66R0CLyykdMKjuLiuvQ2yL/Pt+EJEhv4gJrlQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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