SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70af1983d129d3f4f5816a782f8b12039f940882b6f6af34f33bdc038d03071b' 
  AND token = 'hruVUQeYpRKy8M6PiotvAg+f3D5JCqdg6+EXqb9zZ0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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