SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d8315f9579a30718481050915e4c5e7f61fd3b00cef336650d44ac23087b4f7' 
  AND token = 'XnKBdhXXskAsnUyvhIQWKMAH+5/fMJLsXQSg6ixDSZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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