SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '491fa1d722e7e59c62e2f685d75983e1e9a492a9be5898dcfad7bd90bd107d7f' 
  AND token = 'jJaSJR/9/3fXTBsw1VG4DsqSMqYHCq/es3LLjKZDoYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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