SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4119daec88f871dbf603acde288cc630dfac2a6c120fa6ec409e73668bfd6c61' 
  AND token = '3i/eY1CBoi+2VkuCGqE55zjq9qh/AXTLN2CxCcl00qI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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