SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f89cc9369235525f0a4f337394bc07445f88a33faacdb6eab1982e83e7ed4f46' 
  AND token = 'DpmRJeuEdqN7delpPPyjgbeakJGJa6ZoqHkVIBAIkzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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