SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '752dba3083ffb5491f7401434458520dc82e14bd3ba7de62e620e84aa912ba8d' 
  AND token = 'pEXqL4SyAqrzdhtHkx1MxYND8vmjQ1nB+TEnrCbEyxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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