SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24146c621610c78224767d8941f5b752e6573c94517517c43fd4c95f0a183570' 
  AND token = 'WJtQiQmnwuINeOtzhuBl4xUDoqNhHOT4lG73FzZsEOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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