SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd42a02093a1369fa7924bb38758275297d83bbb56357017fffb3ccbc7114032' 
  AND token = '3/g0FJNRDBbvYTkAy8J6caMlysTMQE8DEwbY4qINu+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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