SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09b8c35de06fedc4ad6538154e66cf7a7f79b545d9f4682246e6b54da4b8bdfa' 
  AND token = 'pERRCLMSVzq8SeDTuIJHd/5Etuo971s5RIN61KYcibw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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