SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11b02ac1f858517eea7dd56342c324e8bcc77d3de711710c06fcc5572f2c2d13' 
  AND token = 'gJ2s96kT4v6BzwSFnJeGhGk55KDlLf6e6UjPFy0FUpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}