SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e24515f58e2dc5590cb8b85aa2e140794a66701b6df6b4fc50604ba11941fd11' 
  AND token = 'OTObqT0yEX6aN5T239G3+RL1MJO3tIqT4axmu4VYxr0=' 
  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"
    }
  }
}