Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89bfec729535a719a7660df612c09aed7d55fc6b3bf2f1f45d9e13de13faa4a7' 
  AND token = 'g2dkrCdsAJKzzTnmUCLPdJDnDjBDDv6zX7k4ygwi4s4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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