SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d37aa485ee354339d8bbca473d8658b38360df4c65dc44f108dabc2240e627b' 
  AND token = 'VzyYN1WGy9S+PTJwBYcQ7NUKWH7gpa9QgZRl8XLxGQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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