SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6098b25fd288c0f69f057f1aed44bc5dfc7461c1aab0841e985ace5027f8b2af' 
  AND token = 'L0slP8kQAHtybneTSeZXusdLi+ZC0aGsV2urQIuHYM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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