SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1277319b4c0fb5ea1adcbae64b60b83d5f12ab827f47e6536237021a33c88ed5' 
  AND token = 'MyD4zlRDuNvzedmlHJV2ZGmZVkdQVr1YexcDApsydPY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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