SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9e1e50c4fdff26b72c98b47e46895e4c59e636a5b5daa48376b0b7a0fc515f7a' 
  AND token = 'OX9pbY0pURoCYAUv0rLEZqezgCzZaA+k3LHC/z/y6UU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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