SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee646df216f4463c83424659570dcc58d4a88609bc70f307431e32558b69fdfd' 
  AND token = 'fDitwJnD/7OEd9BRH2QA5jH/5eEflgVtQYbbMpoqGCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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