SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bf3f89fb3e20d2107286043c1ddb2ef7b69d40b2f9874c96cce85d083539675' 
  AND token = 'BBwQTkZJWJUMo2xoRZAqdSTE2zGgCFONGEGU2eX934g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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