SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cce952b2cd42a80b8cd14fc28af7acb74f52de2aa009633f70dca4e6e3ed3013' 
  AND token = 'gV+aQqSxl2qKBRcYSMaAXaChXizSY2CADUJpxx9RVJ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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