SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '52a368533cd6de45e459b319d5ebad4a897e0afe1cf5c46155142579b62577ab' 
  AND token = 'abFYtF/GVj1GdwVlYUYCDUK+B6SRMUUGDCsKSyZ/Dk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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