SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e140d4b6f466693f053cc23ac2f66ee66ebbbb8a48baac1ed4a2987ccaf24a79' 
  AND token = 'xaJYWtBOAljRNctdIEjVTmTEb1MC6lLmAie874Qnd1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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