SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd14002ce1701c85ce105a2062b3c623e46f97817b8cd54f0b83dd2dc3efe10fe' 
  AND token = 'k4eCt8g/peyQOjpwXeeFip2GlU/98iBt4kXTfwO8K08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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